The recordings I made from the bug in fairly ideal circumstances in my lab and garden after SIX HOURS of setup are at ruclips.net/video/GyryQltyDwA/видео.html For those who have asked, Pierre de Fermat wrote a note about having a wonderful proof of a thing, but the margin of the book he was defacing didn't have enough space. He wrote it in the margin of his copy of Diophantus's "Arithmetica", perhaps in 1637. There's a reference to the margin note in the 1670 edition from Fermat's son saying: "Cubum autem in duos cubos, aut quadrato quadratum et generaliter nullam in infinitum ultra quadratum potestatem in duos eiusdem nominis fas est dividere cuius rei demonstrationem mirabilem sane detexi. Hanc marginis exiguitas non caperet." which my grasp of schoolboy Latin almost renders understandable. My esteemed friend Google Translate refuses to do it on my phone, but typing it in results in: "Now it is right to divide a cube into two cubes, or a quadratoquadra, and in general no power to infinity beyond the square into two of the same name, of which fact I discovered a wonderful demonstration of course. THE SMALLNESS OF THE MARGIN WOULD NOT TAKE IT" upload.wikimedia.org/wikipedia/commons/4/47/Diophantus-II-8-Fermat.jpg page 61, just under Quaestio 8 Also, I didn't go into how the demodulation works. I need to cover that in detail another time, but it goes a little something like this: If you have a diode in its square-law region, the current is proportion to the voltage squared. If you then drive it with a mixture of a pure tone at 1 GHz and the modulated signal, then feed the output into a resistor, the voltage across that resistor is the sum of the tone and signal, all squared. The tone is just B*cos(omega*t + phi) and the modulated signal resulting from a simple audio tone is the usual AM expression A*sin(omega t)+ 0.5Am(sin(2pi(fc+fm)t+theta + sin()2pi(fc-fm)t-theta) omega is just shorthand for 2pi*fc, fc is the 1 GHz carrier frequency and fm is the audio modulation frequency. A and B are just the amplitudes and m is the modulation index (0.05 or so) Now add the two together and square the result using the diode transfer function. You get an exciting mixture of results! After a load of trigonometric identities and wrangling, there are some components with sin(2pi*fc+phase angle) plus a load of other stuff. Run the combination through a diplexer to take anything higher than 3 kHz into a dump resistor and everything below 3 kHz but above 200 Hz into an audio amplifier, and you recover the original audio signal. If there is also some phase modulation, that results in multiple additional sidebands around the 1 GHz carrier, although at a low modulation index, the result is pretty much the same as AM. At higher modulation indices, the results are more complex, with Bessel functions of different orders causing a spread of sidebands rather like in FM. However, they are mostly removed by the low pass filter, except for the low frequency parts of the higher-order sidebands. The amount of phase mod is (luckily) quite low. I hope you can see why I rather glossed over THAT lot, but it would be fun to do a ten minute vid about it at some point, to exercise my MATLAB, Manim, MathCAD and storytelling skills!
It was beepin over the AM. Turned off it was beepin. Un plugged it was still beepin. I never could figure that out except like a hendershot tank circuit. What do you think? Im a schooled electrician and that scared me like a movin planchette on a ouija board
I have many different coloured shirts, there's probably some sort of coded message in the shirt I choose for each video. But I'll leave that up to the cryptographers to decipher
@@MachiningandMicrowaves I suspect the message is: The Soviet Union (bright red on your shirt) makes people see things as Black and White or at least gray. One Estonian writer called the Soviet Union the "Empire of the absurd".
I didn’t even know something like this was possible without active circuitry. A purely mechanical microphone with no on board power source that can “transmit” wirelessly is just mind blowing. The ingenuity is incredible
You can of course use reflections from central heating ducts, metal radiators and filing cabinets, but this was the first publicly-divulged case of a cavity resonator microphone
@@UNcommonSenseAUS Passive RFID tags use a slightly more subtle approach, using rectification like the later EASYCHAIR MkII devices but then using load-pull techniques in the near field rather than changing the resonance and re-radiating a back-scattered far-field. RFID tags are immersed in the reactive near field of an inductor driven by an exciting oscillator, where they can then change the loading on the oscillator. That is detected as changes in the amplitude and phase of the exciter, rather than collected by a separate receiver. The tag stores the rectified energy and activates a chip, which then changes the loading on the receive coil in the tag. As it is in the reactive near-field, the exciter "feels" a changing load. The changes are made very rapidly, so the data rate can be high, but very little power is required. Other tag types such as those used on toll roads use active transmitters to gain much larger range.
in clearance areas, your not allowed to bring radios or anything as if you talked even with a radio off could push sound agianst the speaker and transmit it electroniclly.... spy stuff is crazy....
His life story is pretty amazing, the lad met Lenin, knew Einstein and Charlie Chaplin, was (probably) into money-laundering to fund espionage ops in the Americas, appeared at Carnegie Hall, was thrown into a gulag, became a celebrity again and joined the communist party after the Berlin Wall came down "because Lenin asked me to". They don't make folks like that very regularly.
@@MachiningandMicrowaves Not to mention which banana you use. The yellow comes in a few varieties, and by me there is a purple one, the Natal wild Banana, which is totally different to the others, and also has seeds in it, unlike the yellow sports.
Luckily there is nowhere in the world that uses the Imperial system for anything other than pints of beer, and occasionally milk. (If you think the US does, then ask yourself: why would the US adopt a system of weights and measures proclaimed by George IV, son of the much-detested George III, in the 1820s, 50 years after the Declaration of Independence, and in the shadow of the war of 1812? If you said "they wouldn't", you're on the right track.)
Having chopped up a great many microwave ovens, I can definitely assert that resonant cavities are nothing but plain and simple black magic! This series is rather fascinating... my understanding is still only growing with the tiniest of baby steps. But your delivery is keeping me intrigued.
I love how you put your words together. I feel the same exact way you do but would never dream of being able to put it into words the way you have. I love it
What I believe, all the engineering regarding radiofrequency is taught backward, bot in schools and some Universities. They show a resonating cavity, a waveguide or a magnetron, and try to explain how they work by mentioning electric and magnetic fields plus some random formula. All the students feel confused, and sometimes inadequate. The only way to learn the "magic" of RF is first grab the math of fields, then the Maxwell equations, and learn how to write the right equation for the device you have, or want to design. It may take six months of learning in the worst case, but after designing the right magnetron, or the proper resonating cavity will be no more difficult than writing down your weekly shopping list. To learn correctly you cannot avoid following the right sequence; whoever propose an easy method, where you start from what is most interesting, will be wasting your time...
I dream of Gyrotrons. Gyroklystrons even. Those are beyond amazing, with a magnetron just to create a source of electrons. Tens of kilowatts of mmWave power, just from electron gyration in a magnetic field. Marvellous
Most of what is taught in universities is not very connected with the real business of devices. I was asked to act as an industry appraiser in the accreditation of a new Uni course in my professional area (cybersecurity). The course was ten years out of date and was designed to be easy to teach and assess, rather than giving the students a grounding in the real world. I was going to show the analytic solution for the capacitance of a small disk close to a large membrane, but it's furiously complex. All of the examples I recall doing when I studied electronics and physics were for ideal situations with lots of symmetries.
@@MachiningandMicrowaves I learned way, way more about the physics of RF devices and propagation from getting my ham radio license than I ever did in school. Much faster, too. Applied information is way easier to absorb and synthesize than abstract information. This device is pure genius. How fast we went from the discovery of radio to what is essentially a remote-modulated radio transmitter. Even the technicians operating the listening station had to have a strong grasp of the theory.
I passed my foundation ham exam today, but I was NOT ready for the intensity of science about to be dropped on me in this video. I feel thoroughly inadequate, but I shall keep endeavouring to understand everything after your introduction.
I doubt that more than a few percent of hams would follow it all, I'm working in such a tiny niche area of radio. I do more mainstream things as well, like using moonbounce and Auroral reflection on 2 metres, plus meteorscatter, but those are probably very niche areas to most hams. I also mess about on 136 and 472 kHz, red light comms and most bands from 1.3 GHz and up, plus 1.8 MHz QRP CW and digital modes. Working the USA from the UK with five watts or less on 1.8 MHz is a hugely enjoyable challenge. The glory of the hobby is that there is a vast amount of different fields of endeavour that you can play with, and a near-infinite amount of detail that you can investigate if you like that sort of thing, or just get one any use radio if you don't want to do deep dives. One of my friends decided to check the doppler shift on the QO100 geostationary satellite to monitor how it was saying on station out in the geo belt. I like using aircraft scatter to bounce my 10 GHz signals over the North Sea into mainland Europe. I think less than 0.1% of UK hams do this stuff that I find fascinating. They probably have similar niche interests that I know nothing about. The hobby has been fantastic for me since I made my first radio back on 1969
@@MachiningandMicrowaves I'm right with you, though the lower (super DC), leaves me wondering who you have to email to gain a contact. I'm 23 -3cms this way via QO100 too. All good fun. Tony G6YPK
I suspect the pressure equalising hole would have been even more important for atmospheric pressure changes that could otherwise cause a significant shift in resonant frequency, or even cause the diaphragm to push up against the centre pillar in the resonator and stop any modulation. In fact just getting the resonator assembled might be impossible without damaging the diaphragm from overpressure.
Excellent point. Although the threads are rather leaky, I suspect they would have used wax or something as a thread lock and that might have sealed the thing too well.
@@MachiningandMicrowaves On drilling such a hole using a tiny spade bit, I hand made a 0.3 mm drill (for use in brass) out of a wire "hair" from a stainless steel wire hand brush. It was surprisingly effective and easy to pull off with only the hand tools in my back shed and a magnifying glass.
@@lordchickenhawk Excellent! I've certainly made tiny spade drills from carbon steel wire, but only for plates 1-2 mm thick. Huge respect to the folks who did that 40x diameter hole
This is my first time watching one of your videos and the amount of references and jokes you manage to fit in while still being entertaining and informative is absolutely insane. Good job. You got a new subscription.
Thank you SO much for these eye-opening videos. I did not know of this until you brought it to my attention. I find the ingenuity behind such simple yet effective devices amazing.
There are SO many more of these amazing spying devices, I'm going to have a look at some of them later this year. None of this would have happened without Heather from the Radio Society of Great Britain, who put me in contact with the BBC TV team making the Secret Genius of Modern Life series. It's been an amazing journey of discovery
As I have some very slight knowledge of some of these topics, I slightly understood this. Fascinating. You deserve a lot of views for trying to explain something very technical with enough detail that the interested person with a bit of physics/electronics knowledge can follow it.
I get a lot of folks moaning that I use too many words, well they can go watch Shorts. I like words! It's been a fascinating journey through history and tech and science
I read about it in a book by Peter Wright a good 30 years ago. There was also a description of another high tech magic - locating Russian spies by identifying them by overloading the hetordinates in their receivers with the signal transmitted from counterintelligence cars from the street. If this overload created a dip in the frequency suspected to be spy transmission, agents had confirmation that someone in the building was listening to spy transmissions. It did not require any mechanical operations, however, it was purely electronic manipulation.
I rather cheekily call him Peter Wrong, but his ghost-writer did an excellent job with a difficult subject. Rather a lot of twaddle and bunkum in the book, but since then a HUGE amount of detail has emerged about all sorts of TSCM and technical ops. I'll certainly be making some videos about the ones involving machining and, er, microwaves. I might need to be a bit flexible about what constitutes "microwaves" if I can get hold of a working IBM Selectric typewriter to try making a GUNMAN project device and supporting infrastructure! next spy device on my list is an EASYCHAIR Mk 2 I think
Thank you ! While I knew the basic principles behind the great seal bug, seeing you construct one, brings it all together. Trig and waveforms , headaches of my youth. Only time in my life that the same problem was presented 3 times and I failed to solve it all three times, embarrassed I was but did answer the rest of the exam correctly. Sometimes a concept just fails to gel. Look forward to watching more of your videos. They tickle the dormant Grey cells , as ancient connections that laid unused, reconnect . Take care.
I understood exactly 0% of what you were talking about, but it's really interesting that you understand it. Lol. Hope you're having a fantastic Easter.
I've always wanted to deep dive the Great Seal Bug but never got around to it, thanks for the explainer! Also -- I think I see a familiar directional bridge on the shelf behind you!
"I have a wonderful mathematical proof for that, but this margin is too narrow to contain it" Ahh, yes, a quality reference sir. You are a man of taste.
Ahh man, ive really been enjoying these videos. you write them very well, and i love the little hints to other scientific quirks (like not fitting your proof in the margin, absolute gold!)
I am blown away. I have wondered how that bug worked for years. Speaking of years about 25 years ago I got an Associates degree in electronics technology. Had youtube existed back then and I had seen your video then I would have understood hat you were talking about. As it is now I got the basic brushstrokes of what was going on and found them fascinating. Liked and subscribed. Will be checking out your older vids and waiting for new ones.
