I thought this was going to be a fake kinetic switch
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- Опубликовано: 14 окт 2024
- When I bought this it seemed so much smaller and cheaper than the other kinetic switches (self powering remote control switches) that I thought it would probably just have a battery inside.
It didn't help that when it arrived it felt exactly like a cheap clicky tactile switch. But it turns out there's a reason for that.
This is the first piezo powered remote switch I've seen, and the circuitry is very odd in the way it resets itself. One of the worst things for microcontroller stability is a slow voltage drop. It can cause problems with software register corruption without causing a full reset. This circuit gets round this in a bizarre way.
The range on this switch is acceptable if used in line of sight of the receiver or direct sight into the room the receiver is in. But it's not putting out a strong signal. Normal receivers do not pair with this switch, and its receiver does not pair with other remotes. For maximum range and versatility I still recommend getting a standard battery operated remote.
The piezo disk is supported by a rim so that it bows slightly when the button presses against it.
If you enjoy these videos you can help support the channel with a dollar for coffee, cookies and random gadgets for disassembly at:-
www.bigclive.co...
This also keeps the channel independent of RUclips's advertising algorithms allowing it to be a bit more dangerous and naughty.
The secret to being pleasantly surprised is to be a constantly jaded cynic. Works like a charm.
My philosophy entirely. Such pleasure is not often though.
Cynicism is cancer to self and to society.
@@jonathansmythe6273 Pessimistic (and cynic)people sure live a happier life than optimists.
Because either they are right or pleaseantly surprised. 🤗
Most people make an online purchase thinking "I'm getting something legitimate." Get something counterfeit.
BigClive orders something online thinking "I'm going to get a fake product." Gets something legitimate that exceeds expectations.
It's reverse psychology!
I think you meant: "Gets something legitimate and is disappointed." 😁
Weak pulse
Ah, Clive roots round the bins of Ebay, the same way those sellers root round the bins of Chinese factories for stuff that looks like it might sell. Or, I was gonna say, stuff that failed quality control testing, but then I remembered it was China and had a little chuckle.
If he ever wants to go full kamikaze, sign up to Wish.c0m, Clive. Not putting a proper link in, don't wanna improve their standing.
Actually... what about a showdown? 5 items each, from the dregs of Ebay, and the pride of Wish. So it's a fair fight! See which are truly the worst.
@@greenaum I like the Ashens segments where he buys random crap from Wish, some of the results are wild.
Seller: Excellent! Big Clive just bought one, now we can raise the price and profit from his subscribers.
That actually had me wondering if clive has an "anonymous" ebay account for buying stuff.
too late, we need to get the skinny on the topic of his next video in advance, so we can buy _before_ the video drops. ;D
Clive I must know we're did you get that nifty screwdriver I'd like to add one to my tool arsenal
I always thought it was Big C Live all these years... man i’m stupid
@@matthicks1545 until I heard his name was clive, I thought that too
We had strain gauges in aviation with piezoelectric crystals in them for Vibration analysis. it was a metal block with three axis , one crystal per axis, the electric current was sent to the computer that mapped the voltages into IPS, or inches per second. Each rotating component had its own signature, so you were able to find out if there was a bad bearing or gear somewhere in the machine. They were also used for rotor balancing, adding weight to the rotor in the correct clock position would correct lateral balance issues and pitch link adjustment for vertical.
Truly amazing engineering. That someone figured it out. There was a problem and design something to fix it
Oh that's really cool! The uni i go to is doing lots of work with machine learning and vibration analysis from things like that, from wind turbines to detect likely failures it's super interesting
Interesting, I spent several years writing the software for that kind of analysis but never used a tri-axis sensor. We mostly just used two sensors for two axis.
That sounds like a fairly common accelerometer design
I find it amazing that such a minute bit of kinetic energy can do this. In fact the whole EMR scenario is basically magic.
One of the reasons I enjoy working in electronics is the colourful components and cables. But SMD has 'monochromed' everything; either black or brown. Thanks to BigClive for bringing some colour back into it with those red, blue and yellow coded marks on the PCB photo!! :-D
Bro I feel you. My greatest joy is opening electronics that had hand assembles circuits and pcbs from products 25 years old
I just got done fixing up the Vox organ from 1967 in my profile pic. The thing's an absolute work of art under the hood.
