I've worked as an industrial electrician, motion controls, 3ph 480, some light rail DC substation rebuilds, some electric arc furnace work at steel foundries, etc. NEVER saw a mercury rectifier until I played Sniper Elite 4. They mesmerized me! I googled them. A video here on RUclips appeared. Photonicinduction was the channel. Well THAT took a turn! So cool to see here a smaller version! Thanks for this!
SE4 is a GREAT game. I remember exactly what mission you're talking about, too. First time o ever saw one was in a video on YT, it was in a battery charger, and to start it you turned a knob on the front that tilts the whole tube to strike the arc in it. It was super cool.
Note the steep rise at the beginning, where the voltage is not enough on each sine wave to turn the tube on, but it jumps to a higher voltage as soon as there is enough voltage.
@@UsagiElectric Interesting property, I wonder if that was ever exploited in the same way SCR and TRIAC is for "dimming" in whatever context it might have been used in Edit: as it seems to be related to filament temp as well
there is a small reverse current that is not seen in the scope. the reverse current will be approx in the ratio of electron mass vs Hg ion mass. The contribution of Hg ion to the total current is rather small (also space charge)
When I used to operate carbon arc film projectors, they were powered by rather large mercury rectifier tubes (many times the size of the two in the video). We were told to keep the rectifier cabinet door closed when they were operating because of the UV light emitted by them.
How many volts were they rectifying for the arc lamps? (If it was over about 15kV, then you'd ALSO get a bit of X-Ray radiation to add to you UV). The glass envelope itself probably blocked a majority of the UV from escaping (but some WILL get out though) Here in NZ, we _USED_ to use MARs (Mercury Arc Rectifiers) for the HVDC submarine link between the two main islands. Unfortunately, they've now been fully converted to Thyristors. You can see a pic or the MARs bank halfway down the page at: en.wikipedia.org/wiki/HVDC_Inter-Island Just imagine getting too close to THOSE puppies when they were active!!! LOL My understanding is that the inter-island HVDC link currently employs two independent 'poles' each operating at 350kV DC at up to 2000A (That should get that slice of toast ready nice and quickly!)
Ran xenon short arc lamps on our 35mms, and you still don't take those power supplies lightly. I can only imagine carbon arc with these tube rectifiers. Always wanted to try my hand at the carbon arc projectors but sadly it's a dying art.
Man, that's awesome! When things get to the high power level, there's some seriously impressive tube equipment out there! As Trevor said the majority of the UV should be blocked by the glass enclosure (especially so on this comparatively tiny little rectifier).
Either your camera or your post-production did a good job filtering out the UV emissions that frequently cause MV rectifiers to appear purple on camera. Such a beautiful, ethereal glow.
This reminds me of the teletype power supply CuriousMarc was working on :) Lovely glow! Thing of beauty, joy for ever, and you've got lots of the other Dave's enthusiasm. And niiiiiiice Tektronix transformer there. Just don't let the usagi-chan tip the tube off and break it, please... I'll have to do some experiments with thyratrons - got two of them somewhere in my lab.
Oh yeah, Marc's TTY power supply was an absolute gorgeous piece of equipment! And the little usagi quickly discovered the tube wasn't going to supply any treats and lost interest, haha.
I have some 2D21 thyratrons here somewhere, as well as some miniature pencil size thyratrons that were used in televisions. I used to have some larger ones that were used for elevator switching I think but I don't know where those have gotten to.....
Ever since I first saw Mercury Arc Rectifiers on PhotonicInduction's channel I have always been fascinated with these components and their construction! Can't wait to watch this too👍
In the 70s there was a rectifier station on my neighborhood. The sign said it was mercury rectifier station for the electric buses (in Brazil they were like trams with a pantograph at the top to the electric line but without tracks). My father worked with mercury rectifiers on radio transmitters: they were HUGE, usually the heating cycle was manual, controlled by push buttons to heat and activate.
The much larger mercury tubes are actually a little different. Those are Mercury Arc Rectifiers, and interestingly, they don't have a filament, making them a cold cathode tube. But the cathode is actually the pool of mercury in the bottom. They're amazing pieces of engineering and I'd love to get my hands on one someday!
Loved this - and the heatsink for the dropper resistor for the filament supply made my day! It's perhaps worth noting that Xenon tubes to not have a "right way up" whereas Mercury Vapour tubes must be mounted vertically (as yours) so that any mercury condensate collects away from the anode when the tube is not in use.
Thank you for the glowing rectifier demo! Love that violet plasma!! If you have a "magic eye" tube in your collection, that could be a good video idea for the near future 👁️🗨️
I'm going to nitpick a little here at the use of the phrase "boil off" to describe the emission of electrons from the cathode. I would call it charged particle emission, since it requires a strong electric field at the surface to pull the electrons out. Also, the "shield" around the cathode is known as a "Wehnelt cylinder". It helps to keep the electric field lines parallel in order to emit an electron beam that doesn't spread out too much and therefore allows the tube to sustain higher currents by counteracting the repulsive force that the electrons exert on one another. As always, thank you for another fantastic video.
Very cool! My grandfather had a battery charger for old cars that had a mercury rectifier. A couple of taps on a transformer, the rectifier and a big old rheostat. Used it in his car repair business back in the days of early cars. Could always tell when it was on by the glow from the tube. :)
There are various gas-filled regulator tubes - the most easily-identified ones are in the "zero" series: 0D3, 0C3, 0A2. There is no cathode heater, hence the 0-volt designation. Also of interest, if you can find one, is the 0A4G cold-cathode triode. There are some very interesting applications suggested for that one in the RCA datasheet. (Such as remote control of line voltage via RF signals transmitted through the line being switched)
I liked these when Curious Marc was working on the TTY... Thanks for the deeper dive.... a nice eerie glow is what I think we all look for in vacuum tubes.... I had an old tape recorder when I was a kid and the tube VU meter was mesmerising.
I didn't realize that the mercury rectifier tubes were capable of such current, that's pretty hip. There's an old substation down the road that used to rectify 600 V for the trolley buses around the city and they used mercury rectifiers, originally at least. Would have been cool to see some 600V 3-phase arc happening.