I wish I had time to make more vids. Real Life keeps intruding. I have some more detailed testing of this Bug to film, then later this year I'll be looking at one or two of the other spying devices that used a slightly different method of operating, but still without any power supply needed. First though, I have a backlog of machining and testing of antenna feeds and all sorts of mechanical contrivances to get made for microwave filters and antennas and moonbounce systems
"weleda hat recht. der beitrag ist alles andere als objektiv. herr aust stellt das mittel nicht lege artis her. es muss zunächst stundenlang verrieben werden" Dr.. Aust macht das vollkommen richtig. Verrieben werden in der Homöopathie nur Substanzen, die weder in Wasser noch in Alkohol löslich sind. Kochsalz ist aber wasserlöslich.... "frau grams geht nie darauf ein, wieso die fürsorgliche mutter beim kranken kind mit dem falschen mittel keinen erfolg hat. " Die Krankheiten die Mütter bei Kindern homöopathisch "behandeln" sind üblicherweise Krankheiten die in den allermeisten Fällen von alleine heilen. Es gibt da einen natürlichen Krankheitsverlauf der meist so aussieht dass sich der Zustand des Kindes zunächst zunehmend verschlechtert und danach wieder zunehmend verbessert. Je nachdem in welcher Phase man mit der homöopathischen Behandlung beginnt verschlechtert sich der Zustand anfangs noch weiter (was Homöopathen dann als angeblich erwünschte "Anfangsverschlimmerung" bezeichnen oder sich alternativ damit herausreden, dass das falsche Mittel gewählt wurde) und sobald die Phase der Besserung erreicht ist reden sich Homöopathen ein, dass sie nun das "passende" Mittel gefunden hätten. Dabei haben die verabreichten Mittel den Krankheitsverlauf gar nicht beeinflußt. Das ist wie Regentänze aufzuführen damit es regnet. Regnet es nach dem Regentanz nicht dann war es eben der falsche/unpassende Regentanz. Und regnet es nach dem Regentanz dann hat der Regentanz natürlich gewirkt. Ist ja klar..... "außerdem fragen sich skeptiker nicht, wie die mittel ausgezeichnet wirken können, wenn dem tier das mittel heimlich gegeben wird, gar einem ganzen kuhstall. außerdem wirken die mittel auch bei pflanzen, patienten im koma und bei skeptikern" Und Homöopathiefans fragen sich nicht wie man mit Pflanzen, Tieren oder Patienten im Koma eigentlich das von Hahnemann zwingend vorgeschriebene ausführliche Anamnesegespräch führen soll um das "passende" Mittel zu bestimmen. Und wo bleibt den der viel genannte "ganzheitliche Ansatz" bei dem jeder ganz individuell für ihn passende homöopathische Mittel bekommt wenn man einen ganzen "Kuhstall" mit dem gleichen Mittel behandelt? ".- ob besagte gynäkologin nur einen schmalspur-kurs besucht hat, können wir nicht sagen. freilich ist eine gescheite diagnostik wesentlich." Eine gute Diagnostik ist natürlich wesentlich - nur findet die in der homöopathischen Lehre nicht statt. Die Homöopathie interessiert sich nicht für die Ursachen von Krankheiten - die "Therapie" erfolgt aussschließlich auf Basis von Symptomen und deren Begleitumstände. Wodurch diese Symptome verursacht wurden ist für die homöopathische Behandlung belanglos und Hahnemann hat sogar davor gewarnt seine Zeit damit zu verschwenden nach solchen Ursachen zu suchen - zu seiner Zeit durchaus verständlich da man viel zu wenig wußte um realistischerweise durch Ursachen der meisten Krankheiten überhaupt zu finden. "- eine berliner krankenkasse hatte angegeben, wieviel sie für homöopathie ausgibt. ca. 1%. also ein winziger bruchteil der kosten für allopathika. so was unterschlägt der beitrag natürlich, die "prophezeiung" der weleda bestätigend. :)" Die Gelder die für "fliegende Teppiche" ausgegeben werden sind auch geradezu winzig im Vergleich zu den Geldern die für Flugzeuge von Airbus oder Boeing ausgegeben werden. Ob das daran liegen könnte dass es mit den Flugfähigkeiten fliegender Teppiche nicht weit her ist?
The brilliance is in the simplicity of the device. It is so simple to not degrade for hundreds of years. It could still operate, had the Americans not been electronically vigilant. Maybe this type of device still operates in the embassies of, say, Nigeria ?
Yes a Gem of a video and I have just watched a few more... you may never know who is watching and appreciating your work. I sense your long hours in exploring and thinking through a project and of course the many midnight hours in the workshop... Time is precious but the eventual satisfaction of achieving is priceless... I did follow and very much enjoy your explanation of the physics involved. It is a shame to hear of your travel plans falling apart and that must be mega frustraing.... However, I wish you well, Thanks John Alex'
My teacher liked the term "condenser", or Kondensator. He mentioned it was the German name and was only replaced with "capacitance" and "capacitor", because Germany lost in the WW2. In fact, we still had two choices for our text book, which in my case ended up to be "Fields and Waves in Modern Radio" by Ramo and Whinnery (???). Some students picked the German language alternative. Then, in the final tests, there was a funny incidence. The professor had followed the Ramo & Whinnery book wave sketches, which we dutifully copied from the blackboard. This one smart student caused the professor to complain that while that student's result was O.K, there was something odd about his sketch. The student replied "Yes, sir Professor, you drew the blackboard presentation in American standard 3-D orientation. I used the European standard perspective". Evidently he was the only one in the group (including the professor) who had completely mastered the idea. I was lucky to be in his 3-student team in our lab exercises.
Some microphones work purely on the condenser principle, where the movement of a thin plate in response to sound alters the impedence of the microphone, as explained in video.
@@chrissmith2114 Theremin would have been well aware of developments in condenser microphones, although he left the US just before the cavity RF condenser microphone patent was published. Condenser mics using DC bias with a series high value resistor to give audio voltage out as a result of the charge between the plates averaging out as a constant number of coulombs, and when the membrane moves in, the capacitance to the backplate increases a tiny amount and as charge is capacitance times voltage, if the capacitance rises, the voltage falls. On average the capacitance and voltage stay constant over a second or so. The Bug design is pretty much a direct lift from the US patents that Termen spent much time reading. It's pretty certain that he was working for the NKVD while in the US. Fascinating story, there's an interesting take from some Russian authors, with a title like "Russia's Edison" that adds a lit to the story, although there are layers upon layers of disinformation
This level of technical elegance is oft overlooked in modern times and is absolutely necessary for the next stages in computing. Thank you for sharing this extremely interesting and scientifically _sound_ knowledge!
I absolutely love this series!! With all of the incredible intentional engineering and design it took to make The Thing work, it makes me wonder how many random metal doo-dads in my house are accidentally a perfect audio/RF resonator, such as the Coke can I set on top of my vintage Disney lunchbox, along with a few wood screws and penny. I’ll guess I’ll never know. 😅
jajaja...i was thinking something similar. and i dont think the emiter about this interesting video needs a power supply. just another metal with the same frecuenci in a electronic mesh.
Brilliant description! If you read Teslas papers, you will see his circuits were tuned to resonance, just like tuning forks. He actually shows how the ground works as the tines of the tuning fork!
About the 1ghz transmitter - there is a mechanical device called frequency multiplier. It is very bulky, but that allows to have a simple carrier like 125 Mhz that after a couple of multiplications gets to 1 GHz. On the other side you can have mechanical frequency dividers. That way you solve the electronics problem.
The shame is that we will probably never know the names of the scientists and engineers who came up with such a delightful creation. With my 40 years of experience I grasp the concepts but with the modeling tools we have today we could recreate or even slightly improve upon this design. At that time, in the Soviet Union, immediately after world war II it was pure genius and inspiration. Eventually the us vs. them aspects of scientific discovery falls away to only leave behind the truths of a theory turned in to a workable solution.
@@Tishers The progress in many countries during the 1930s was extraordinary but the unique circumstances of the sharaska system certainly seems to have developed her white heat of technological progress. However, if you compare that with what was happening in other countries at the time it's not particularly remarkable. The list of scientist and engineers in the sharaska system is known, but the specialist clockmakers watchmakers and machinists who did the work may never be identified. There were very fast developments during the middle 1950s with a whole range of similar types of eavesdropping system. I'm working on a replica of the EASYCHAIR Mk2, but right now I'm working on something from 1925 that shows an extraordinarily advanced set of technologies being harnessed, by an engineer who stood on the shoulders of Giants and pulled together threads from multiple disciplines to produce something quite novel.
@@I967 While it's well known that Lev Sergeyevich Termen was the brains behind the system, the question that Tisha raised was, I think, about those who did the machining work and electro plating and wood carving and all of the other associated trades involved in the project. While Lev was a skilled radio engineer, I have never read any references about him having watchmaking or precision machining skills. He was a highly practical engineer and there's a piece he wrote talking about seeing a lecture by Ioffe, one of his mentors, explaining the photoelectric effect without the usual mathematical formalisms. That really fired him up and put him on the path of invention, despite not being a hugely gifted maths or physics student. The names of those other specialists will, as Tisha says, probably never be known.
You need to visit museum of SVR (Russian intelligence agency), in it exist exposition about it with photos and people behind. Museum is pretty old (opened back in 1970s), in it incredible lot of interesting things/stories.
I just found this video in my feed and am blown away by the quality of the information and presentation. Immediate subscribe! Looking forward to watching your other videos, you deserve way more subscribers!
I feel hugely blessed to have ANY subscribers! I started this channel as a way to recover from the grief when my wife of 37 years died of cancer, and I was astounded when the first hundred subs arrived, then I put out a couple of videos that were sort-of OK and BOOOOM, it took off. This is only the third or fourth one where I've appeared on camera, so I'm still hopeless at being the "talent" as well as the camera op and sound engineer and coffee-brewer and editor and colourist and scriptwriter and researcher and roving reporter, not to mention electronic engineer, machinist, CAD operator, programmer, animator and Physics researcher. There's no time to sleep, but I'm having SO much fun. Just wish I could get on to a weekly cycle. Ideally I want to do a 24 minute vid every second week and a 10 minute one on the other weeks, publishing at a consistent time, but I have to fight my self-defeating ADD and crushing shyness all the time. I'm giving a lecture in the USA next weekend and haven't written it yet. No sleep for me tonight!
My mother says that all the time when she's talking to me. So do my Chihuahuas. Although they only understand important words like "walk" and "dinner" and "snacks"
Very interesting. To make sure I understand, it means that someone was nearby the ambassador's study to pick up the amplified signal by the bug. Thanks.
The receive station and recorders would be in a building over the street that was shielded from the transmitter building. Not sure of the details but I'd guess the transmitter was 140 metres away and the receiver a little closer. The operation would have been quite a team effort
I got the Fermat's Last Theorem reference and Blues Brothers reference. I'm sure there were others that I didn't catch, but I love that there was no explanation. If you get it, you get it. As a technical channel should be.
Maybe the metal was copper sheet and then silver electroplated to gradually bring up the thickness as well stiffen up the walls ? That way the precision was not a machined process but a gradual build up through electro plating ? Which would give you the ability to precisely achieve very accurate tolerances . Also create many that were slightly different sizes to experiment with getting them working properly.
@@vainwretch The analysis by the FBI and Navy Lab showed it was nickel foil with silver plating. Copper and silver make terrible diaphragms because they are too ductile and lack the stiffness of metals like nickel. There is a complicating factor though which is that the conductivity at around 1 GHz of a very thin diaphragm, especially one made of lossy nickel, is rather high. The thickness was quoted at about 6 µm. If that includes the silver plating, it would mean that the skin depth would be far less than required to get really good performance. Generally you need about six skin depths. With the current dropping to 37% every 2 µm, it takes about six skin or 12 µm to get to negligible current levels. I suspect that the measurements given were possibly deliberately misstated.
@@vainwretch I think you are possibly right about the body being electroplated as an additional measure to improve the quality and precision of the fits. It was made of copper with silver plating on top, and with silver being slightly self lubricating although not as good as gold, it would have made sense to the RF engineering side of Termen's mind to get the dual benefit of variable thicknesses of plating
it would've been relatively straightforward for them to have produced an electroformed nickel foil using a slowly rotating cylinder in an electrolytic bath. I have a 1 kg piece of titanium round bar that one day I will use to make a silver plated nickel foil using two separate electrolytic processes on the same material.
I was in the Navy and attended advanced first term avionics classes which go into advanced topics like RADAR and Microwaves. Klystrons, magnetrons, and waveguides were always kind of magical. They either worked or they didn't. It's not like we were going to troubleshoot the Klystron down to the component level if the unit is bad. We would, of course, determine if the unit really is bad or if one of the inputs were bad, but things like that are remove and replace. I worked AIMD and things like that pretty much immediately went to depot and probably eventually back to the manufacturer. We never saw them at the intermediate level. As far as RF is concerned, I have great respect for RF engineers and technicians. That stuff is just plain magic. I worked on SONAR gear and everything was in a nice low energy spectrum (audio), so I never had to deal with RF :D
@@MachiningandMicrowaves not rubbish at all youre definitely a crown jewel in the youtube community. I can not thank you enough for all the work you put in to these informational videos!
I'm thinking seriously about making a limited edition run with gold plating, in a presentation case, but maybe a watch-glass window in place of the membrane. Gift for the geek with everything
Brilliant video man!! I always wondered how they just about exactly did the trick and I had a pretty decent/correct idea of the principles, but the actual device was much more deceptively simple and elegant than I had thought.