@@kirk5452 From the mid-late 90's? (1996 was 25 years ago) I'd say the majority of electronic products were starting to be made with SMDs by then. You're probably thinking of products made in the late 80's and early 90's.
@@thegorgon7063 the mid 80s were clearly 25 years ago and you can’t convince me different.
@@JasperJanssen lol 😂 when people say "10 years ago" I _still_ think of 1990...
Big Clive's house must have a more eclectic collection of light switches, LED lamps, USB chargers, etc than any other house on the planet
Probably lives above a poundland store and has a hole in the floor.
A real eclectic electric collection/
don't forget string lights
Don't forget wuffers of all sizes colors.
What's it like at Christmas?
Thanks for scope view on this one!
The filter circuit going to the antenna is a balun. It is used to provide impedance matching between the PA stage of the RF transmitter and the antenna. The PA stage might for example be designed for a 90 ohm load, but the antenna, might be 85 ohms. The antenna which is a PCB stripline is tuned to a specific frequency or a frequency band. Changing the C and R's in the balun changes the impedance matching and also the Q of the circuit. At RF you cannot just add a resistor in between to match load, you need to use a combination of C and R's to get the correct match. The balun is also used to round the square wave output from the transmitter into something more sine. You want the energy to be directed to the antenna and for the energy to be at the desired frequency like 488.0000MHz and not contain any harmonics, else you'll be radiating the harmonics, which is 1. a waste of power, 2. means you'll fail on your RF emissions. The choke (inductor) on the balun is used to bias the PA of the transmitter and also stop back reflections. You want the signal from the PA to go the the antenna and not onto the power supply line, which without the choke would also look like an antenna.
The RF chip is essentially a HF mixer. Not sure if the output is FSK or simple pulse modulation. The 26MHz xtal will be used as the reference for a PLL. The PLL will probably generate a 488MHz output for the UK market. Internal to the Rf chip will be some filtering to round the edges from the PLL. The RF signal is them modulated by the signal from the micro, either by a switch or VCO.
The transistor used to shunt the power to ground is required to stop the micro and RF chip going into brownout when the supply starts to drop. It is also used to restart the firmware and make sure that you always go into a fail safe mode of operation. You don't want the micro to sit around brownout especially if the user clicks the button in quick succession as the power rail with then will rise and the micro might not boot correctly causing it to go into nar nar land. Think of it like a hard reset, when your TV remote goes wrong and you cannot get it to turn the TV back on what do you do. you pull the batteries out thinking they must be dead. Maybe you replace them, but if you don't and put them back in the remote will probably work again. This is where the batteries are reaching end of life and the internal resistance is high. Pulling them out and putting them back in again does 2 things it resets the micro in the TV remote and 2 it scrapes the electrodes on the battery giving you a few more days out the batteries as the electrodes have been scraped reducing the resistance.
Finally, RF transmitters like a nice stable power supply. Getting the micro or the RF chip to operate at Vin min or below could cause latchup. Latchup is bad, causes things inside the silicon to go pop!
The piezo was probably a dual disc, or split disk. Designed to give you a positive and negative pulse on each push / release of the button. -Cost or lack of power may have caused the designer to stick with the simple design they have implemented.
Every time you click that button I get a sudden craving for Snapple.
Glad to see I'm not the only one that presses the lid up and down lol
Micro-controllers usually have under-voltage lock-out to prevent low voltage from causing unknown states. Since the micro-controller relies on its supply voltage rising above UVLO to detect a button press, the self-shunt is there simply to make sure the UVLO kicks in again at the end of sequence to setup the next press.
Makes sense that the receiver will be the one with the timer, since timers require a constant current to run and the transmitter is built to basically hold no charge beyond what is needed to send a signal.
that is actually quite clever and elaborate
My views of Chinese goods are slowly changing. This and the DC clamp meters are 👍.
I just found this channel, and read some comments and it gave me hope in humanity again. What an awesome little community of intelligent people
Between this and the magnetically operated switch I'm surprised by the components that can work reliably with brief and this tiny burst of power.