Hickok tube testers use a #83 full-wave mercury-vapor rectifier (with old-type 4-pin base) because of it's fixed voltage drop at a wide range of current. There was also a short-lived tweed Fender Bassman circuit that used the #83; I've seen the schematic for it but not the actual amp, although I worked on a "transitional" Bassman that had many of the same component value and circuit characteristics as the #83 version, just not the 4-pin socket for the mercury rectifier (it had a factory-stock octal socket for a 5U4). Some folks replace the #83 in a Hickok with solid-state diodes (and perhaps some dropping resistors), but I don't recommend it ---- the calibration and "accuracy" of a Hickok was designed around the #83, and a solid-state rectifier will tend to make marginal tubes read as " good". Note that the Hickok units orient the tube sideways despite the tube manuals saying to use it in vertical orientation only; it is best to allow the tester to warm up for at least 15-20 minutes before testing tubes, to allow the mercury in the #83 to vaporize before pulling B+ current through it (to prevent the #83 from arcing, though this isn't common in a Hickok where the B+ is only 150 volts anyway; that tube will last many years in this application). By the way, an 83-v isn't the same; it's a vacuum rectifier, not a mercury vapor tube.
Just avoid staring too much at them, and protect your skin. Especially for the Hg valve. The nasty UV from them can hurt you fairly quickly if the envelope lets it through.
A large majority of the UV light is blocked by the glass envelope and there shouldn't be nearly enough passing through cause UV burns. Though, protecting your eyes is in general good advice around old electronics!
@@UsagiElectric that’s nice. You would otherwise notice it quite soon after it strikes as you would have an (un-)healthy dose of ozone permeating the area around the valve, and unless you are one of those who cannot sense it, your nose will be an excellent sensor to determine if the envelope is opaque enough to the nasty UV. Cheers
nice look at some old rectifier tubes. I have worked on a old AM broadcast transmitter that had 12 866A tubes . 2 sets of 3 phase. had delay relay to pre heat the 866 before the HV came on. also with the modulation of transmitter the glow would dance around . also 866A give off UV so protect eyes. also some ham radio amps use 866A with 811A tubes. I have one. the Xenon can be used in place. today HV diodes are used. I like old tubes as well . many still made today. 811A, 572/B ,3- 500ZG and Fender still use KT66 and KT 88 on new amps. I like NIXI and VFD tubes. you can make video on 0A2, 0B2 ,0D3 gas voltage regulator tubes. the different gas is different color and a different voltage. also the 6E5 EYE tube and types are neat as well. today I work on 4CW2000A7 tubes 4 in a transmitter water cooled . The ATSC TV transmitter has 2 IOT tubes . Inductive output tubes, lot of tubes still in use today .
very nice mercury vaper tube and xeon tubes i use to worn in broadingcasting and we used an old Gares gy 250 transmitter on am it had i belive the 8008 tube for recitifaction at about 1400 volts and they really glowed nicely under full load.
I have these tubes in a high voltage generator that we use for calibration. I was curious about the glowing coming out of this generator tubes but now I have an idea of what it might be.
Very interesting Video as always. You made me want to get into a new lot of beat up old tubes😅 Careful with the mercury rectifier, that's gonna emit UV. In military and industrial type noble gas filled tubes they sometimes used a radioactive isotope to give the tube that little bit of energy to trigger the ionization. Often that was xenon 80 I think so that should be long gone with its half life of 10 or so years. Without that isotope the gas needs an external source of trigger energy, usually some sort of UV light so in complete darkness such tubes often don't work right
it is actually recommended to pre-heat the Xeon tube before adding HV as well. I love the glow of mercury tubes but it is also feeling a bit risky to use them if they would break open and release all that stuff in the house
Back when 16bit music CDs first became a thing their sound was decried as sterile and lacking warmth, so a lot of people jumped on the tube preamp/amp band wagon. At that time oil caps and transformers made tube circuits ridiculously expensive. Hard core purists stuck with tube rectifiers, but it was a lot cheaper to have/make power supplies made from semiconductors. I'm in the school of if it goes through one tube in the output stage, that's good enough.
Really neat looking! It's like a neon or fluorescent lamp, but it also has useful electrical properties being a diode. Does that Mercury Vapor rectifier give off UV, or does the glass block it?? 👍
These are some wonderful tubes 😊And new merch looks really cool! Is that "machine language" -print a spinoff from some specific episode? (Hope it's ok to ask, not a "full time" follower as one might have already guessed...)
You didn't discuss the development of the high current plasma channel cascade or the breakdown voltage clearly visible on your Oscilloscope at the start of each 1/2 wave. It would be interesting to have a 120V AC supply at 59 or 61 Hz to watch the plasma glow cycle on and off once a second with the out of sync 60 Hz shutter speed. (not sure what your camera shutter speed is and the supply frequency would have to be set for that speed)
just fyi those mercury tubes make UVC light, the very beautiful blue you see is low intensity compared to the amount of UVC light they make. The glass will certainly filter some of it but while it looks beatiful i suggest you don't look at it too long because it can damage the retina, often causing a sand-like feeling in the eye and with long exposure will cause blindness. As i said, the intensity of the blue light is very little compared to how much UVC they put out. UVC fluorescent lights have the same blue glow but it's more visible as they don't have a shield, also they put out way more UVC so they're even more dangerous to look at. All mercury vapor lamps and tubes inevitably make UVC, unless properly filtered they should not be looked at, even though the blue glow they make really is beautiful
Years ago, when i worked in a steelworks using 220volt dc there were rectifier stations parralleled to a ring main for distribution. Each sub had 10 glass mercury rectifiers . We used to check the operation by viewing the rectifier using a welding mask.
love the glow from them tubes :) all i got my self a tube well thort was a vale tube but it was sum thing different sum sort of electrical cut of tube can send pics if your interested ?
Question: How does the half-wave waveform compare to a solid-state device - PN junction and zener compared to tube. Is the cut-off as clean, or is there overshoot?
This was super interesting, thank you for the video! It does make me appreciate the simplicity of using silicon diodes though haha I was wondering, does the plasma just immediately collapse once it hits the zero voltage crossing? Otherwise I could image that the plasma might be retained and continue to be conductive during the negative cycle, right? Also, during the startup of the xenon rectifier at 12:15, it seems to need a higher voltage to start conducting at the beginning, but this starting voltage gradually decreases. It's this due to the gas/filament needing to warm up?