@@MachiningandMicrowaves well you've really demystified it in one way, but in another I'm only left with a deeper sense of awe at the elegance and simplicity of the design. So much so that even a cursory direct viewing of the object itself (not the seal but the inner workings) is not even obvious enough to immediately raise clear suspicion to an untrained eye, like say your average embassy removalist or cleaner, it could be mistaken for some hanging or balance device related to the ostensible gift. I'm really intrigued by the writing on the back of the item, can you make it out? I remembered reading about this roughly 30 years ago in an old spy book when I was less than 10yo and being fascinated, remembering it very clearly ever since and so always happy to learn more whenever the subject came up. Your re-creation is impressive but so is the follow through, such as your animation of waves propagating down a street, really well done. I'm no radio whiz just your average RUclips viewer, but really impressed and appreciative of all your explanatory efforts. See, not having any expertise I had always imagined some passive device might have been like a little crystal radio set, I definitely expected perhaps a coil and a diode, never in my life would I have guessed something so arcane to the untrained eye, so while I admire your ingenuity in recreating it, what you've really successfully communicated is grounds for me to be impressed with the Russian originators, knowing all the practical, material and technological limitations the whole world faced at the time, let alone the Soviet union with shortages as they were, even (as you pointed out) limiting what was likely available for the two items of powered equipment between which the great seal formed the graceful nexus.
Oh sorry I see now it says "Property of division of security department of state" I was watching on a small screen-in-screen before I didn't realise it was easily legible.
Yes, they stuck that on the back cover. The original has gone missing and there are no available images of the main elements of interest around the bronze ring attachment of the membrane and the precise slot layout on top of the resonator
The suffering I go through with "documentation" written by surly coders who hate the job and do it terribly is just immense. I remember how well written the vast documentation store was that came with our big IBM systems. The thing I'm wrestling with at present runs mostly on Windows cloud servers, but was written by Linux techs whose idea of an example of usage of an obscure and poorly structured API function is to paste in a shell fragment, with the underlying surliness of a teenager aske to tidy their room but believe they are some sort of God-like Genius and think documentation is for simps. Yeah, those are what we call "Vulnerability Generators" in the cybersecurity world. Lovely. Documentation written by folks who can't write, don't want to write, and directed by management to spend as little time on it as possible. Great if you are looking for a way to sneak into a system. I think I am suffering from burnout and getting cynical in my dotage.
@@MachiningandMicrowaves Truly don't blame you. I'm one writer for an org of 250, so as you can imagine, most people are doing their own "documentation" and there is just no quality control. And if you survey developers on their #1 pain point of their job? "Crappy documentation" is what they say. How ironic!
Have any of you guys thought that he just explained Havanah Syndrome? They weren't using an EM Weapon on the people who were stricken with it, they were bugging them and they were collateral damage. The transmitter tube could have been something from us in the form of lend-lease gear too. Lastly, what are the chances that they would heterodyne down to a regenerative detector? They're known for having a wide receive bandwidth that would make any sort of dynamic fluctuation in frequency less apparent, although at the detriment of being more susceptible to noise which may not have mattered nearly enough back then.
Have a read of the wikipedia page about Havana Syndrome and the Moscow Signal. The signal levels for the Bug are tens of thousands of time lower than those we all get from nearby wifi and cellphones. The only harm from RF is thermal heating, and that needs field levels that are well above the ICNIRP 2020 limits. Those Havana Syndrome effects are usually dismissed as shared hysteria or effects from infrasound, ultrasound, chemical treatments for Zika, stress and so on. It's fascinating, but there's not much in the way of evidence. RF signals are trivially easy to detect, and at least in the 3 to 10 GHz range, a few watts on your hand feels pretty hot, despite there being no measurable rise in temperature. Reasonably High levels of pulsed microwaves are supposed to be able to elicit a response from human ears, see the paper by Allan H Frey, (Journal of Applied Physiology, Vol. 17, pages 689-692, 1962) journals.physiology.org/doi/abs/10.1152/jappl.1962.17.4.689 Frey reported needing about 275 mW per square cm to elicit an auditory response.. USSR safetly levels win the mid-70s were 0.01 mW/cm^2 and UK limits were 10 mW/cm^2, so that's a pretty significant signal level. The illuminating signal for the Bug was around 2 million times weaker than Frey's experiment. I think USSR scientists and manufacturing plants were entirely capable of making their own UHF tubes by 1943, but with a well-developed procurement network in the US, there are all sorts of possibilities as well as potential lend-lease sources and UK supplies. My stepfather worked on the Arctic supply convoys from the UK to Murmansk during WW2 and said there were lots of interesting-looking packing cases on some of the shipments. Also of course, there are potential supplies from Germany before 1941, but there was certainly a mature vacuum tube manufacturing base in various parts of the USSR in the 1930s. Can't see any reason to use something other than a homodyne approach, although a self-oscillating regen might get injection-locked to the exciting signal and give much the same effect. I haven't seen any direct evidence, just multiple anecdotes.
I have no understanding in the field, but it's amazing, a sophisticated tool for Russian espionage from 1945 is still an enigma and a creditor after 78 years.
The FBI, CIA, Naval Laboratory and British intelligence folks knew how it worked soon after they received the bug, but it remained shrouded in secrecy and misinformation until the 2017 freedom of information release of all of the papers. A lot of internet sources are based on earlier articles that suggest some highly theoretical operating modes. I would say to all of them, just make some units and try them. That gets rid of speculation, when you have a real device, you see for yourself how it behaves
@@jimmon89 Shamelessly stolen from VidIQ and several others with a Kallax. Then someone pointed out Alec's most splendid version with strong colours and overhead lighting instead of my pastel shades and rear curtain illumination. I got background envy. Also he has WAAAAY better hair!
Who? Communists? :D Do you understand what means communism? Simplify: it is when everything in property of everyone. Soviets rejected patent right (as result arrived funny situations, as example when US took Soviet movies and show to own people as it is US made movie, at the end of movie even show fake names of actors - it was legal because Soviets lived in copyleft ideology, you could without any restrictions to use any of they tech/product). Another example - when you bought any Soviet device, with it you always got full scheme how it is designed and works, because again - any work (e.g. some engineering design) immediately became public property. USSR had only two options: or make public, or classify as state secret. As example technology of stealth for jets came to US exactly in such way, fundamental work about it was openly published by Soviets.
Wouldn't a negative inductance be equivalent to reciprocal capacitance? I think the seldom-used term for that (when applied to a capacitor) is elastance.
Elastance is definitely the word. I asked Google and got spammed by this pathetically-useless answer from Quora's rubbish AI bot: SAGE: An AI bot writing "helpful" answers What is the inverse of inductance? The inverse of inductance is called "admittance", which is measured in siemens (S). It is a measure of the ease with which an alternating current can flow through a circuit. The reciprocal of inductance is called capacitance, which is measured in farads (F). Spoken with all the authority of an opinionated and cocksure teenager who once read an incorrect Wikipedia page and mis-remembered it. Great. Not "helpful", just completely and disastrously wrong. However, the humans on Quora are also mostly wrong, so it'll fit in just fine!
You managed to make this so convoluted and difficult an explanation that understanding what you're saying is harder than making one. Trust me, I've made several, and got two to work. Had I heard this first I'd never have tried.
@@matthewhopkins7042 great stuff can you publish a video of it working? It will be fascinating to see what results you managed to get and how you dealt with the details of the diaphragm and plating and what resident frequency you found? Looking forward to seeing it!
did you manage to find a way of silver plating the diaphragm? How did you manage to tension the diaphragm? Did you use the original method with a bronze ring with an internal thread? What sort of percentage modulation did you achieve? What sort of receiver did you use and what sort of electric field intensity did you find was required to get a good signal to noise ratio? What did you find the optimum links of the external antenna rod to be? Do you have a recording of the sound quality? Mine was very echoey and, resonant because of using that stretched copper diaphragm which was definitely less than optimal.
On your other point, I tried to be a scientifically rigourous as possible within the constraints of a relatively short video that wasn't an academic lecture. There are several other videos that talk about the mechanism of how the bug worked in a much more general way, so I am not going to apologise for attempting a fairly rigorous treatment. I'm not a professional presenter or lecturer or scientist. I'm just a hacker who makes interesting stuff in his shed!
@@matthewhopkins7042 Do you have any detail, recordings, photos, video or published results you are willing to share? I'm aware of two or three other makers who have created working models, it would be great to add to that body of knowledge with your results
Transmitter likely was actually US made, from Lend Lease, and the receiver was probably made that way as well, using cavity filters made from brass, who probably were chosen so they would roughly track the cavity temperature wise, so were probably kept in a nice heated room to mimic the office temperature. Tuning likely was very critical, and used multi element Yagi antennas aimed at the room in question, with probably a tiny feed to the receiver, making stability less critical, as they probably used another LO to mix with the received filtered signal, probably via a multistage cavity filter, to get the LO for the receiver. Stable LO at low frequency using a crystal oven was probably enough and low noise. Then mix, run through a few crystal filters, and you have a reasonably stable system, depending likely on US made acorn tubes for RADAR, stripped from imported equipment, and US made test gear to go with it. The high RF signal for excitation probably was close to a TV transmitter harmonic, deliberately transmitted to cover the bug signal, but far enough that they could tune it out with filters in the receive chain, hoping to have the US think it was just a spurious emission from a badly made transmitter.
They certainly used TV signals to make the later systems like GUNMAN, but I doubt that was part of this design, they were just banking on nobody noticing. With a homodyne reciever, any issues of stability or frequency changes are eliminated, although of course you have to re-phase everything if you change frequency much. With enough signal, direct conversion to AF works OK, although I found with a lot of tweaking that I could also get it to work with AM on my Russian Malahit SDR. It's not actually slope detection of course, as the TX frequency is constant, but the amplitude and phase change with modulation. I tried to pull out the phase mod in FM mode, but couldn't get it to detect anything. I think a homodyne with a baseband filter would pull out the first order Bessel function sidebands along with the simple multiplication product that makes DSB AM. One day I should make a larger unit with a more controllable diaphragm and proper anechoic chamber to see what actually comes out when it's fed with a coax probe
soviet union was developing magnetron devices in the late 1930s and would have had access to klystron tube tech post 1945, also had indigenous vacuum tube manufacture pre-war, so i dont see why they would need to go scavenge for bits since they were quite capable of producing anything they needed.
@@andrewbaluk1663 True, but if they could buy cheaper than make it would be done, plus also the knowledge that they were spying on the US, with US made equipment, as well.
I learned about this AMAZING STORY from the show "Dark Matter's Twisted but True" I loved that show. This story Facinated me and you covered it so in-depth. Really glad I found your channel.
I always assumed there was a diode, acting as a frequency doubler to the incoming signal, with that doubled frequency modulated with the mic, and then retransmitted. This is much more elegant, and I assume, more efficient?
@@MachiningandMicrowaves Yes, and a good demo of slope demodulation to recover an FM signal with basically an AM receiver. Horrid noise immunity, and very poor performance, but it can be very effective.
One thing I have always admired about the Brits is their incredible wit and sharp tongue. I enjoy learning how you are so capable. Is it from life experiences (auditory), school, or simply being well read? Maybe you can help me understand by explaining how you came up with the phrase "not enough room in the margin". I completely understand it and through research, I have an idea of where it came from. But, I am curious how it was seeded in your mind. Was is something you heard from others or something else?
Pierre de Fermat wrote it in a book margin in 1637 saying he had a marvellous proof tgat there are no solutions to x^n+ y^n= z^n where x z y and n are integers for and n greater than two. A chemistry teacher told me about it when I was 12
Same chem teacher told me a mnemonic for the elements in the periodic table. He said "I'm going to tell you something you'll never forget". He was right
@@MachiningandMicrowaves That's pretty much what ChatGPT-4 told me. You were lucky to have teachers like that. For kids today.... It's a wonderful time to be alive!! ME: If I were giving a presentation on a topic and I said, "I have a mathematical proof on the subject but the margin is too narrow to contain it.", what would I mean? GPT-4: If you were giving a presentation on a topic and mentioned, "I have a mathematical proof on the subject, but this margin is too narrow to contain it," you would be alluding to a famous historical quote attributed to the French mathematician Pierre de Fermat. In the 17th century, Fermat wrote in the margin of his copy of the book "Arithmetica" that he had discovered a truly remarkable proof for his Last Theorem, but the margin was too narrow to contain it. In the context of your presentation, you would be making a lighthearted or humorous reference to Fermat's quote. You would imply that you have a convincing argument or proof for your topic but, for some reason (such as limited space or time), you cannot present it in full detail at the moment. This statement might be used to create interest or intrigue in your audience or to emphasize the complexity of the subject.