Ultra low power electronics are freaking cool. They open up a lot of applications people still haven't really thought of. Sensor networks are the ones I most interested in, but there's doubtlessly good ideas I've never imagined.
@@travcollier seeing this more and more in modern building automation. Solar powered RF thermostats or kinetic light switches...
I have had a kinetic switch doorbell for about 5 years now. It has been FAR more reliable than battery versions that would crap out without notice - as well as being severe weather resistant. I did have to be creative where the receiver was (to ensure reliable reception) but it has been consistent. The switch is outside a brick garage with metal doors and the receiver is in the basement inside the HVAC service room. I'm not sure if mine is piezoelectric - but the switch toggle travel seems to be "forced" and may be the magnetic model design.
Not reliable i fear...theyll be turning off things at random unless theyre coded properly.
I can't wait for Clive to smash quartz rocks with a hammer and measure the potential across them
Banging together quartz pebbles in the dark is fun (?) - they glow briefly through the entire body of the white pebble.
I don't know if it's accurate, but I remember reading that a Piezo crystal like this is how those Nike plus pedometers that worked with ipod back in the day worked. Each step triggered a crystal to transmit a step.
I’ve got one somewhere. I’ll try digging it out
I found the ipod dongle end - maybe the shoe bit is in the landfill with a smelly pair of shoes
I can totally see the advantage of this for short range operation in the same room as the light. It's one thing to change the battery in a hand-held remote, quite different to have to change it in the switch by the door - perhaps stopping you from turning it off !
But what would be really good is to use this for adjacent switches, wall-switch replacements, and to have a battery powered remote that sends the same signal more powerfully so you can override it from anywhere. If the radio signals aren't compatible, that just points to a need to reverse-engineer the protocol and transmit it from a special remote control.
I have a bunch of ancient X-10 Stuff in my house. I have a good dozen stick-on wall switches that will control 3 different channels as well as a dimming function. In the last 25 years I've had one switch break and be replaced, and had to change the battery once in one other switch. All the rest are still working on 25 year old CR2035 batteries, and not giving any problems.
Now, some other switches may not last anywhere near that long. But batteries dying may only be a problem for 25th century archaeologists trying to turn on the lights in a house they are excavating.
There are high-voltage piezo devices used as ignition for gas barbecue grills and even propane torches. Those put out several thousand volts. Old phonograph cartridges using piezo crystals used to be fairly common, as did so-called "crystal microphones"; the latter were common because they were inexpensive and put out a very high signal level.
I wonder how much of an RF range one could get from using a button with a a 'piezo igniter'?
I have a fond memory of crystal earphones for their sensitivity in making minute signals audible.
@@w-mwijnja8919 Well, without getting into active devices, a simple spark-gap with tuned circuit and a decent antenna might make an interesting experiment.
Indeed, a crystal phonograph cartridge could easily put out a Volt.
@@fivish One of the electronics stores I used to spend some time in when I was a kid had them in 1, 2, and 3 volt versions.
The placement of the vias does not affect RF until they are far enough apart to let RF through. That would be tens of centimeters for 433MHz.
The placement of the vias would be down to a PCB designer only wanting to put the minimum in and the RF designer wanting the board looking like it has been blasted with a shotgun (the vias are clustered around the output matching circuit although an attempt is made to put plenty in around the power section but components restrict them there).
I work with RF and power engineers who insist on ludicrous numbers of vias (particularly laser micro vias) to the point that rework on PCBs can be a real challenge because the heat wicks away like the lamp boards on aluminium you tear down.
The trouble is that the PCB design software allows engineers to zoom in to a scale where they can always see room for another via, so they will insist on it.
Also, the output network to the antenna serves two purposes: one is to filter out any frequencies that must not be emitted, and the other matches the impedance of the signal to air (usually 50 ohms) for optimal energy transfer to the 'aether'.
This also explains why they went to the expense of putting a crystal in because it is multiplied to the RF frequency - yes 26MHz doesn't multiply directly to 433MHz, but it is a common crystal frequency in RF and so the PLLS structures already exist). The crystal has good accuracy and drift characteristics so that the output will be on target.