Based on the physics, the plasma will take a non-zero amount of time to revert back to cold gas. I dont think it really makes a difference to the operation. The asymmetric heating is really what allows the electrons to flow
Running what is essentially heater current through a limiting resistor seems a bit strange, but then again why not, it's like 10 watts to dissipate and the load is entirely resistive anyway 🤔
@@wtwarner Resistors always limit current, not voltage. The voltage is not reduced by the resistor itself, but the way the resistor and the load are set up as a voltage divider.
those OC3 and OD3s are voltage stabilizers, not rectifiers, only designed to produce a reference voltage, not pass significant current, although there are much 'beefier' types
Remember a long distance high voltage DC line only has two wires rather than 3 wires like a normal 3 phase high tension line. We have a 800 plus Mile line from the Columbia river in Oregon , near the Washington border, to the LA area in California. 500,000 volts DC then switched back to 3 phase AC in Sylmar. It is actual two way so they can sent power up to us also. en.m.wikipedia.org/wiki/Celilo_Converter_Station
You're absolutely right! But these rectifiers do have a 15V drop across them according to the datasheets, so I would be expecting about 140V to 145V peak on the scope, but in reality, it looked a little closer to 130V to 140V. Could just be my poor reading of the scope though, I really should have dropped the V/cm setting and put 0V at the bottom of the grid and then use the full grid to count the real amplitude.
Back in the mid-80's, I helped an older electronics guru and ham radio operator build a high voltage (3kV) power supply from surplus parts that included a pair of mercury vapor rectifiers. He wouldn't let anyone walk behind the supply while it was operating. It had an open back and his concerns were the UV light and his fear the whole thing would just explode due to the unknown provenance and condition of the parts. Luckily, nothing ever blew up or caught fire, and nobody got electrocuted. The fellow was nearly blind, and he blamed it on his constant playing with those rectifiers since his childhood.
The waveforms of each tube were about the same, but the way they turned on looked a little different. Both have a cliff at the front, indicating it has to pass some threshold to conduct -- makes sense. The mercury (11:00) appears to grow upward. The whole half-wave is present from the start (except the threshold), and the magnitude grows over a few seconds. The xenon (12:16) appears to grow from the back. It starts as the the tail end of the wave, with the cliff near the end. Then the cliff moves forward as the voltage grows. Does anyone have an explanation for this difference? It looked like the scope may have been set to trigger on falling edge for the mercury and rising edge for the xenon. But I haven't used analog scopes enough to understand how triggering works on them, and whether this would explain it.
Very keen eyes! The real reason they look different when powering on is because I'm colossally lazy, haha. With the Mercury tube, I pre-heated the tube for around a minute before applying any high voltage. But, when I switched over to the Xenon tube at 12:16, I was in the groove for filming and didn't want to wait to pre-heat the tube, so I just slapped it together and hit the switch. In the edit, I cut out the approximate 15 seconds it took for the heater to warm up enough to start the ionization process. Having said that, the Xenon tube does tend to have the cliff start at the tail end and move forwards while the mercury tube doesn't. Both tubes do get a full rectification and then grow in amplitude over the next 30 seconds or so after ionization starts. I don't have a good explanation for why the cliff start at the tail end and moves forwards though, that's a really interesting phenomenon that I imagine is related to the different ways that the Xenon and Mercury ionize.
Once upon a time, way way back when, I observed a thyratron in operation. It was part of a DC motor control circuit. It was a phase control circuit, just a bit before semiconductor thyristors or SCRs took over the phase control applications. I mean, there were already small SCRs available, but engineers did not yet know how to really use them. So thyratrons were used as old "familiar and sure working" components. The maximum current was quite limited, but sufficient to drive saturable core amplifiers or "mag-amps". If you find some thyratrons, I believe that would be a nice addition. By the way, a really high current mercury rectifier was called Ignitron and was used in electrochemical applications like galvanic plating. I have never seen one, only read about them in an old book. Another 'by-the-way' item I have used was a short arc lamp in a multi channel oscillograph. The tiny and very bright light could be steered with tiny swinging mirrors onto photo sensitive paper to produce a permanent recording of something before the digital storage oscilloscopes or where Polaroid scope cameras offered too short a snapshot.
mercury arc rectifiers were used when we needed currents of 1000 or 10000A for example for use in electrolysis for metal production (Al, Mg, Na, K etc etc)
Right! They're just gorgeous little tubes when lit up, and while the original designers probably viewed it as an unwanted side effect, to me, it's the primary reason to use them.
it reminded me of some college work I did many years ago we were experimenting with DC machines. The DC rectifier was a mercury vapour tube about 3 foot tall! That was cool. Although that term hadn't been invented. remember the mercury tube does throw off UV light.
I have some NOS 866As (half-wave filament type mercury vapor rectifier), and they come with warning labels in their boxes. "Warning, preheat tube for minimum of 60 minutes at first installation" and, more importantly "CAUTION X-RAYS. This device may produce X-rays when energized. Operation personnel must be protected by appropriate shielding. X-ray warning signs or labels should be permanently attached to equipment directing operating personnel never to operate this device without X-ray shielding in place."
Xrays can only be generated if the anode voltage is high enough, but it has to be at the extreme end of where the 866 is normally operated. at voltages less than 5kv (where the bulk use of 866's were) its safe, at voltages over 10kv, then its wise to shield
@@DanafoxyVixen - There is a good example of this from Glasslinger on RUclips who made an xray tube and was using a 30kv power supply on it and got some astounding xrays out of it. That bastard was hot... Much hotter than the real xray tubes from GE for medical devices. Xrays produced at 15KV are soft but when you get above 20kv and start heading to 30 and 50kv, they get nasty and the frequency of the emissions is much higher and can cause a lot of damage or a burn. This is dangerous stuff.
8:33 - reminds me in a way of the getter on some 30's radio tubes I've seen, they all had this whole reflective layer (I'm guessing it's the getter?) covering the entire top of the bulb with the layer gradually fading over towards the bottom of the tube.