The pronunciation of the three I can always recall are: Scanty Vancra Manfee Connie Cousin. Nam Galsipsclar. Libeb Ker Nof knee, although in my head it has the correctly-capitalised element symbols. He did have one for the second row of the transition metals, it went something like Why Zero Noble Mothers Teach Rude Ruth . Somehow I can remember the groups accurately. I can't remember the Actinides, but I remember it was mildly obscene, and therefore of consuming interest to a 12 year old
Thanks for the great video and explanation 👍 If i can give a tip on machining brass and bronze…. Use hss cutters. Insert give a rough finish as clearly can be seen and heard in the video. Hss steel needs a lot less tool pressure and will cut materials like brass easier if you make small depth of cut/ passes . Carbide inserts are not really sharp and are technically not cutting but rather more a controlled crumbling. Therefore carbide inserts need more constant tool pressure / cutting power to give a smooth surface finish and therefore need more infeed per pass to stop squeaking 😀. I hope it makes sense…
I use special uncoated polished carbide high-rake cutters that are designed for finish machining on aluminium. They are razor sharp and totally unlike the negative-rake carbide inserts used on hard steels, They lose their edge quite rapidly on brass though, and I think this clip might have been with a tired one! I have to lap them on a diamond wheel to get decent tool life. I do sometimes use HSS, I have a Deckel/Alexander D-bit grinder, but 99% of the time, the finish I get with the good quality high positive uncoated inserts is as good or better than with HSS. I really need higher surface speeds than my old lathe can manage to get the best results on anything under 20 mm diameter. When I'm using a fresh or re-lapped insert, I can get a really nice chip formation without any of the squealing. I do grind a lot of carbide tooling and D bits for making microwave feedhorns. The convenience and dimensional repeatability of inserts is very attractive, but yes, I should grind more tools! (or at least keep them lapped)
Ah! From the time I first heard of this thing I understood the concept of backscatter and the concept of "sound can change the properties of an RF circuit" but nobody ever explained how the thing *worked* beyond that. I figured it would have to be FM (but how exactly?) or PM (but wouldn't the effect be ridiculously small when you're talking about μm of movement against cm of wavelength?). The reality is that the soundwave is doing "FM" on the resonator frequency and then the probe is acting like a *slope detector* (sans the actual rectification part, which happens elsewhere) so that what comes out is AM. In normal application, slope detectors are just about the dumbest way of demodulating FM, but sometimes "dumb" is absolutely beautiful.
The movement of the membrane is around 10 nanometres on a gap of 25 micrometres, so about 0.04%, but at 1 GHz, that amount of change would affect the phase of the retransmitted signal slightly, but I couldn't detect any PM. That could just be the capture effect of the strong illuminating signal, which I could null out to -75 dB after many hours, but may have still been much stronger than the reradiated signal. One day I might set up a more robust experiment.
I have to say I really love these types of video.. I love your shop work too, a mix of this and the shop stuff, but minus the AI GF Secretary thing would be amazing.. I should say I've missed a lot of stuff in the last 6 months or so, I got put off by the pretend AI woman thing.. I'm not saying any of this because I feel that my opinion matters in any way, or indeed is a reflection of your audiance, but I kinda think saying "Well done", and "I like this" is more productive. Thank you for keeping up your efforts, and adapting, to find the balance between what is pleasurable for you to make, and what's pleasurable for the wider world.
AIMEE did get a bit out of hand, but that's my personal demons fighting to make themselves heard. As a narrative device, taking the role of the all-seeing, all-knowing Narrator in classical Greek plays, AIMEE gives me a way to defuse the potential for sounding smug, but also saves me from re-recording on-camera video segments. I recorded a section of this one that I spent hours on, but mispronounced some words. By then I'd moved all of the camera gear and changed lenses etc, and it was 4.30 AM and I was tired, so I just wrote a TTS script and had AIMEE scold me for saying something silly. In the end, I ditched the whole segment though! I've lost a 10 minute piece to camera about the 150 picometre Van de Waals diameter of Nitrogen molecules and their mean free path and mean spacing, with lots of science about the interaction between the membrane and the molecules in the air. I can't find the audio, video or even the text files, yet I can remember clearly doing the initial rough edit of that segment. I might find it again and put it out on Machining and Microwaves Plus if it looks interesting enough to resurrect.
Fascinating Neil. I am only now realising how many hundreds of hours of work you put into this. I guess you didn't sleep much! When are we getting the "What's on Neil's shelves video"? Cheers, Fraser MM0EFI
Tremendous. What a dive into the world of passive RF. Absolutely still with you though my field lines and circuits is a little rusty. My mind boggles at how tight the design was at the limit of available equipment. Just how far we have not come in all this time. Well, with what we know. Who believes the narrative on the telly after watching this ? Great work. A credit to society for producing content like this.
As someone with more technical ability than many and the frustration of NOT always being able to share my knowledge with those who dont quite drok what i am saying..... My hat is off to you good sir! Excellent discussion and clarity! To be truthful i have wondered about the engineering of these devices for some time, i now understand them! Cheers!
I am trying to improve my skills, I'm working hard on getting animation overlays out of OpenEMS/Paraview 3D field dumps on to video of real objects with a moving camera position. I messed up the audio at one point because I only have one working ear, so didn't know the right channel had disappeared, so headphone users got vertigo! I need to work on my color-grading skills, lighting and macro stacking, and get better at writing tight scripts and making better designs and doing more effective research. Right now I'm in the USA at a microwave radio conference talking to immensely bright engineers, academics and makers, so I have even MORE ideas to add to my growing list of upcoming productions. Thanks so much for watching and commenting, it really inspires me to improve
I had a Kallax and I nicked the idea from VidIQ and three or four other channels before I even knew about Alec's channel. He has better hair and nicer LED lights.
There are "only" five thousand words in there. Many are duplicates, but there are SO many sentences. Those are the real menace, sentences. 158 words per minute on average. That's faster than my mother could take shorthand, she says, but she's found the "play speed" option to slow me down if I get too fast for her ears. Hi mom!
The fact they did this before computers and with almost no 1ghz radio in existence is amazing. i really hope the engineer that built it has notes somewhere out there
See my previous video for the background, Termen/Theremin was in the US in the late 20s to late 30s and has some patents to his name, but was of course working in a sharashka after being interned on his return to Russia. I guess that somewhere in a hallowed corner of the KGB archives, there's a well-preserved and revered file of NKVD papers with all of the juicy details carefully recorded.
WOW.... I was thinking it was gonna be months before you released this one, and it was release in such a short time, and PACKED with amazing info. Thank you so much. I was on the edge of my couch in complete amazement. I have a few questions or thoughts rather... No. 1 - The guy receiving the signal, must have been highly busy in making adjustments, as the almost but infinity of variables were constantly changing, like people in the room, how many of them in the room, humidity, seasonal change, temp change of the morning to noon to night time and so many other issues that I myself am not even smart enough to think about. No. 2 - (I will need to ask my father more details and what is allowed to be covered of things my grand father had done in his past days 50 to 90 years ago) But, Brass is a common thing around the world. Brass has many special property's that are beneficial to the wellness of mankind. Please note, this is something I know very little about, hence, I will see what my father remembers from my grandfather. Brass as we know it today, comes in a handful of alloys, all serving a standard ideals in manufacturing and the finished products requirements. Brass back in the early days, about early 1900's about WW1 and for sure, WW2 ,used to have a SIR name, of YELLOW BRASS, for the alloy of brass we all have grown to know and enjoy for sanitary or anti-bacterial purposes and ease of manufacturing. But back in the day, there was a few other "BRASS'S / BRASSES" out there that were in common alloying manufacture. The second brass alloy was called orange brass and it's alloys served a particular need and had a certain health risk in the manufacturing process and machining aspect of inhalation risk of micronic orange brass / dust particles, which I do not remember the factual numbers but was like 100 times more risky to deal with, as compared to the "NO RISK" to deal with of yellow brass. Then, there is the RED BRASS, which is 100 times more vial then the orange brass. (Please note, these numbers are not factual, but merely just to example of the pro-rated scale of volatility or risk factory when dealing with each alloy) The RED BRASS in most common manufacture (back in the day) was used to make the commutator hub, and or brushes in AC & DC motors and slewing rings. RED brass had a fair wear factor, less arcing, fair heat capability and transfer, among many other strange property's. But the one that it was prized for what it had a weirdo resonance frequency and it would change magically is it was being used as a load or passing current through it. Please note, I do not know all the fancy stuff with this alloy. as it was way long before my time. ORANGE and RED BRASS back in the day used to be accessible to anybody in the USA from your local supplier or smelters. But if I remember correctly, it became illegal to own or maybe illegal to manufacture in a professional setting back in the early to mid 70's. Well, me having only just been born in 1976, I wouldn't hear of such a thing until about 1998 or so, when I was reading cover to cover my first Machinery's Hand Book the 5th addition as that is all I could afford. While trying to get up to speed with metallurgy and what makes the world tick. I needed my fathers help with many questions, which he helped me out so much as it was just second nature for him to already just know. I was in the process of learning about cutting fluids and lubricants, new and old school ways, like pig lard for some of the sticky metals, as strange as that sounds, which is then when I started down the path of which alloys are stickier then others, and is how I seen the various alloys of brass. Hey dad, what is the difference between the 3 alloys and how are they typically used and why can't I find any at my local supplier, let alone, they have never even heard of that either. My father just laughed and the story time began. I am sorry for the novel here, but, I can't help but to think, if orange or red brass was used in this type of project all based on some of the story's I was told. The resonance frequency and Q of this toxic man destroying metal alloy, I am betting did play a role in this type of stuff. Maybe perhaps, not this particular unit, but, I sure can't help to wonder now. I would like to learn more about this now.
I use CZ121 brass, but also Naval Brass. It's not good for RF as the bulk resistance is much greater than copper, aluminium, silver of gold, unless you electroplate it with at least six skin depths of silver. A lot of old brasses had arsenic and tin. Red Brass is what I think we call gunmetal (C23000 Copper)? There are some with manganese too, and lead. The difference between brass and bronze is quite blurred as well.
@@MachiningandMicrowaves Oh, arsenic, YIKES... All I could remember was that is was seriously bad for those old school machinist's to mess with it, but were asked to continue for a war effort, which later turned into the "getting the company back on track for civilian production"... pretty crummy. Wow, arsenic.. that is so messed up...Thank you for the info and follow up.
The recordings I made from the bug in fairly ideal circumstances in my lab and garden after SIX HOURS of setup are at ruclips.net/video/GyryQltyDwA/видео.html
For those who have asked, Pierre de Fermat wrote a note about having a wonderful proof of a thing, but the margin of the book he was defacing didn't have enough space. He wrote it in the margin of his copy of Diophantus's "Arithmetica", perhaps in 1637. There's a reference to the margin note in the 1670 edition from Fermat's son saying:
"Cubum autem in duos cubos, aut quadrato quadratum et generaliter nullam in infinitum ultra quadratum potestatem in duos eiusdem nominis fas est dividere cuius rei demonstrationem mirabilem sane detexi. Hanc marginis exiguitas non caperet."
which my grasp of schoolboy Latin almost renders understandable. My esteemed friend Google Translate refuses to do it on my phone, but typing it in results in:
"Now it is right to divide a cube into two cubes, or a quadratoquadra, and in general no power to infinity beyond the square into two of the same name, of which fact I discovered a wonderful demonstration of course.
THE SMALLNESS OF THE MARGIN WOULD NOT TAKE IT"
upload.wikimedia.org/wikipedia/commons/4/47/Diophantus-II-8-Fermat.jpg page 61, just under Quaestio 8
Also, I didn't go into how the demodulation works. I need to cover that in detail another time, but it goes a little something like this:
If you have a diode in its square-law region, the current is proportion to the voltage squared. If you then drive it with a mixture of a pure tone at 1 GHz and the modulated signal, then feed the output into a resistor, the voltage across that resistor is the sum of the tone and signal, all squared. The tone is just B*cos(omega*t + phi) and the modulated signal resulting from a simple audio tone is the usual AM expression A*sin(omega t)+ 0.5Am(sin(2pi(fc+fm)t+theta + sin()2pi(fc-fm)t-theta)
omega is just shorthand for 2pi*fc, fc is the 1 GHz carrier frequency and fm is the audio modulation frequency. A and B are just the amplitudes and m is the modulation index (0.05 or so) Now add the two together and square the result using the diode transfer function. You get an exciting mixture of results! After a load of trigonometric identities and wrangling, there are some components with sin(2pi*fc+phase angle) plus a load of other stuff. Run the combination through a diplexer to take anything higher than 3 kHz into a dump resistor and everything below 3 kHz but above 200 Hz into an audio amplifier, and you recover the original audio signal. If there is also some phase modulation, that results in multiple additional sidebands around the 1 GHz carrier, although at a low modulation index, the result is pretty much the same as AM. At higher modulation indices, the results are more complex, with Bessel functions of different orders causing a spread of sidebands rather like in FM. However, they are mostly removed by the low pass filter, except for the low frequency parts of the higher-order sidebands. The amount of phase mod is (luckily) quite low. I hope you can see why I rather glossed over THAT lot, but it would be fun to do a ten minute vid about it at some point, to exercise my MATLAB, Manim, MathCAD and storytelling skills!
It was beepin over the AM. Turned off it was beepin. Un plugged it was still beepin. I never could figure that out except like a hendershot tank circuit. What do you think? Im a schooled electrician and that scared me like a movin planchette on a ouija board
Guess what I realized after watching this video?
I realized that I didn't understand anything about it.
But he has a good colored shirt!
I have many different coloured shirts, there's probably some sort of coded message in the shirt I choose for each video. But I'll leave that up to the cryptographers to decipher
@@MachiningandMicrowaves I suspect the message is: The Soviet Union (bright red on your shirt) makes people see things as Black and White or at least gray. One Estonian writer called the Soviet Union the "Empire of the absurd".
@@MR-ub6sq I think my dogs see it all as grey.
I didn’t even know something like this was possible without active circuitry. A purely mechanical microphone with no on board power source that can “transmit” wirelessly is just mind blowing. The ingenuity is incredible
You can of course use reflections from central heating ducts, metal radiators and filing cabinets, but this was the first publicly-divulged case of a cavity resonator microphone
@Chris Lund What ???
It's how rfid tags work...