@@OntologicalQuandry Hadn't thought of impedance matching, but it could. I agree, it's probably a filter to strip out harmonics.
Very interesting!
Many years ago I built a seismometer using a piezo disc for the sensor. I fed the signal from the disc into an op amp integrator. There was zero travel of the seismic mass and the response was totally set by electronic components. It wasn't practical though because the disc was easily destroyed by bumping the case..
Clive, I get excited every time you pull out a 'scope, even if it's just a toy one. A picture is indeed worth 1000 words.
Yay for scopes! Wish he marked the point he was probing on the schematic though.
what scope is that
@@Akio4800 That's a DSO Nano from Seeed Studio
Seems better than the cheapy ali express kit scope
@@TheErador Probably 100x better, but real scopes are not much more expensive.
These are very interesting switches. Saves running wires as well as saves the need of batteries. Very efficient which is kind of weird in this throw away society we live in.
Pretty sure what you described with the “curie temperature” was how electrets are manufactured. Piezoelectricity is different. A crystal is chosen with a particular geometry such that when squeezed out of its equilibrium position there’s more positive charges on one side than the other, and sliced (or grown) in a particular direction to maximise that. An electret moving between capacitor plates will also produce a momentary voltage, much like moving the dielectric within a standard capacitor with some bias voltage across it.
Edit: a video about making electrets:
ruclips.net/video/1DR-tTU8uIM/видео.html
No, he's exactly correct. BigClive is describing a process called poling, which is necessary for most common piezo materials like lead zirconium titanite (PZT). The process aligns the electric dipole moments in a crystal, otherwise they are naturally randomly oriented and tend to cancel each other out. The only thing is you want to have an elevated temperature, but below the Curie temperature. At the Curie point, the electric polarization is lost.
ruclips.net/video/k6Cu1KTqVjM/видео.html
en.wikipedia.org/wiki/Piezoelectricity#Mechanism
@@straightpipediesel
Oh I see, that would make it much cheaper than growing a single crystal.
As far as I'm aware even single crystal piezos (as opposed to the typical pzt ceramics) have a Curie temperature at which point polarization is lost. Also, heating until Curie temperature is not required to pole piezos, it's just easier at elevated temperatures.
Such a smart energy harvesting application. I love the idea of self powered sensors.
I like the one with the battery also. Many years ago, when my good wife and I switched from a pull type RV to a motor home, the first Class A we purchased had a rear view camera but it only showed, perhaps 4 feet behind the 36 foot rig. So I picked up one of those cheap backup camera for cars and installed it in the back bumper of the rig. The device was intended to be powered from the back-up lights but I wanted it to come on when I was traveling down the nations highways. So I picked up one of those little battery powered remotes. Mine came with a key chain dongle that had two buttons. I wired it in to the main 12 volt circuit and used the little button to turn the color camera on and off as I needed it. The device served me very well for the 20,000 miles I put on the old rig before I traded her off. On the trade, I kept the setup but since my new rig had a decent camera and display on it, I never installed it on anything. I am now considering sticking it in my Ford car just for shits and giggles. I love gadgets so that little display could join my car camera, fuzbuster and GPS since my car is old enough that it comes without these luxuries.
I have encountered some of those piezo devices in drum machines for one example. I also have salvaged some, where they were presumably intended to be sounders of one sort or another (in telephones). I took one that was encased in blue plastic and just for the heck of it connected it to my scope, and it seemed to make a pretty good microphone! I also recall running across something a while back that talked about using one as a "pickup" in a guitar...
Piezo crystals generating electricity by walking are also used in kids' trainers that light up as you walk.
I never actually thought I knew every kind of transmitter receiver circuit that existed, but I never imagined that this kind of thing did.
The micro transmits when it comes out of power-on reset - a register is set when this happens to let the software know. The transistor is used to quickly short the 5V supply after sending the data, ensuring that on the next switch press, the micro will again come out of reset and transmit again. It doesn't care about rising and falling voltages - that's what power-on reset circuits do anyway. Great circuit.
That's a brilliant little device for the money!