I was thinking the same thing! I just didn't mention it in the video because I guarantee I would ended up confusing myself and saying the wrong words at the wrong times, haha.
You are probably thinking of 01 or 01A directly heated, battery-radio triodes with 4 pin bases.. Some of the earliest ones, even brand new, had a rainbow effect to the getter that did not signify that they were heavily used or about to wear out. Somebody offered me a bunch of them in boxes at a moderate price and I assumed that they were used and didn't buy them. That was a mistake as I could have easily doubled or more than doubled my money on them, but it was early into my days of reselling tubes and there was a lot I did not know. Not to mention, that particular antiques seller tended to be overpriced on most things and drovre a hard bargain, which made me leary.
@@goodun2974 I don't really remember what these were (I'm talking about something I saw some 15 odd years ago when I was a lil' kid), but the 4-pin base does ring a bell to me
I have 3B22s xenon filled on my Colins R-278, yes they produce beautiful colors as well. I think that magic eyes are also very cool and very different in technology from the very beginning to the latest models. It might be a good topic for a future video.
I have several itams with magic eyes in them one a zenith radio an also a old stereo reel to reel deck that records stereo only in one direction as it uses the whole 1/4" tape half for each channel. It has two magic eyes both of those the zenith tombstone radio anfd the tape deck work well. I have not recaped them so it a miracle they are working so good. I dont turn them on much because i do plad on recapping them before they have a problem.
It would be great to look at thyratrons, regulated. To show how it changes during different phases of ignition and various loads, inductive with overload included. But it's hard to simulate.
You know, that is actually something I've wanted to play with for a while. Using phase shifting on the grid of a thyratron to build an adjustable and/or regulated power supply, but you're right, it's pretty tough to get it just right. Plus, the little 2D21 thyratrons I have aren't quite up for power supply duty. Hmm, time to hit eBay for some bigger thyratrons...
@@UsagiElectric i have only heard of it in my middle shool. In the meantime I loved vacuum technology. In the old days I have ridden in electrical grid busses that used it. No way to watch them - closed somewhere in the back. Only stories. It would be beautifully satisfying to watch them work sililarly like in the stories!
Not to go all K___n on you, but how safe is that mercury tube? Could it have been much of a health hazard if it had turned out that there had been sufficient cracks in the glass to allow some mercury to escape?
Guariscimi i tumori e il cancro mi chiamo Biagio di balsamo o Mario somino sono prestigiato con la giocoleria in 19 almeno sono a roccapiemonte a via gargiulo vieni avanti a farmi una siringa e un prelievo di sangue e poi mi guariscimi tutto.
I'm delighted to see this subject on your channel. I remember one time searching online about Tungar rectifiers because I wanted to get myself one... and I found my video I'd made about my own 1910s Tungar charger which I had forgotten I had recorded and also forgotten I even owned. The curse of having too many videos over too many years. hahaha
Te voltage on the transformer is RMS, the scope is displaying the peak voltage assuming 113v, then 113*1.41=159.33V, i'm guessing the 113 is higher due to no load.
I've worked as an industrial electrician, motion controls, 3ph 480, some light rail DC substation rebuilds, some electric arc furnace work at steel foundries, etc. NEVER saw a mercury rectifier until I played Sniper Elite 4. They mesmerized me! I googled them. A video here on RUclips appeared. Photonicinduction was the channel. Well THAT took a turn! So cool to see here a smaller version! Thanks for this!
SE4 is a GREAT game. I remember exactly what mission you're talking about, too. First time o ever saw one was in a video on YT, it was in a battery charger, and to start it you turned a knob on the front that tilts the whole tube to strike the arc in it. It was super cool.
These old tubes are a strong reflection of the creative genius that created these devices !!
I often struggle to wrap my head around these things, but those mad lads invented the things!
Note the steep rise at the beginning, where the voltage is not enough on each sine wave to turn the tube on, but it jumps to a higher voltage as soon as there is enough voltage.
Yup! Takes about 15V to 20V before the ionization occurs and it begins conducting properly.
@@UsagiElectric Interesting property, I wonder if that was ever exploited in the same way SCR and TRIAC is for "dimming" in whatever context it might have been used in
Edit: as it seems to be related to filament temp as well
there is a small reverse current that is not seen in the scope. the reverse current will be approx in the ratio of electron mass vs Hg ion mass. The contribution of Hg ion to the total current is rather small (also space charge)
When I used to operate carbon arc film projectors, they were powered by rather large mercury rectifier tubes (many times the size of the two in the video). We were told to keep the rectifier cabinet door closed when they were operating because of the UV light emitted by them.
How many volts were they rectifying for the arc lamps? (If it was over about 15kV, then you'd ALSO get a bit of X-Ray radiation to add to you UV).
The glass envelope itself probably blocked a majority of the UV from escaping (but some WILL get out though)
Here in NZ, we _USED_ to use MARs (Mercury Arc Rectifiers) for the HVDC submarine link between the two main islands. Unfortunately, they've now been fully converted to Thyristors.
You can see a pic or the MARs bank halfway down the page at:
en.wikipedia.org/wiki/HVDC_Inter-Island
Just imagine getting too close to THOSE puppies when they were active!!! LOL
My understanding is that the inter-island HVDC link currently employs two independent 'poles' each operating at 350kV DC at up to 2000A
(That should get that slice of toast ready nice and quickly!)
Rectron rectifiers? Found another video of these used with a cinema arc projector.
Ran xenon short arc lamps on our 35mms, and you still don't take those power supplies lightly. I can only imagine carbon arc with these tube rectifiers. Always wanted to try my hand at the carbon arc projectors but sadly it's a dying art.
Greetings fellow (former) projectionist
Man, that's awesome! When things get to the high power level, there's some seriously impressive tube equipment out there!
As Trevor said the majority of the UV should be blocked by the glass enclosure (especially so on this comparatively tiny little rectifier).
Either your camera or your post-production did a good job filtering out the UV emissions that frequently cause MV rectifiers to appear purple on camera. Such a beautiful, ethereal glow.
its almost grey right
This reminds me of the teletype power supply CuriousMarc was working on :)
Lovely glow! Thing of beauty, joy for ever, and you've got lots of the other Dave's enthusiasm. And niiiiiiice Tektronix transformer there.