@@UNcommonSenseAUS Passive RFID tags use a slightly more subtle approach, using rectification like the later EASYCHAIR MkII devices but then using load-pull techniques in the near field rather than changing the resonance and re-radiating a back-scattered far-field. RFID tags are immersed in the reactive near field of an inductor driven by an exciting oscillator, where they can then change the loading on the oscillator. That is detected as changes in the amplitude and phase of the exciter, rather than collected by a separate receiver. The tag stores the rectified energy and activates a chip, which then changes the loading on the receive coil in the tag. As it is in the reactive near-field, the exciter "feels" a changing load. The changes are made very rapidly, so the data rate can be high, but very little power is required. Other tag types such as those used on toll roads use active transmitters to gain much larger range.
in clearance areas, your not allowed to bring radios or anything as if you talked even with a radio off could push sound agianst the speaker and transmit it electroniclly.... spy stuff is crazy....
Can never get over how much an absolute genius Theremin was. Been interested in the Thing for years, and absolutely delighted by these videos.
His life story is pretty amazing, the lad met Lenin, knew Einstein and Charlie Chaplin, was (probably) into money-laundering to fund espionage ops in the Americas, appeared at Carnegie Hall, was thrown into a gulag, became a celebrity again and joined the communist party after the Berlin Wall came down "because Lenin asked me to". They don't make folks like that very regularly.
@@friedrichhayek4862
😔Sadly, genius and morals are not necessarily correlated…
@@friedrichhayek4862 Just because you don't like his alignment, doesn't make him evil.
@@klin1klinom unfortunately because they're commies, it kinda does
@@friedrichhayek4862 are you saying Theremin is evil?
"64 teeth per banana" is the most accurate description of what life is like in an Imperial system that I've ever heard.
Please see Banana for Scale.
@@xenoxaos1 That's a left-handed banana, my calibrations will be off.
CEE Kurtis is the custodian of the International Standard Banana. Handedness in banana standards is always a problem. Chirality sux.
@@MachiningandMicrowaves Not to mention which banana you use. The yellow comes in a few varieties, and by me there is a purple one, the Natal wild Banana, which is totally different to the others, and also has seeds in it, unlike the yellow sports.
Luckily there is nowhere in the world that uses the Imperial system for anything other than pints of beer, and occasionally milk. (If you think the US does, then ask yourself: why would the US adopt a system of weights and measures proclaimed by George IV, son of the much-detested George III, in the 1820s, 50 years after the Declaration of Independence, and in the shadow of the war of 1812? If you said "they wouldn't", you're on the right track.)
Having chopped up a great many microwave ovens, I can definitely assert that resonant cavities are nothing but plain and simple black magic! This series is rather fascinating... my understanding is still only growing with the tiniest of baby steps. But your delivery is keeping me intrigued.
I love how you put your words together. I feel the same exact way you do but would never dream of being able to put it into words the way you have. I love it
What I believe, all the engineering regarding radiofrequency is taught backward, bot in schools and some Universities. They show a resonating cavity, a waveguide or a magnetron, and try to explain how they work by mentioning electric and magnetic fields plus some random formula. All the students feel confused, and sometimes inadequate. The only way to learn the "magic" of RF is first grab the math of fields, then the Maxwell equations, and learn how to write the right equation for the device you have, or want to design. It may take six months of learning in the worst case, but after designing the right magnetron, or the proper resonating cavity will be no more difficult than writing down your weekly shopping list.
To learn correctly you cannot avoid following the right sequence; whoever propose an easy method, where you start from what is most interesting, will be wasting your time...
I dream of Gyrotrons. Gyroklystrons even. Those are beyond amazing, with a magnetron just to create a source of electrons. Tens of kilowatts of mmWave power, just from electron gyration in a magnetic field. Marvellous
Most of what is taught in universities is not very connected with the real business of devices. I was asked to act as an industry appraiser in the accreditation of a new Uni course in my professional area (cybersecurity). The course was ten years out of date and was designed to be easy to teach and assess, rather than giving the students a grounding in the real world. I was going to show the analytic solution for the capacitance of a small disk close to a large membrane, but it's furiously complex. All of the examples I recall doing when I studied electronics and physics were for ideal situations with lots of symmetries.
@@MachiningandMicrowaves I learned way, way more about the physics of RF devices and propagation from getting my ham radio license than I ever did in school. Much faster, too. Applied information is way easier to absorb and synthesize than abstract information.
This device is pure genius. How fast we went from the discovery of radio to what is essentially a remote-modulated radio transmitter. Even the technicians operating the listening station had to have a strong grasp of the theory.
I passed my foundation ham exam today, but I was NOT ready for the intensity of science about to be dropped on me in this video. I feel thoroughly inadequate, but I shall keep endeavouring to understand everything after your introduction.
I doubt that more than a few percent of hams would follow it all, I'm working in such a tiny niche area of radio. I do more mainstream things as well, like using moonbounce and Auroral reflection on 2 metres, plus meteorscatter, but those are probably very niche areas to most hams. I also mess about on 136 and 472 kHz, red light comms and most bands from 1.3 GHz and up, plus 1.8 MHz QRP CW and digital modes. Working the USA from the UK with five watts or less on 1.8 MHz is a hugely enjoyable challenge. The glory of the hobby is that there is a vast amount of different fields of endeavour that you can play with, and a near-infinite amount of detail that you can investigate if you like that sort of thing, or just get one any use radio if you don't want to do deep dives. One of my friends decided to check the doppler shift on the QO100 geostationary satellite to monitor how it was saying on station out in the geo belt. I like using aircraft scatter to bounce my 10 GHz signals over the North Sea into mainland Europe. I think less than 0.1% of UK hams do this stuff that I find fascinating. They probably have similar niche interests that I know nothing about. The hobby has been fantastic for me since I made my first radio back on 1969
@@MachiningandMicrowaves I'm right with you, though the lower (super DC), leaves me wondering who you have to email to gain a contact. I'm 23 -3cms this way via QO100 too. All good fun. Tony G6YPK
@@educatedmanholecoverbyrich8890 There are very active groups.io forums like rsgb lf group that show what activity is going on
I suspect the pressure equalising hole would have been even more important for atmospheric pressure changes that could otherwise cause a significant shift in resonant frequency, or even cause the diaphragm to push up against the centre pillar in the resonator and stop any modulation. In fact just getting the resonator assembled might be impossible without damaging the diaphragm from overpressure.
Excellent point. Although the threads are rather leaky, I suspect they would have used wax or something as a thread lock and that might have sealed the thing too well.
@@MachiningandMicrowaves On drilling such a hole using a tiny spade bit, I hand made a 0.3 mm drill (for use in brass) out of a wire "hair" from a stainless steel wire hand brush. It was surprisingly effective and easy to pull off with only the hand tools in my back shed and a magnifying glass.
@@lordchickenhawk Excellent! I've certainly made tiny spade drills from carbon steel wire, but only for plates 1-2 mm thick. Huge respect to the folks who did that 40x diameter hole
@@MachiningandMicrowaves As you say... it's always that ratio that is the impressive bit!
In his book Spycatcher, Peter Wright described how fragile the diaphragm was - it could barely be handled at all with tweezers!
This is my first time watching one of your videos and the amount of references and jokes you manage to fit in while still being entertaining and informative is absolutely insane. Good job. You got a new subscription.
I suspect he has the dad superpowers.
I'd never heard of this 'passive' bug but what an ingenious device and perfect explanation of the LC operation!
Thank you SO much for these eye-opening videos. I did not know of this until you brought it to my attention. I find the ingenuity behind such simple yet effective devices amazing.
There are SO many more of these amazing spying devices, I'm going to have a look at some of them later this year. None of this would have happened without Heather from the Radio Society of Great Britain, who put me in contact with the BBC TV team making the Secret Genius of Modern Life series. It's been an amazing journey of discovery
As I have some very slight knowledge of some of these topics, I slightly understood this. Fascinating. You deserve a lot of views for trying to explain something very technical with enough detail that the interested person with a bit of physics/electronics knowledge can follow it.
I get a lot of folks moaning that I use too many words, well they can go watch Shorts. I like words! It's been a fascinating journey through history and tech and science
I read about it in a book by Peter Wright a good 30 years ago. There was also a description of another high tech magic - locating Russian spies by identifying them by overloading the hetordinates in their receivers with the signal transmitted from counterintelligence cars from the street. If this overload created a dip in the frequency suspected to be spy transmission, agents had confirmation that someone in the building was listening to spy transmissions. It did not require any mechanical operations, however, it was purely electronic manipulation.
I rather cheekily call him Peter Wrong, but his ghost-writer did an excellent job with a difficult subject. Rather a lot of twaddle and bunkum in the book, but since then a HUGE amount of detail has emerged about all sorts of TSCM and technical ops. I'll certainly be making some videos about the ones involving machining and, er, microwaves. I might need to be a bit flexible about what constitutes "microwaves" if I can get hold of a working IBM Selectric typewriter to try making a GUNMAN project device and supporting infrastructure! next spy device on my list is an EASYCHAIR Mk 2 I think
Exquisite work! Just shows how much nuance can be between a popular explanation and the actual working system.
Thank you ! While I knew the basic principles behind the great seal bug, seeing you construct one, brings it all together. Trig and waveforms , headaches of my youth. Only time in my life that the same problem was presented 3 times and I failed to solve it all three times, embarrassed I was but did answer the rest of the exam correctly. Sometimes a concept just fails to gel. Look forward to watching more of your videos. They tickle the dormant Grey cells , as ancient connections that laid unused, reconnect . Take care.
I understood exactly 0% of what you were talking about, but it's really interesting that you understand it. Lol. Hope you're having a fantastic Easter.
I've always wanted to deep dive the Great Seal Bug but never got around to it, thanks for the explainer! Also -- I think I see a familiar directional bridge on the shelf behind you!
Oh yes, a very nice and useful bridge it is too!
the fact that i understood a fraction of that is a testament to how well you've broken up the complexity of it into nice digestible chunks.
"I have a wonderful mathematical proof of that but these margins are too small to contain it." I'm dying. Haven't thought about that in sooo long
Is that a Fermat's last Theorem reference?
"I have a wonderful mathematical proof for that, but this margin is too narrow to contain it"
Ahh, yes, a quality reference sir. You are a man of taste.
Thank you for sharing this. I like the level of thoroughness you go on your videos. Never heard this type of bug before. You made my Sunday
The theory underpinning this device is just remarkable. A superb explanation. Such ingenuity boggles the mind.
I'd heard the story of the bug long ago, but the technical specs were nice to hear about.
Ahh man, ive really been enjoying these videos. you write them very well, and i love the little hints to other scientific quirks (like not fitting your proof in the margin, absolute gold!)
I am blown away.
I have wondered how that bug worked for years.
Speaking of years about 25 years ago I got an Associates degree in electronics technology.
Had youtube existed back then and I had seen your video then I would have understood hat you were talking about.
As it is now I got the basic brushstrokes of what was going on and found them fascinating.
Liked and subscribed.
Will be checking out your older vids and waiting for new ones.
I wish I had time to make more vids. Real Life keeps intruding. I have some more detailed testing of this Bug to film, then later this year I'll be looking at one or two of the other spying devices that used a slightly different method of operating, but still without any power supply needed. First though, I have a backlog of machining and testing of antenna feeds and all sorts of mechanical contrivances to get made for microwave filters and antennas and moonbounce systems
"weleda hat recht. der beitrag ist alles andere als objektiv. herr aust stellt das mittel nicht lege artis her. es muss zunächst stundenlang verrieben werden"
Dr.. Aust macht das vollkommen richtig. Verrieben werden in der Homöopathie nur Substanzen, die weder in Wasser noch in Alkohol löslich sind. Kochsalz ist aber wasserlöslich....
"frau grams geht nie darauf ein, wieso die fürsorgliche mutter beim kranken kind mit dem falschen mittel keinen erfolg hat. "
Die Krankheiten die Mütter bei Kindern homöopathisch "behandeln" sind üblicherweise Krankheiten die in den allermeisten Fällen von alleine heilen.
Es gibt da einen natürlichen Krankheitsverlauf der meist so aussieht dass sich der Zustand des Kindes zunächst zunehmend verschlechtert und danach wieder zunehmend verbessert.
Je nachdem in welcher Phase man mit der homöopathischen Behandlung beginnt verschlechtert sich der Zustand anfangs noch weiter (was Homöopathen dann als angeblich erwünschte "Anfangsverschlimmerung" bezeichnen oder sich alternativ damit herausreden, dass das falsche Mittel gewählt wurde) und sobald die Phase der Besserung erreicht ist reden sich Homöopathen ein, dass sie nun das "passende" Mittel gefunden hätten.
Dabei haben die verabreichten Mittel den Krankheitsverlauf gar nicht beeinflußt.
Das ist wie Regentänze aufzuführen damit es regnet. Regnet es nach dem Regentanz nicht dann war es eben der falsche/unpassende Regentanz. Und regnet es nach dem Regentanz dann hat der Regentanz natürlich gewirkt.
Ist ja klar.....
"außerdem fragen sich skeptiker nicht, wie die mittel ausgezeichnet wirken können, wenn dem tier das mittel heimlich gegeben wird, gar einem ganzen kuhstall. außerdem wirken die mittel auch bei pflanzen, patienten im koma und bei skeptikern"
Und Homöopathiefans fragen sich nicht wie man mit Pflanzen, Tieren oder Patienten im Koma eigentlich das von Hahnemann zwingend vorgeschriebene ausführliche Anamnesegespräch führen soll um das "passende" Mittel zu bestimmen.