Just don't let the usagi-chan tip the tube off and break it, please...
I'll have to do some experiments with thyratrons - got two of them somewhere in my lab.
I was about to write the same ;)
Oh yeah, Marc's TTY power supply was an absolute gorgeous piece of equipment!
And the little usagi quickly discovered the tube wasn't going to supply any treats and lost interest, haha.
I have some 2D21 thyratrons here somewhere, as well as some miniature pencil size thyratrons that were used in televisions. I used to have some larger ones that were used for elevator switching I think but I don't know where those have gotten to.....
Love valves, thanks for this. Still got my Tektronix 2215 60Meg scope. A reliable companion for many years.
Ever since I first saw Mercury Arc Rectifiers on PhotonicInduction's channel I have always been fascinated with these components and their construction! Can't wait to watch this too👍
In the 70s there was a rectifier station on my neighborhood. The sign said it was mercury rectifier station for the electric buses (in Brazil they were like trams with a pantograph at the top to the electric line but without tracks). My father worked with mercury rectifiers on radio transmitters: they were HUGE, usually the heating cycle was manual, controlled by push buttons to heat and activate.
if you do not have the tracks as the return path, you will need two pantographs and two wires on the top...
@@janami-dharmam Yeah, two "sticks" www.lubus.info/images/stories/technika/siec/3839-153-2011-3.jpg
After second consideration I will start working with tubes. Nostalgia level off the charts here.
Beautiful. I didn't know mercury vapor rectifiers came in such a small package.
The much larger mercury tubes are actually a little different. Those are Mercury Arc Rectifiers, and interestingly, they don't have a filament, making them a cold cathode tube. But the cathode is actually the pool of mercury in the bottom. They're amazing pieces of engineering and I'd love to get my hands on one someday!
@@UsagiElectric i was gonna ask if it was the same principle with the big mercury rectifiers. Question answered.
Loved this - and the heatsink for the dropper resistor for the filament supply made my day!
It's perhaps worth noting that Xenon tubes to not have a "right way up" whereas Mercury Vapour tubes must be mounted vertically (as yours) so that any mercury condensate collects away from the anode when the tube is not in use.
Thank you for the glowing rectifier demo! Love that violet plasma!! If you have a "magic eye" tube in your collection, that could be a good video idea for the near future 👁️🗨️
Looking forward to more videos on particular or unusual tubes.
I still have an old 60s Telerad Vacuum tube radio somewhere that my Dad bought with his first salary!
Stellar demonstration ! Mr. Wizard would have been proud of this .
this is great, glad to have discovered your channel! Great explanation at the beginning.
I'm going to nitpick a little here at the use of the phrase "boil off" to describe the emission of electrons from the cathode. I would call it charged particle emission, since it requires a strong electric field at the surface to pull the electrons out.
Also, the "shield" around the cathode is known as a "Wehnelt cylinder". It helps to keep the electric field lines parallel in order to emit an electron beam that doesn't spread out too much and therefore allows the tube to sustain higher currents by counteracting the repulsive force that the electrons exert on one another.
As always, thank you for another fantastic video.
Very cool! My grandfather had a battery charger for old cars that had a mercury rectifier. A couple of taps on a transformer, the rectifier and a big old rheostat. Used it in his car repair business back in the days of early cars. Could always tell when it was on by the glow from the tube. :)
OD3 Tubes glow good, and you can see the power beam inside.
There are various gas-filled regulator tubes - the most easily-identified ones are in the "zero" series: 0D3, 0C3, 0A2. There is no cathode heater, hence the 0-volt designation. Also of interest, if you can find one, is the 0A4G cold-cathode triode. There are some very interesting applications suggested for that one in the RCA datasheet. (Such as remote control of line voltage via RF signals transmitted through the line being switched)
Reminds me of the argon filled OC3 regulator tube that's in classic Leslie speaker tube amps like the 122.
I liked these when Curious Marc was working on the TTY... Thanks for the deeper dive.... a nice eerie glow is what I think we all look for in vacuum tubes.... I had an old tape recorder when I was a kid and the tube VU meter was mesmerising.
"It's gonna get hot!" now this is a great vid. Mr. C's lab would like it too
The 3B28 was designed to replace the 866A.
You're right, gorgeous colours... I'd love to see a full rectification on the oscilloscope...
I didn't realize that the mercury rectifier tubes were capable of such current, that's pretty hip. There's an old substation down the road that used to rectify 600 V for the trolley buses around the city and they used mercury rectifiers, originally at least. Would have been cool to see some 600V 3-phase arc happening.
Hickok tube testers use a #83 full-wave mercury-vapor rectifier (with old-type 4-pin base) because of it's fixed voltage drop at a wide range of current. There was also a short-lived tweed Fender Bassman circuit that used the #83; I've seen the schematic for it but not the actual amp, although I worked on a "transitional" Bassman that had many of the same component value and circuit characteristics as the #83 version, just not the 4-pin socket for the mercury rectifier (it had a factory-stock octal socket for a 5U4).
Some folks replace the #83 in a Hickok with solid-state diodes (and perhaps some dropping resistors), but I don't recommend it ---- the calibration and "accuracy" of a Hickok was designed around the #83, and a solid-state rectifier will tend to make marginal tubes read as " good". Note that the Hickok units orient the tube sideways despite the tube manuals saying to use it in vertical orientation only; it is best to allow the tester to warm up for at least 15-20 minutes before testing tubes, to allow the mercury in the #83 to vaporize before pulling B+ current through it (to prevent the #83 from arcing, though this isn't common in a Hickok where the B+ is only 150 volts anyway; that tube will last many years in this application). By the way, an 83-v isn't the same; it's a vacuum rectifier, not a mercury vapor tube.
Just avoid staring too much at them, and protect your skin. Especially for the Hg valve. The nasty UV from them can hurt you fairly quickly if the envelope lets it through.
poly carbonate safety specs will help
A large majority of the UV light is blocked by the glass envelope and there shouldn't be nearly enough passing through cause UV burns. Though, protecting your eyes is in general good advice around old electronics!
@@UsagiElectric that’s nice. You would otherwise notice it quite soon after it strikes as you would have an (un-)healthy dose of ozone permeating the area around the valve, and unless you are one of those who cannot sense it, your nose will be an excellent sensor to determine if the envelope is opaque enough to the nasty UV.
Cheers
It'd be cool to see you do a video on voltage regulator tubes like OD3s.
nice look at some old rectifier tubes. I have worked on a old AM broadcast transmitter that had 12 866A tubes . 2 sets of 3 phase. had delay relay to pre heat the 866 before the HV came on. also with the modulation of transmitter the glow would dance around . also 866A give off UV so protect eyes. also some ham radio amps use 866A with 811A tubes. I have one. the Xenon can be used in place. today HV diodes are used. I like old tubes as well . many still made today. 811A, 572/B ,3- 500ZG and Fender still use KT66 and KT 88 on new amps. I like NIXI and VFD tubes. you can make video on 0A2, 0B2 ,0D3 gas voltage regulator tubes. the different gas is different color and a different voltage. also the 6E5 EYE tube and types are neat as well. today I work on 4CW2000A7 tubes 4 in a transmitter water cooled . The ATSC TV transmitter has 2 IOT tubes . Inductive output tubes, lot of tubes still in use today .
very nice mercury vaper tube and xeon tubes i use to worn in broadingcasting and we used an old Gares gy 250 transmitter on am it had i belive the 8008 tube for recitifaction at about 1400 volts and they really glowed nicely under full load.
I have these tubes in a high voltage generator that we use for calibration. I was curious about the glowing coming out of this generator tubes but now I have an idea of what it might be.
Yeah! Now all you need is two big electrolytic caps, a power resistor, and you have your radio's +B.
It is the same process/discharge (with different details) you also see in the TL tubes.
Okay, off topic. I see that can of DeoxIT. Who else hates the way the residual drips out of the straw onto your desk? Drives me nuts.
These were in every telephone to make it ring as the ring is superimposed AC.
Both cool, but aesthetically it is xenon for the win. Good show!
Very interesting Video as always. You made me want to get into a new lot of beat up old tubes😅
Careful with the mercury rectifier, that's gonna emit UV. In military and industrial type noble gas filled tubes they sometimes used a radioactive isotope to give the tube that little bit of energy to trigger the ionization. Often that was xenon 80 I think so that should be long gone with its half life of 10 or so years.
Without that isotope the gas needs an external source of trigger energy, usually some sort of UV light so in complete darkness such tubes often don't work right
The glass envelope blocks virtually all of the UV it generates, I wouldn't worry about it
@@gideonwackers7693 yeah I guess you're right. I highly doubt it's made of quartz glass, didn't think about that
Super cool video!!
it is actually recommended to pre-heat the Xeon tube before adding HV as well. I love the glow of mercury tubes but it is also feeling a bit risky to use them if they would break open and release all that stuff in the house
Well, if you power a radio with that second tube it should play "Highway Star".
Back when 16bit music CDs first became a thing their sound was decried as sterile and lacking warmth, so a lot of people jumped on the tube preamp/amp band wagon. At that time oil caps and transformers made tube circuits ridiculously expensive. Hard core purists stuck with tube rectifiers, but it was a lot cheaper to have/make power supplies made from semiconductors. I'm in the school of if it goes through one tube in the output stage, that's good enough.
the rabbit wasn't interested,,, was looking for full wave rectification.
Really neat looking! It's like a neon or fluorescent lamp, but it also has useful electrical properties being a diode. Does that Mercury Vapor rectifier give off UV, or does the glass block it?? 👍
These are some wonderful tubes 😊And new merch looks really cool! Is that "machine language" -print a spinoff from some specific episode?
(Hope it's ok to ask, not a "full time" follower as one might have already guessed...)
Amazing !
Crazy to see this. I just was watching a train video on how early mercury rectifiers basically killed an early electric locomotive design.
I would like to know what the most complex tubes ( form and function ) you have are.
That was spectacular. Any idea on the temperature reached in the plasma? And the tube itself?
Since they don't have any PN junction, does it mean these type of rectifiers don't drop any voltage?
You didn't discuss the development of the high current plasma channel cascade or the breakdown voltage clearly visible on your Oscilloscope at the start of each 1/2 wave.
It would be interesting to have a 120V AC supply at 59 or 61 Hz to watch the plasma glow cycle on and off once a second with the out of sync 60 Hz shutter speed. (not sure what your camera shutter speed is and the supply frequency would have to be set for that speed)
Something for a future video. - my grandpa's radio had a "magic eye" - how do they work?
Pretty colors.
What's next for the Centurion?
Four terminals.... Is the cathode independent from the heating terminals?
All I can think is how rad these would be in a guitar amp lol
Pair of these in a johnson viking valiant transmitter.
Very amazing great 👍 I like your Chanel
Have you seen Photonicinduction's video where (I think) he starts up some of his?
how do they sound in tube amps?
Does anyone know how fast these are? (Like a schottky diode is faster than a silicon diode)
just fyi those mercury tubes make UVC light, the very beautiful blue you see is low intensity compared to the amount of UVC light they make. The glass will certainly filter some of it but while it looks beatiful i suggest you don't look at it too long because it can damage the retina, often causing a sand-like feeling in the eye and with long exposure will cause blindness. As i said, the intensity of the blue light is very little compared to how much UVC they put out. UVC fluorescent lights have the same blue glow but it's more visible as they don't have a shield, also they put out way more UVC so they're even more dangerous to look at. All mercury vapor lamps and tubes inevitably make UVC, unless properly filtered they should not be looked at, even though the blue glow they make really is beautiful
Years ago, when i worked in a steelworks using 220volt dc there were rectifier stations parralleled to a ring main for distribution. Each sub had 10 glass mercury rectifiers . We used to check the operation by viewing the rectifier using a welding mask.
love the glow from them tubes :) all i got my self a tube well thort was a vale tube but it was sum thing different sum sort of electrical cut of tube can send pics if your interested ?
Would these be considered a "consumable" electronic component, since with each use it seems part of it's function is slowly destroying itself.
yes, all valves/tubes 'wear out' with use, although can last many years
Frankenstein tubes filled with death.
Question: How does the half-wave waveform compare to a solid-state device - PN junction and zener compared to tube. Is the cut-off as clean, or is there overshoot?