Und wo bleibt den der viel genannte "ganzheitliche Ansatz" bei dem jeder ganz individuell für ihn passende homöopathische Mittel bekommt wenn man einen ganzen "Kuhstall" mit dem gleichen Mittel behandelt?
".- ob besagte gynäkologin nur einen schmalspur-kurs besucht hat, können wir nicht sagen. freilich ist eine gescheite diagnostik wesentlich."
Eine gute Diagnostik ist natürlich wesentlich - nur findet die in der homöopathischen Lehre nicht statt.
Die Homöopathie interessiert sich nicht für die Ursachen von Krankheiten - die "Therapie" erfolgt aussschließlich auf Basis von Symptomen und deren Begleitumstände. Wodurch diese Symptome verursacht wurden ist für die homöopathische Behandlung belanglos und Hahnemann hat sogar davor gewarnt seine Zeit damit zu verschwenden nach solchen Ursachen zu suchen - zu seiner Zeit durchaus verständlich da man viel zu wenig wußte um realistischerweise durch Ursachen der meisten Krankheiten überhaupt zu finden.
"- eine berliner krankenkasse hatte angegeben, wieviel sie für homöopathie ausgibt. ca. 1%. also ein winziger bruchteil der kosten für allopathika. so was unterschlägt der beitrag natürlich, die "prophezeiung" der weleda bestätigend. :)"
Die Gelder die für "fliegende Teppiche" ausgegeben werden sind auch geradezu winzig im Vergleich zu den Geldern die für Flugzeuge von Airbus oder Boeing ausgegeben werden. Ob das daran liegen könnte dass es mit den Flugfähigkeiten fliegender Teppiche nicht weit her ist?
The brilliance is in the simplicity of the device. It is so simple to not degrade for hundreds of years. It could still operate, had the Americans not been electronically vigilant. Maybe this type of device still operates in the embassies of, say, Nigeria ?
Yes a Gem of a video and I have just watched a few more... you may never know who is watching and appreciating your work. I sense your long hours in exploring and thinking through a project and of course the many midnight hours in the workshop... Time is precious but the eventual satisfaction of achieving is priceless...
I did follow and very much enjoy your explanation of the physics involved.
It is a shame to hear of your travel plans falling apart and that must be mega frustraing....
However, I wish you well,
Thanks
John Alex'
I’d never associated the term “condenser” in relation to mics with the old term for capacitors, that’s a real paradigm shift. Loving this series.
My teacher liked the term "condenser", or Kondensator. He mentioned it was the German name and was only replaced with "capacitance" and "capacitor", because Germany lost in the WW2. In fact, we still had two choices for our text book, which in my case ended up to be "Fields and Waves in Modern Radio" by Ramo and Whinnery (???). Some students picked the German language alternative. Then, in the final tests, there was a funny incidence. The professor had followed the Ramo & Whinnery book wave sketches, which we dutifully copied from the blackboard. This one smart student caused the professor to complain that while that student's result was O.K, there was something odd about his sketch. The student replied "Yes, sir Professor, you drew the blackboard presentation in American standard 3-D orientation. I used the European standard perspective". Evidently he was the only one in the group (including the professor) who had completely mastered the idea. I was lucky to be in his 3-student team in our lab exercises.
Very cool!
Some microphones work purely on the condenser principle, where the movement of a thin plate in response to sound alters the impedence of the microphone, as explained in video.
@@chrissmith2114 Theremin would have been well aware of developments in condenser microphones, although he left the US just before the cavity RF condenser microphone patent was published. Condenser mics using DC bias with a series high value resistor to give audio voltage out as a result of the charge between the plates averaging out as a constant number of coulombs, and when the membrane moves in, the capacitance to the backplate increases a tiny amount and as charge is capacitance times voltage, if the capacitance rises, the voltage falls. On average the capacitance and voltage stay constant over a second or so. The Bug design is pretty much a direct lift from the US patents that Termen spent much time reading. It's pretty certain that he was working for the NKVD while in the US. Fascinating story, there's an interesting take from some Russian authors, with a title like "Russia's Edison" that adds a lit to the story, although there are layers upon layers of disinformation
In Russian it is the same word - "конденсатор".
This is ingenious! No circuitry, no electricity but it still works? WOW!
You mentioned Physics Girl, it’s very sad what has happened to her 😢
Very grim, poor lass. I put a note in the description suggesting folks visit her channel
Wow. Fascinating. Simple device yet wickedly complicated.
This level of technical elegance is oft overlooked in modern times and is absolutely necessary for the next stages in computing. Thank you for sharing this extremely interesting and scientifically _sound_ knowledge!
I absolutely love this series!! With all of the incredible intentional engineering and design it took to make The Thing work, it makes me wonder how many random metal doo-dads in my house are accidentally a perfect audio/RF resonator, such as the Coke can I set on top of my vintage Disney lunchbox, along with a few wood screws and penny. I’ll guess I’ll never know. 😅
Almost everything, and not just metal things, dielectrics can also do this (a little)
jajaja...i was thinking something similar.
and i dont think the emiter about this interesting video needs a power supply.
just another metal with the same frecuenci in a electronic mesh.
@@MachiningandMicrowaves There’s a fine line between physics and magic!
I like the new format. I'm always happy to see a new video.
Such excellent work, the hours in research you have done along with the machining and I bet chasing down dead ends, keep up the fascinating work
I wish I had more time to do this type of investigation, but Real Life and the Day Job conspire to eat up my waking hours.
Brilliant description! If you read Teslas papers, you will see his circuits were tuned to resonance, just like tuning forks. He actually shows how the ground works as the tines of the tuning fork!
The Fermat margin joke really got me lol, good one
And also Blues Brothers.
I was hoping I'd get to make this comment 😢
I almost spit out my tea when I heard the margin joke.
About the 1ghz transmitter - there is a mechanical device called frequency multiplier. It is very bulky, but that allows to have a simple carrier like 125 Mhz that after a couple of multiplications gets to 1 GHz. On the other side you can have mechanical frequency dividers. That way you solve the electronics problem.
A *mechanical* device operating at 1 GHz!? or even 125 MHz? Not likely...
No mechanical components or battery? Only requires one Boris
You are giving a whole new meaning to "Cavity research".
The shame is that we will probably never know the names of the scientists and engineers who came up with such a delightful creation. With my 40 years of experience I grasp the concepts but with the modeling tools we have today we could recreate or even slightly improve upon this design.
At that time, in the Soviet Union, immediately after world war II it was pure genius and inspiration.
Eventually the us vs. them aspects of scientific discovery falls away to only leave behind the truths of a theory turned in to a workable solution.
@@Tishers The progress in many countries during the 1930s was extraordinary but the unique circumstances of the sharaska system certainly seems to have developed her white heat of technological progress. However, if you compare that with what was happening in other countries at the time it's not particularly remarkable. The list of scientist and engineers in the sharaska system is known, but the specialist clockmakers watchmakers and machinists who did the work may never be identified. There were very fast developments during the middle 1950s with a whole range of similar types of eavesdropping system. I'm working on a replica of the EASYCHAIR Mk2, but right now I'm working on something from 1925 that shows an extraordinarily advanced set of technologies being harnessed, by an engineer who stood on the shoulders of Giants and pulled together threads from multiple disciplines to produce something quite novel.
Leon Theremin.
@@I967 While it's well known that Lev Sergeyevich Termen was the brains behind the system, the question that Tisha raised was, I think, about those who did the machining work and electro plating and wood carving and all of the other associated trades involved in the project. While Lev was a skilled radio engineer, I have never read any references about him having watchmaking or precision machining skills. He was a highly practical engineer and there's a piece he wrote talking about seeing a lecture by Ioffe, one of his mentors, explaining the photoelectric effect without the usual mathematical formalisms. That really fired him up and put him on the path of invention, despite not being a hugely gifted maths or physics student. The names of those other specialists will, as Tisha says, probably never be known.
You need to visit museum of SVR (Russian intelligence agency), in it exist exposition about it with photos and people behind.
Museum is pretty old (opened back in 1970s), in it incredible lot of interesting things/stories.
@@juliap.5375 One day I hope! Polytechnic museum in Moscow has some other items from Termen's work in the 1920s, I'd love to see those too.
I just found this video in my feed and am blown away by the quality of the information and presentation. Immediate subscribe! Looking forward to watching your other videos, you deserve way more subscribers!
I feel hugely blessed to have ANY subscribers! I started this channel as a way to recover from the grief when my wife of 37 years died of cancer, and I was astounded when the first hundred subs arrived, then I put out a couple of videos that were sort-of OK and BOOOOM, it took off. This is only the third or fourth one where I've appeared on camera, so I'm still hopeless at being the "talent" as well as the camera op and sound engineer and coffee-brewer and editor and colourist and scriptwriter and researcher and roving reporter, not to mention electronic engineer, machinist, CAD operator, programmer, animator and Physics researcher. There's no time to sleep, but I'm having SO much fun. Just wish I could get on to a weekly cycle. Ideally I want to do a 24 minute vid every second week and a 10 minute one on the other weeks, publishing at a consistent time, but I have to fight my self-defeating ADD and crushing shyness all the time. I'm giving a lecture in the USA next weekend and haven't written it yet. No sleep for me tonight!
Ah yes, I understand these words. What they mean in this arrangement per se, no idea. :D
My mother says that all the time when she's talking to me. So do my Chihuahuas. Although they only understand important words like "walk" and "dinner" and "snacks"
Very interesting. To make sure I understand, it means that someone was nearby the ambassador's study to pick up the amplified signal by the bug. Thanks.
The receive station and recorders would be in a building over the street that was shielded from the transmitter building. Not sure of the details but I'd guess the transmitter was 140 metres away and the receiver a little closer. The operation would have been quite a team effort
I guessed it worked by slope amplitude modulation from the first episode. Your explanation is excellent. I have a working Boonton 160A Q-meter.
I'v seen a 260-A but never seen a 160A in the flesh, excellent!
I picked up a used model 260A Q-meter some years back ... fantastic tool for coil characterizing ...
I got the Fermat's Last Theorem reference and Blues Brothers reference. I'm sure there were others that I didn't catch, but I love that there was no explanation. If you get it, you get it. As a technical channel should be.
Maybe the metal was copper sheet and then silver electroplated to gradually bring up the thickness as well stiffen up the walls ?
That way the precision was not a machined process but a gradual build up through electro plating ?
Which would give you the ability to precisely achieve very accurate tolerances .
Also create many that were slightly different sizes to experiment with getting them working properly.
@@vainwretch The analysis by the FBI and Navy Lab showed it was nickel foil with silver plating. Copper and silver make terrible diaphragms because they are too ductile and lack the stiffness of metals like nickel. There is a complicating factor though which is that the conductivity at around 1 GHz of a very thin diaphragm, especially one made of lossy nickel, is rather high. The thickness was quoted at about 6 µm. If that includes the silver plating, it would mean that the skin depth would be far less than required to get really good performance. Generally you need about six skin depths. With the current dropping to 37% every 2 µm, it takes about six skin or 12 µm to get to negligible current levels. I suspect that the measurements given were possibly deliberately misstated.
@@vainwretch I think you are possibly right about the body being electroplated as an additional measure to improve the quality and precision of the fits. It was made of copper with silver plating on top, and with silver being slightly self lubricating although not as good as gold, it would have made sense to the RF engineering side of Termen's mind to get the dual benefit of variable thicknesses of plating
it would've been relatively straightforward for them to have produced an electroformed nickel foil using a slowly rotating cylinder in an electrolytic bath. I have a 1 kg piece of titanium round bar that one day I will use to make a silver plated nickel foil using two separate electrolytic processes on the same material.
I was in the Navy and attended advanced first term avionics classes which go into advanced topics like RADAR and Microwaves. Klystrons, magnetrons, and waveguides were always kind of magical. They either worked or they didn't. It's not like we were going to troubleshoot the Klystron down to the component level if the unit is bad. We would, of course, determine if the unit really is bad or if one of the inputs were bad, but things like that are remove and replace. I worked AIMD and things like that pretty much immediately went to depot and probably eventually back to the manufacturer. We never saw them at the intermediate level. As far as RF is concerned, I have great respect for RF engineers and technicians. That stuff is just plain magic. I worked on SONAR gear and everything was in a nice low energy spectrum (audio), so I never had to deal with RF :D
Really enjoying this series. Cool stuff
I read Spycatcher and was also suspicious of the great seal bug, but your excellent description fits with my knowledge of microwaves.
"terrestrial globularity deniers"😂😂
Finally someone explains this in a language I can understand! Thank you!
I tried hard not to dumb it down but still make it accessible. I'm still a rank beginner at this RUclips nonsense!
Extremely thorough! Very informative, thank you for sharing your knowledge friend
I'm having SO much fun making these videos, even though I'm rubbish at it!
@@MachiningandMicrowaves not rubbish at all youre definitely a crown jewel in the youtube community. I can not thank you enough for all the work you put in to these informational videos!
This seems like one of the strange devices my CTO would build. Dude has the most fascinating devices.
When can we buy your replicas? Lol
Fantastic work, fascinating subject.
I'm thinking seriously about making a limited edition run with gold plating, in a presentation case, but maybe a watch-glass window in place of the membrane. Gift for the geek with everything
Brilliant video man!! I always wondered how they just about exactly did the trick and I had a pretty decent/correct idea of the principles, but the actual device was much more deceptively simple and elegant than I had thought.