This was super interesting, thank you for the video! It does make me appreciate the simplicity of using silicon diodes though haha
I was wondering, does the plasma just immediately collapse once it hits the zero voltage crossing? Otherwise I could image that the plasma might be retained and continue to be conductive during the negative cycle, right?
Also, during the startup of the xenon rectifier at 12:15, it seems to need a higher voltage to start conducting at the beginning, but this starting voltage gradually decreases. It's this due to the gas/filament needing to warm up?
Based on the physics, the plasma will take a non-zero amount of time to revert back to cold gas. I dont think it really makes a difference to the operation. The asymmetric heating is really what allows the electrons to flow
Awesome 😎
Does it have 0.7v drop like a diode ?
Tube rectifiers including gas ones have a quite large voltage drop, >20v
Running what is essentially heater current through a limiting resistor seems a bit strange, but then again why not, it's like 10 watts to dissipate and the load is entirely resistive anyway 🤔
Not really for current limiting. It’s to reduce voltage across the filament.
@@wtwarner Resistors always limit current, not voltage. The voltage is not reduced by the resistor itself, but the way the resistor and the load are set up as a voltage divider.
..I always liked the old OC3s and OD3s ..Darn shame that the current draw is so low with those tubes... Not to mention the voltage drops.
those OC3 and OD3s are voltage stabilizers, not rectifiers, only designed to produce a reference voltage, not pass significant current, although there are much 'beefier' types
@@andygozzo72 I know, but, they DO have a nice glow to them.
I wonder which of the two produces the most X-rays, and at what voltages?
You need tens of kilovolts to produce X-rays. So the answer is, at the voltages used normally with rectifiers, none produces any.
Remember a long distance high voltage DC line only has two wires rather than 3 wires like a normal 3 phase high tension line.
We have a 800 plus Mile line from the Columbia river in Oregon , near the Washington border, to the LA area in California.
500,000 volts DC then switched back to 3 phase AC in Sylmar.
It is actual two way so they can sent power up to us also.
en.m.wikipedia.org/wiki/Celilo_Converter_Station
These are just rectifiers with builtin RGB. Gamer rectifiers!
the rectifier
I'm always amazed by the MARs! Its so fun to see the big ones starting, in example this ones: =YhaQqgXrMMU
Just a reminder, 113VAC (RMS) would be close to 160V peak.
Just a reminder, this type of rectifier have average voltage drop around 15V
@@petrjiricek8039 A shottky mercury vapor rectifier should perform better
You're absolutely right! But these rectifiers do have a 15V drop across them according to the datasheets, so I would be expecting about 140V to 145V peak on the scope, but in reality, it looked a little closer to 130V to 140V. Could just be my poor reading of the scope though, I really should have dropped the V/cm setting and put 0V at the bottom of the grid and then use the full grid to count the real amplitude.
@@UsagiElectric That's assuming the scopes are calibrated. ;)
Back in the mid-80's, I helped an older electronics guru and ham radio operator build a high voltage (3kV) power supply from surplus parts that included a pair of mercury vapor rectifiers. He wouldn't let anyone walk behind the supply while it was operating. It had an open back and his concerns were the UV light and his fear the whole thing would just explode due to the unknown provenance and condition of the parts. Luckily, nothing ever blew up or caught fire, and nobody got electrocuted. The fellow was nearly blind, and he blamed it on his constant playing with those rectifiers since his childhood.
The waveforms of each tube were about the same, but the way they turned on looked a little different. Both have a cliff at the front, indicating it has to pass some threshold to conduct -- makes sense. The mercury (11:00) appears to grow upward. The whole half-wave is present from the start (except the threshold), and the magnitude grows over a few seconds. The xenon (12:16) appears to grow from the back. It starts as the the tail end of the wave, with the cliff near the end. Then the cliff moves forward as the voltage grows.
Does anyone have an explanation for this difference? It looked like the scope may have been set to trigger on falling edge for the mercury and rising edge for the xenon. But I haven't used analog scopes enough to understand how triggering works on them, and whether this would explain it.
the only difference i see in the ‘scope is the sweep period, so i don’t think it’s the triggering
maybe something to do with the thermal stuff?
Very keen eyes!
The real reason they look different when powering on is because I'm colossally lazy, haha.
With the Mercury tube, I pre-heated the tube for around a minute before applying any high voltage. But, when I switched over to the Xenon tube at 12:16, I was in the groove for filming and didn't want to wait to pre-heat the tube, so I just slapped it together and hit the switch. In the edit, I cut out the approximate 15 seconds it took for the heater to warm up enough to start the ionization process.
Having said that, the Xenon tube does tend to have the cliff start at the tail end and move forwards while the mercury tube doesn't. Both tubes do get a full rectification and then grow in amplitude over the next 30 seconds or so after ionization starts. I don't have a good explanation for why the cliff start at the tail end and moves forwards though, that's a really interesting phenomenon that I imagine is related to the different ways that the Xenon and Mercury ionize.
@@UsagiElectric I was wondering about the same thing. Quite interesting to see the different behavior.
the scope triggering was not stable and the display was not rock steady. what you saw is an artifact of the trigger setting, I guess.
Once upon a time, way way back when, I observed a thyratron in operation. It was part of a DC motor control circuit. It was a phase control circuit, just a bit before semiconductor thyristors or SCRs took over the phase control applications. I mean, there were already small SCRs available, but engineers did not yet know how to really use them. So thyratrons were used as old "familiar and sure working" components. The maximum current was quite limited, but sufficient to drive saturable core amplifiers or "mag-amps". If you find some thyratrons, I believe that would be a nice addition. By the way, a really high current mercury rectifier was called Ignitron and was used in electrochemical applications like galvanic plating. I have never seen one, only read about them in an old book. Another 'by-the-way' item I have used was a short arc lamp in a multi channel oscillograph. The tiny and very bright light could be steered with tiny swinging mirrors onto photo sensitive paper to produce a permanent recording of something before the digital storage oscilloscopes or where Polaroid scope cameras offered too short a snapshot.
mercury arc rectifiers were used when we needed currents of 1000 or 10000A for example for use in electrolysis for metal production (Al, Mg, Na, K etc etc)
Also used to rectify current for railway trains, I think one is in use in one of the UK islands.