A classic bit of design for sure. There's so much incorrect information out there, it's just amazing.
@@MachiningandMicrowaves well you've really demystified it in one way, but in another I'm only left with a deeper sense of awe at the elegance and simplicity of the design. So much so that even a cursory direct viewing of the object itself (not the seal but the inner workings) is not even obvious enough to immediately raise clear suspicion to an untrained eye, like say your average embassy removalist or cleaner, it could be mistaken for some hanging or balance device related to the ostensible gift. I'm really intrigued by the writing on the back of the item, can you make it out?
I remembered reading about this roughly 30 years ago in an old spy book when I was less than 10yo and being fascinated, remembering it very clearly ever since and so always happy to learn more whenever the subject came up. Your re-creation is impressive but so is the follow through, such as your animation of waves propagating down a street, really well done. I'm no radio whiz just your average RUclips viewer, but really impressed and appreciative of all your explanatory efforts. See, not having any expertise I had always imagined some passive device might have been like a little crystal radio set, I definitely expected perhaps a coil and a diode, never in my life would I have guessed something so arcane to the untrained eye, so while I admire your ingenuity in recreating it, what you've really successfully communicated is grounds for me to be impressed with the Russian originators, knowing all the practical, material and technological limitations the whole world faced at the time, let alone the Soviet union with shortages as they were, even (as you pointed out) limiting what was likely available for the two items of powered equipment between which the great seal formed the graceful nexus.
Oh sorry I see now it says "Property of division of security department of state" I was watching on a small screen-in-screen before I didn't realise it was easily legible.
Yes, they stuck that on the back cover. The original has gone missing and there are no available images of the main elements of interest around the bronze ring attachment of the membrane and the precise slot layout on top of the resonator
As a professional tech writer, I have to agree with you at 26:10. Too few of us around, and developers don't know how to write...
The suffering I go through with "documentation" written by surly coders who hate the job and do it terribly is just immense. I remember how well written the vast documentation store was that came with our big IBM systems. The thing I'm wrestling with at present runs mostly on Windows cloud servers, but was written by Linux techs whose idea of an example of usage of an obscure and poorly structured API function is to paste in a shell fragment, with the underlying surliness of a teenager aske to tidy their room but believe they are some sort of God-like Genius and think documentation is for simps. Yeah, those are what we call "Vulnerability Generators" in the cybersecurity world. Lovely. Documentation written by folks who can't write, don't want to write, and directed by management to spend as little time on it as possible. Great if you are looking for a way to sneak into a system. I think I am suffering from burnout and getting cynical in my dotage.
@@MachiningandMicrowaves Truly don't blame you. I'm one writer for an org of 250, so as you can imagine, most people are doing their own "documentation" and there is just no quality control. And if you survey developers on their #1 pain point of their job? "Crappy documentation" is what they say. How ironic!
This device is spectacular. Thanks for sharing
Watches entire video. Nods head repeatedly. So it was magic, then?
I concur with that sentiment most heartily, milord.
😂😂😂
Damn those slytherins
Have any of you guys thought that he just explained Havanah Syndrome? They weren't using an EM Weapon on the people who were stricken with it, they were bugging them and they were collateral damage.
The transmitter tube could have been something from us in the form of lend-lease gear too.
Lastly, what are the chances that they would heterodyne down to a regenerative detector? They're known for having a wide receive bandwidth that would make any sort of dynamic fluctuation in frequency less apparent, although at the detriment of being more susceptible to noise which may not have mattered nearly enough back then.
Have a read of the wikipedia page about Havana Syndrome and the Moscow Signal. The signal levels for the Bug are tens of thousands of time lower than those we all get from nearby wifi and cellphones. The only harm from RF is thermal heating, and that needs field levels that are well above the ICNIRP 2020 limits. Those Havana Syndrome effects are usually dismissed as shared hysteria or effects from infrasound, ultrasound, chemical treatments for Zika, stress and so on. It's fascinating, but there's not much in the way of evidence. RF signals are trivially easy to detect, and at least in the 3 to 10 GHz range, a few watts on your hand feels pretty hot, despite there being no measurable rise in temperature. Reasonably High levels of pulsed microwaves are supposed to be able to elicit a response from human ears, see the paper by Allan H Frey, (Journal of Applied Physiology, Vol. 17, pages 689-692, 1962) journals.physiology.org/doi/abs/10.1152/jappl.1962.17.4.689
Frey reported needing about 275 mW per square cm to elicit an auditory response.. USSR safetly levels win the mid-70s were 0.01 mW/cm^2 and UK limits were 10 mW/cm^2, so that's a pretty significant signal level. The illuminating signal for the Bug was around 2 million times weaker than Frey's experiment.
I think USSR scientists and manufacturing plants were entirely capable of making their own UHF tubes by 1943, but with a well-developed procurement network in the US, there are all sorts of possibilities as well as potential lend-lease sources and UK supplies. My stepfather worked on the Arctic supply convoys from the UK to Murmansk during WW2 and said there were lots of interesting-looking packing cases on some of the shipments. Also of course, there are potential supplies from Germany before 1941, but there was certainly a mature vacuum tube manufacturing base in various parts of the USSR in the 1930s.
Can't see any reason to use something other than a homodyne approach, although a self-oscillating regen might get injection-locked to the exciting signal and give much the same effect. I haven't seen any direct evidence, just multiple anecdotes.
I have no understanding in the field, but it's amazing, a sophisticated tool for Russian espionage from 1945 is still an enigma and a creditor after 78 years.
The FBI, CIA, Naval Laboratory and British intelligence folks knew how it worked soon after they received the bug, but it remained shrouded in secrecy and misinformation until the 2017 freedom of information release of all of the papers. A lot of internet sources are based on earlier articles that suggest some highly theoretical operating modes. I would say to all of them, just make some units and try them. That gets rid of speculation, when you have a real device, you see for yourself how it behaves
Это тайна бро. Никто не расскажет.
Reminds me of the Monty Python comedy skit with Leon Trotsky check into a motel and the clerk asking for your room do you want bugged or unbugged?
the shelf in the back gives some major @TechnologyConnections vibes, loved the video
@@jimmon89 Shamelessly stolen from VidIQ and several others with a Kallax. Then someone pointed out Alec's most splendid version with strong colours and overhead lighting instead of my pastel shades and rear curtain illumination. I got background envy. Also he has WAAAAY better hair!
Wow... A passive bug powered like an RF inventory control device in 1945... If they'd pattened it, they could be rich.
Who? Communists? :D Do you understand what means communism? Simplify: it is when everything in property of everyone.
Soviets rejected patent right (as result arrived funny situations, as example when US took Soviet movies and show to own people as it is US made movie, at the end of movie even show fake names of actors - it was legal because Soviets lived in copyleft ideology, you could without any restrictions to use any of they tech/product).
Another example - when you bought any Soviet device, with it you always got full scheme how it is designed and works, because again - any work (e.g. some engineering design) immediately became public property.
USSR had only two options: or make public, or classify as state secret. As example technology of stealth for jets came to US exactly in such way, fundamental work about it was openly published by Soviets.
Being free is more important than being rich
One has to admire the elegance of the device.
Wouldn't a negative inductance be equivalent to reciprocal capacitance? I think the seldom-used term for that (when applied to a capacitor) is elastance.
Elastance is definitely the word. I asked Google and got spammed by this pathetically-useless answer from Quora's rubbish AI bot:
SAGE: An AI bot writing "helpful" answers
What is the inverse of inductance?
The inverse of inductance is called "admittance", which is measured in siemens (S). It is a measure of the ease with which an alternating current can flow through a circuit. The reciprocal of inductance is called capacitance, which is measured in farads (F).
Spoken with all the authority of an opinionated and cocksure teenager who once read an incorrect Wikipedia page and mis-remembered it. Great.
Not "helpful", just completely and disastrously wrong. However, the humans on Quora are also mostly wrong, so it'll fit in just fine!
I liked the metal machining part very much, thanks.
You managed to make this so convoluted and difficult an explanation that understanding what you're saying is harder than making one. Trust me, I've made several, and got two to work. Had I heard this first I'd never have tried.
@@matthewhopkins7042 great stuff can you publish a video of it working? It will be fascinating to see what results you managed to get and how you dealt with the details of the diaphragm and plating and what resident frequency you found? Looking forward to seeing it!
did you manage to find a way of silver plating the diaphragm? How did you manage to tension the diaphragm? Did you use the original method with a bronze ring with an internal thread? What sort of percentage modulation did you achieve? What sort of receiver did you use and what sort of electric field intensity did you find was required to get a good signal to noise ratio? What did you find the optimum links of the external antenna rod to be? Do you have a recording of the sound quality? Mine was very echoey and, resonant because of using that stretched copper diaphragm which was definitely less than optimal.
On your other point, I tried to be a scientifically rigourous as possible within the constraints of a relatively short video that wasn't an academic lecture. There are several other videos that talk about the mechanism of how the bug worked in a much more general way, so I am not going to apologise for attempting a fairly rigorous treatment. I'm not a professional presenter or lecturer or scientist. I'm just a hacker who makes interesting stuff in his shed!
@@matthewhopkins7042 Do you have any detail, recordings, photos, video or published results you are willing to share? I'm aware of two or three other makers who have created working models, it would be great to add to that body of knowledge with your results
Understood not a word. Enjoyed every minute.
Transmitter likely was actually US made, from Lend Lease, and the receiver was probably made that way as well, using cavity filters made from brass, who probably were chosen so they would roughly track the cavity temperature wise, so were probably kept in a nice heated room to mimic the office temperature. Tuning likely was very critical, and used multi element Yagi antennas aimed at the room in question, with probably a tiny feed to the receiver, making stability less critical, as they probably used another LO to mix with the received filtered signal, probably via a multistage cavity filter, to get the LO for the receiver. Stable LO at low frequency using a crystal oven was probably enough and low noise.
Then mix, run through a few crystal filters, and you have a reasonably stable system, depending likely on US made acorn tubes for RADAR, stripped from imported equipment, and US made test gear to go with it. The high RF signal for excitation probably was close to a TV transmitter harmonic, deliberately transmitted to cover the bug signal, but far enough that they could tune it out with filters in the receive chain, hoping to have the US think it was just a spurious emission from a badly made transmitter.
They certainly used TV signals to make the later systems like GUNMAN, but I doubt that was part of this design, they were just banking on nobody noticing. With a homodyne reciever, any issues of stability or frequency changes are eliminated, although of course you have to re-phase everything if you change frequency much. With enough signal, direct conversion to AF works OK, although I found with a lot of tweaking that I could also get it to work with AM on my Russian Malahit SDR. It's not actually slope detection of course, as the TX frequency is constant, but the amplitude and phase change with modulation. I tried to pull out the phase mod in FM mode, but couldn't get it to detect anything. I think a homodyne with a baseband filter would pull out the first order Bessel function sidebands along with the simple multiplication product that makes DSB AM. One day I should make a larger unit with a more controllable diaphragm and proper anechoic chamber to see what actually comes out when it's fed with a coax probe
soviet union was developing magnetron devices in the late 1930s and would have had access to klystron tube tech post 1945, also had indigenous vacuum tube manufacture pre-war, so i dont see why they would need to go scavenge for bits since they were quite capable of producing anything they needed.
@@andrewbaluk1663 True, but if they could buy cheaper than make it would be done, plus also the knowledge that they were spying on the US, with US made equipment, as well.
Great explanation of how everything worked. I've always had some level of wonder for how the device actually worked and this was enlightening.
God, I hate those tiny splinters when machining brass, they get everywhere... 🙄
Heres hoping Diane is getting better... 🙏
😎👍☘️🍺
Very interesting breakdown - and truly genius design!
I got the fermat reference
But did you get the Blues Brothers one?
I learned about this AMAZING STORY from the show "Dark Matter's Twisted but True" I loved that show. This story Facinated me and you covered it so in-depth. Really glad I found your channel.
05:40 ah Fermat's margin-al excuse
Well spotted!
I always wondered what magickery made this work, thanks for the explanation !
I always assumed there was a diode, acting as a frequency doubler to the incoming signal, with that doubled frequency modulated with the mic, and then retransmitted. This is much more elegant, and I assume, more efficient?
Horribly inefficient, but SO elegant! I'll be doing a deep dive on the Easy Chair Mk2 which DOES use a diode
@@MachiningandMicrowaves Yes, and a good demo of slope demodulation to recover an FM signal with basically an AM receiver. Horrid noise immunity, and very poor performance, but it can be very effective.
@@MachiningandMicrowaves but if you include a frequency multiplier it is easier to detect using a bug sniffer looking for harmonics !
Strangley the video bored me half to death, so I watched it again and loved it.
One thing I have always admired about the Brits is their incredible wit and sharp tongue. I enjoy learning how you are so capable. Is it from life experiences (auditory), school, or simply being well read? Maybe you can help me understand by explaining how you came up with the phrase "not enough room in the margin". I completely understand it and through research, I have an idea of where it came from. But, I am curious how it was seeded in your mind. Was is something you heard from others or something else?
Pierre de Fermat wrote it in a book margin in 1637 saying he had a marvellous proof tgat there are no solutions to x^n+ y^n= z^n where x z y and n are integers for and n greater than two. A chemistry teacher told me about it when I was 12
Same chem teacher told me a mnemonic for the elements in the periodic table. He said "I'm going to tell you something you'll never forget". He was right
@@MachiningandMicrowaves That's pretty much what ChatGPT-4 told me. You were lucky to have teachers like that. For kids today.... It's a wonderful time to be alive!!