Those are very cool colours! Lovely blue and purple. Amazing that the colour is a total side effect of the rectifiers doing their actual job.
Right! They're just gorgeous little tubes when lit up, and while the original designers probably viewed it as an unwanted side effect, to me, it's the primary reason to use them.
A good youtuber
Correction a great youtuber
it reminded me of some college work I did many years ago we were experimenting with DC machines. The DC rectifier was a mercury vapour tube about 3 foot tall! That was cool. Although that term hadn't been invented. remember the mercury tube does throw off UV light.
tall tubes were high voltage but relatively low current rectifiers. 3ft rectifiers were common for x-ray tubes etc
Don't know if your familiar with the channel: photonicinduction but he has a huge mercury arc rectifier that's fun to watch.
I have some NOS 866As (half-wave filament type mercury vapor rectifier), and they come with warning labels in their boxes. "Warning, preheat tube for minimum of 60 minutes at first installation" and, more importantly "CAUTION X-RAYS. This device may produce X-rays when energized. Operation personnel must be protected by appropriate shielding. X-ray warning signs or labels should be permanently attached to equipment directing operating personnel never to operate this device without X-ray shielding in place."
i got some of them too i plan to put them to use at some point just got a few others projects to finish first
Xrays can only be generated if the anode voltage is high enough, but it has to be at the extreme end of where the 866 is normally operated. at voltages less than 5kv (where the bulk use of 866's were) its safe, at voltages over 10kv, then its wise to shield
@@DanafoxyVixen good to know. It does say "may produce" not "will produce" after all.
@@DanafoxyVixen - There is a good example of this from Glasslinger on RUclips who made an xray tube and was using a 30kv power supply on it and got some astounding xrays out of it. That bastard was hot... Much hotter than the real xray tubes from GE for medical devices. Xrays produced at 15KV are soft but when you get above 20kv and start heading to 30 and 50kv, they get nasty and the frequency of the emissions is much higher and can cause a lot of damage or a burn. This is dangerous stuff.
my tube friend is the 12Ax7
0:28 - do you have a video explaining why the 6AU6 is your favorite?
He built an entire vacuum tube computer out of them. Check out the videos...
8:33 - reminds me in a way of the getter on some 30's radio tubes I've seen, they all had this whole reflective layer (I'm guessing it's the getter?) covering the entire top of the bulb with the layer gradually fading over towards the bottom of the tube.
You're right. The getter flash after the tube is evacuated.
I was thinking the same thing! I just didn't mention it in the video because I guarantee I would ended up confusing myself and saying the wrong words at the wrong times, haha.
You are probably thinking of 01 or 01A directly heated, battery-radio triodes with 4 pin bases.. Some of the earliest ones, even brand new, had a rainbow effect to the getter that did not signify that they were heavily used or about to wear out. Somebody offered me a bunch of them in boxes at a moderate price and I assumed that they were used and didn't buy them. That was a mistake as I could have easily doubled or more than doubled my money on them, but it was early into my days of reselling tubes and there was a lot I did not know. Not to mention, that particular antiques seller tended to be overpriced on most things and drovre a hard bargain, which made me leary.
@@goodun2974 I don't really remember what these were (I'm talking about something I saw some 15 odd years ago when I was a lil' kid), but the 4-pin base does ring a bell to me
Beautiful LEDs :D
I have 3B22s xenon filled on my Colins R-278, yes they produce beautiful colors as well. I think that magic eyes are also very cool and very different in technology from the very beginning to the latest models. It might be a good topic for a future video.
I have several itams with magic eyes in them one a zenith radio an also a old stereo reel to reel deck that records stereo only in one direction as it uses the whole 1/4" tape half for each channel. It has two magic eyes both of those the zenith tombstone radio anfd the tape deck work well. I have not recaped them so it a miracle they are working so good. I dont turn them on much because i do plad on recapping them before they have a problem.
Can you make a full bridge rectifier with these?
Yes, but you need at least 3 separate filament transformer windings.
It would be great to look at thyratrons, regulated. To show how it changes during different phases of ignition and various loads, inductive with overload included. But it's hard to simulate.
You know, that is actually something I've wanted to play with for a while. Using phase shifting on the grid of a thyratron to build an adjustable and/or regulated power supply, but you're right, it's pretty tough to get it just right. Plus, the little 2D21 thyratrons I have aren't quite up for power supply duty. Hmm, time to hit eBay for some bigger thyratrons...
@@UsagiElectric i have only heard of it in my middle shool. In the meantime I loved vacuum technology. In the old days I have ridden in electrical grid busses that used it. No way to watch them - closed somewhere in the back. Only stories. It would be beautifully satisfying to watch them work sililarly like in the stories!
Not to go all K___n on you, but how safe is that mercury tube? Could it have been much of a health hazard if it had turned out that there had been sufficient cracks in the glass to allow some mercury to escape?
Great photography.
You could use both of them to make a very pretty full wave rectifier. :)
Thank you!
I actually did think about this, but I didn't have enough alligator clips, haha.
@@UsagiElectric LOL.
As an autistic person I find radio tubes just so fascinating.
I love the old VT127A and the 327A. They both have the uranium glass pin pass throughs! Great video.
Thanks for sharing, looks cool indeed. If you'll rectify the AM signal, will the plasma be blinking in sync with music? :)
Yes. Totally. I saw that on photonicunductions channel
Always fun to do !...cheers.
Guariscimi i tumori e il cancro mi chiamo Biagio di balsamo o Mario somino sono prestigiato con la giocoleria in 19 almeno sono a roccapiemonte a via gargiulo vieni avanti a farmi una siringa e un prelievo di sangue e poi mi guariscimi tutto.
What a surprise I was just working with some Mercury Arc lamps for water disinfection
I'm delighted to see this subject on your channel.
I remember one time searching online about Tungar rectifiers because I wanted to get myself one... and I found my video I'd made about my own 1910s Tungar charger which I had forgotten I had recorded and also forgotten I even owned. The curse of having too many videos over too many years. hahaha
Te voltage on the transformer is RMS, the scope is displaying the peak voltage
assuming 113v, then 113*1.41=159.33V, i'm guessing the 113 is higher due to no load.