ME:
If I were giving a presentation on a topic and I said, "I have a mathematical proof on the subject but the margin is too narrow to contain it.", what would I mean?
GPT-4:
If you were giving a presentation on a topic and mentioned, "I have a mathematical proof on the subject, but this margin is too narrow to contain it," you would be alluding to a famous historical quote attributed to the French mathematician Pierre de Fermat. In the 17th century, Fermat wrote in the margin of his copy of the book "Arithmetica" that he had discovered a truly remarkable proof for his Last Theorem, but the margin was too narrow to contain it.
In the context of your presentation, you would be making a lighthearted or humorous reference to Fermat's quote. You would imply that you have a convincing argument or proof for your topic but, for some reason (such as limited space or time), you cannot present it in full detail at the moment. This statement might be used to create interest or intrigue in your audience or to emphasize the complexity of the subject.
@@MachiningandMicrowaves A 118 word mnemonic, that you will never forget?? you have my attention!! Do share!! :D
The pronunciation of the three I can always recall are: Scanty Vancra Manfee Connie Cousin. Nam Galsipsclar. Libeb Ker Nof knee, although in my head it has the correctly-capitalised element symbols. He did have one for the second row of the transition metals, it went something like Why Zero Noble Mothers Teach Rude Ruth . Somehow I can remember the groups accurately. I can't remember the Actinides, but I remember it was mildly obscene, and therefore of consuming interest to a 12 year old
Thanks for the great video and explanation 👍
If i can give a tip on machining brass and bronze…. Use hss cutters.
Insert give a rough finish as clearly can be seen and heard in the video.
Hss steel needs a lot less tool pressure and will cut materials like brass easier if you make small depth of cut/ passes .
Carbide inserts are not really sharp and are technically not cutting but rather more a controlled crumbling.
Therefore carbide inserts need more constant tool pressure / cutting power to give a smooth surface finish and therefore need more infeed per pass to stop squeaking 😀.
I hope it makes sense…
I use special uncoated polished carbide high-rake cutters that are designed for finish machining on aluminium. They are razor sharp and totally unlike the negative-rake carbide inserts used on hard steels, They lose their edge quite rapidly on brass though, and I think this clip might have been with a tired one!
I have to lap them on a diamond wheel to get decent tool life. I do sometimes use HSS, I have a Deckel/Alexander D-bit grinder, but 99% of the time, the finish I get with the good quality high positive uncoated inserts is as good or better than with HSS. I really need higher surface speeds than my old lathe can manage to get the best results on anything under 20 mm diameter.
When I'm using a fresh or re-lapped insert, I can get a really nice chip formation without any of the squealing. I do grind a lot of carbide tooling and D bits for making microwave feedhorns.
The convenience and dimensional repeatability of inserts is very attractive, but yes, I should grind more tools! (or at least keep them lapped)
Ah! From the time I first heard of this thing I understood the concept of backscatter and the concept of "sound can change the properties of an RF circuit" but nobody ever explained how the thing *worked* beyond that. I figured it would have to be FM (but how exactly?) or PM (but wouldn't the effect be ridiculously small when you're talking about μm of movement against cm of wavelength?). The reality is that the soundwave is doing "FM" on the resonator frequency and then the probe is acting like a *slope detector* (sans the actual rectification part, which happens elsewhere) so that what comes out is AM. In normal application, slope detectors are just about the dumbest way of demodulating FM, but sometimes "dumb" is absolutely beautiful.
The movement of the membrane is around 10 nanometres on a gap of 25 micrometres, so about 0.04%, but at 1 GHz, that amount of change would affect the phase of the retransmitted signal slightly, but I couldn't detect any PM. That could just be the capture effect of the strong illuminating signal, which I could null out to -75 dB after many hours, but may have still been much stronger than the reradiated signal. One day I might set up a more robust experiment.
BS
@@williamnot8934 "Back Scatter", I assume!!!
@@MachiningandMicrowaves Shovel,Rubber Boots and Wheelbarrow BS
@@williamnot8934 Ah, THAT variety. Super
Very entertaining and VERY educational! Great research too.
I have to say I really love these types of video.. I love your shop work too, a mix of this and the shop stuff, but minus the AI GF Secretary thing would be amazing..
I should say I've missed a lot of stuff in the last 6 months or so, I got put off by the pretend AI woman thing..
I'm not saying any of this because I feel that my opinion matters in any way, or indeed is a reflection of your audiance, but I kinda think saying "Well done", and "I like this" is more productive.
Thank you for keeping up your efforts, and adapting, to find the balance between what is pleasurable for you to make, and what's pleasurable for the wider world.
AIMEE did get a bit out of hand, but that's my personal demons fighting to make themselves heard. As a narrative device, taking the role of the all-seeing, all-knowing Narrator in classical Greek plays, AIMEE gives me a way to defuse the potential for sounding smug, but also saves me from re-recording on-camera video segments. I recorded a section of this one that I spent hours on, but mispronounced some words. By then I'd moved all of the camera gear and changed lenses etc, and it was 4.30 AM and I was tired, so I just wrote a TTS script and had AIMEE scold me for saying something silly. In the end, I ditched the whole segment though! I've lost a 10 minute piece to camera about the 150 picometre Van de Waals diameter of Nitrogen molecules and their mean free path and mean spacing, with lots of science about the interaction between the membrane and the molecules in the air. I can't find the audio, video or even the text files, yet I can remember clearly doing the initial rough edit of that segment. I might find it again and put it out on Machining and Microwaves Plus if it looks interesting enough to resurrect.
Fascinating Neil. I am only now realising how many hundreds of hours of work you put into this. I guess you didn't sleep much!
When are we getting the "What's on Neil's shelves video"?
Cheers, Fraser MM0EFI
lol "like billy o" :p the phrases u use r hilarious lol iv never heard a lot of them before
Tremendous.
What a dive into the world of passive RF. Absolutely still with you though my field lines and circuits is a little rusty.
My mind boggles at how tight the design was at the limit of available equipment. Just how far we have not come in all this time. Well, with what we know.
Who believes the narrative on the telly after watching this ?
Great work. A credit to society for producing content like this.
That was a great explanation, thanks!
As someone with more technical ability than many and the frustration of NOT always being able to share my knowledge with those who dont quite drok what i am saying..... My hat is off to you good sir! Excellent discussion and clarity! To be truthful i have wondered about the engineering of these devices for some time, i now understand them! Cheers!
This is super good stuff :) What a high quality production. Super in-depth engineering, RF, a lathe, making things. Excellent!
I am trying to improve my skills, I'm working hard on getting animation overlays out of OpenEMS/Paraview 3D field dumps on to video of real objects with a moving camera position. I messed up the audio at one point because I only have one working ear, so didn't know the right channel had disappeared, so headphone users got vertigo! I need to work on my color-grading skills, lighting and macro stacking, and get better at writing tight scripts and making better designs and doing more effective research. Right now I'm in the USA at a microwave radio conference talking to immensely bright engineers, academics and makers, so I have even MORE ideas to add to my growing list of upcoming productions. Thanks so much for watching and commenting, it really inspires me to improve
I really need a Crossover between this and Technology Connections channels. Also even the background seems to fit perfectly.
I had a Kallax and I nicked the idea from VidIQ and three or four other channels before I even knew about Alec's channel. He has better hair and nicer LED lights.
@@MachiningandMicrowaves so I don’t have to lose all my hope, right? Alec is just as awesome as you!
@@MachiningandMicrowaves I’ll ask the same for him. He deserves to know my opinion about all the sinergy you could together.
@@vlaskz Heh heh, Alec is WAAAAY out of my league, he's a Proper RUclipsr!
"...but this margin's too narrow to contain it." haha xD also "threads per banana"
great stuff
I've been waiting for this. Now I realize I'm going to need to listen a few times to get to grips with the dense material! Good stuffs
There are "only" five thousand words in there. Many are duplicates, but there are SO many sentences. Those are the real menace, sentences. 158 words per minute on average. That's faster than my mother could take shorthand, she says, but she's found the "play speed" option to slow me down if I get too fast for her ears. Hi mom!
The fact they did this before computers and with almost no 1ghz radio in existence is amazing. i really hope the engineer that built it has notes somewhere out there
See my previous video for the background, Termen/Theremin was in the US in the late 20s to late 30s and has some patents to his name, but was of course working in a sharashka after being interned on his return to Russia. I guess that somewhere in a hallowed corner of the KGB archives, there's a well-preserved and revered file of NKVD papers with all of the juicy details carefully recorded.
Deep breath Neil...... A 'The Young Ones' reference....?
Great stuff...!
Superinteresting stuff. For me, as an average not physican it is really hardcore to understand the most but he explains it good. 👍
Great video, you made it very easy to hear, which made my understanding much more solid. Wondering if you find working on a lathe as relaxing as i do.
I'm always stressing about chasing micrometres or ten-thousandths when I'm using a metal lathe. My wood lathe is much more relaxing!
WOW.... I was thinking it was gonna be months before you released this one, and it was release in such a short time, and PACKED with amazing info. Thank you so much. I was on the edge of my couch in complete amazement. I have a few questions or thoughts rather...
No. 1 - The guy receiving the signal, must have been highly busy in making adjustments, as the almost but infinity of variables were constantly changing, like people in the room, how many of them in the room, humidity, seasonal change, temp change of the morning to noon to night time and so many other issues that I myself am not even smart enough to think about.
No. 2 - (I will need to ask my father more details and what is allowed to be covered of things my grand father had done in his past days 50 to 90 years ago) But, Brass is a common thing around the world. Brass has many special property's that are beneficial to the wellness of mankind. Please note, this is something I know very little about, hence, I will see what my father remembers from my grandfather. Brass as we know it today, comes in a handful of alloys, all serving a standard ideals in manufacturing and the finished products requirements.
Brass back in the early days, about early 1900's about WW1 and for sure, WW2 ,used to have a SIR name, of YELLOW BRASS, for the alloy of brass we all have grown to know and enjoy for sanitary or anti-bacterial purposes and ease of manufacturing. But back in the day, there was a few other "BRASS'S / BRASSES" out there that were in common alloying manufacture. The second brass alloy was called orange brass and it's alloys served a particular need and had a certain health risk in the manufacturing process and machining aspect of inhalation risk of micronic orange brass / dust particles, which I do not remember the factual numbers but was like 100 times more risky to deal with, as compared to the "NO RISK" to deal with of yellow brass. Then, there is the RED BRASS, which is 100 times more vial then the orange brass.
(Please note, these numbers are not factual, but merely just to example of the pro-rated scale of volatility or risk factory when dealing with each alloy)
The RED BRASS in most common manufacture (back in the day) was used to make the commutator hub, and or brushes in AC & DC motors and slewing rings. RED brass had a fair wear factor, less arcing, fair heat capability and transfer, among many other strange property's. But the one that it was prized for what it had a weirdo resonance frequency and it would change magically is it was being used as a load or passing current through it. Please note, I do not know all the fancy stuff with this alloy. as it was way long before my time. ORANGE and RED BRASS back in the day used to be accessible to anybody in the USA from your local supplier or smelters. But if I remember correctly, it became illegal to own or maybe illegal to manufacture in a professional setting back in the early to mid 70's. Well, me having only just been born in 1976, I wouldn't hear of such a thing until about 1998 or so, when I was reading cover to cover my first Machinery's Hand Book the 5th addition as that is all I could afford. While trying to get up to speed with metallurgy and what makes the world tick. I needed my fathers help with many questions, which he helped me out so much as it was just second nature for him to already just know.
I was in the process of learning about cutting fluids and lubricants, new and old school ways, like pig lard for some of the sticky metals, as strange as that sounds, which is then when I started down the path of which alloys are stickier then others, and is how I seen the various alloys of brass.
Hey dad, what is the difference between the 3 alloys and how are they typically used and why can't I find any at my local supplier, let alone, they have never even heard of that either. My father just laughed and the story time began.
I am sorry for the novel here, but, I can't help but to think, if orange or red brass was used in this type of project all based on some of the story's I was told. The resonance frequency and Q of this toxic man destroying metal alloy, I am betting did play a role in this type of stuff. Maybe perhaps, not this particular unit, but, I sure can't help to wonder now. I would like to learn more about this now.
I use CZ121 brass, but also Naval Brass. It's not good for RF as the bulk resistance is much greater than copper, aluminium, silver of gold, unless you electroplate it with at least six skin depths of silver. A lot of old brasses had arsenic and tin. Red Brass is what I think we call gunmetal (C23000 Copper)? There are some with manganese too, and lead. The difference between brass and bronze is quite blurred as well.
@@MachiningandMicrowaves Oh, arsenic, YIKES... All I could remember was that is was seriously bad for those old school machinist's to mess with it, but were asked to continue for a war effort, which later turned into the "getting the company back on track for civilian production"... pretty crummy. Wow, arsenic.. that is so messed up...Thank you for the info and follow up.
Where has this channel been all my life. This was fantastic content, keep up the good work.
Why YT tossed this video my way, I hoped it would be about this device. What a piece of engineering it is!
Love the ThorLabs goodies box in the back ground
A very useful box with nice contents!
How smart were the people who made these type of devices!!! Hats off to them:)
What else did they make that we don't know about?