Un-fun fact:
The rounded triangular metal dome switch upper section also appeared in some Atari joysticks (2600 models mostly), Amstrad and Sinclair and Commodore joysticks and various Quickshot, Cheetah, Zipstick and the like! It's weird how certain components no matter how small manage to live on in something else years after they were first used!
I use piezo on my DIY timegrapher for watches. It can sense those tiny ticking sounds and software on PC calculates how many seconds the watch is fast or slow in 24 hours or 86400 seconds.
Piezos are used in cars too, probably the most important one is knocking sensor. It's piezo, senses knocking and in matter of milliseconds tells the ECU that we got a problem here in cylinder number 3
But that switch you got, just wow
These Piezo triggers are great technology. When we moved in, the FIL got rid of the old doorbell system, because it was somewhat broken or whatever. Instead of getting a good new one, we got one of those wireless things, with a bigger bell thing and a small battery powered transmitter at the door. Batteries need for the button and batteries needed for the bell. And it was just that always when someone came to deliver something or whatever, it didn't work because the batteries were empty. Then I found a system that could be just plugged into the wall and had a button with Piezo power. And ever since, no problems. This thing works like a charm and no more worrying about batteries. I didn't particularly test out range or how many walls it could overcome, but at least it works from outside the door through one wall for a few meters and didn't have any problems with that.
It's an interesting device, it is indeed ' neat ' that once it's finished sending the packet it discharges the reservoir caps ready to repeat the process and also nice to see this on your little hand held ( no smut intended ) ...cheers.
Thank you Clive. Now replace the Piezo with a battery and see if you get better range out of it or if it stays the same. I guess you might have to make capacitor dump circuit for the battery so it does not get shorted out when the circuit clamps down the supply rail.
Probably won't. Spamming the button seemed to get the caps fully charged pretty easily.
I think you need to adjust the transmitter itself to draw higher power. (Which makes me think that some way to adjust that would be a nice feature for these sorts of things.)
@@travcollier yes I think your right.
@@Robothut It is sort of cool that spamming the button likely makes it work slightly better though. I mean, that's what we all do anyway when it doesn't work the first time :)
@@travcollier So maybe remove the power dump transistor and just let the unit send the commands as long as the battery ON button is pushed, maybe that would spam "send the code over and over until the receiver sees it. But in the end I think your right the transmitter is just so low power to work in this fantastic design that range was just not what they were going for.
@@Robothut How good would a switch like this one be if the user had shaking hands?
This is the best reversice engineering of a PCB I've ever seen on YT.
Does it almost on the daily
Unrelated but my always on outside light (CFL) died last week, just in time for one of your videos about de-rating led bulbs. So now I have a big clive-ified outside light that draws basically no power. Thankyou :)
the piezo elements are used
1. as tweeters in cheap stereos in the 80s
2. ringers in cheap telephones especially the one promoted by the purina ralston chex cereals in the 80s.
3. electronic musical and recordable greeting cards.
4. electronic drum sets plastic frisbee shaped or even wedge shaped pads has piezo elements that when you tapped them they sent a signal to the controller and it played a synthesized drum sound.
Interesting little circuit. Thanks!
I was amused by the ad that popped up for this video - one of those "detoxifying" metal rust footbaths.
FULL BRIDGE RECTIFIERRRR, I can not hear the name bridge rectifier without ElectroBooms unibrow coming to mind.
Or AvE calling it a rectumfrier.
I bought a piezo disc for the purpose of building a custom synth drum. Connected it to a drum module which acted as a MIDI controller, which was fed to my laptop to trigger samples. Worked fantastic..
We had some fun in school recording sound using piezo discs as contact microphones
I don’t pretend to understand any of this, but for a ‘button’, I thought it was a lot of components!
All very clever.
The fact that you can get the transmitter AND receiver for 12 Pounds is itself pretty amazing good value! There are many useful applications for this, where the relatively short range is irrelevant. Swimming pool gate alarm comes to mind as a very useful application.
The color coding pictures is brilliant, so easy to follow. great idea!
As someone who is basically electronically illiterate I appreciate the color coding, thank you
you mentioning the piezo electric walkways reminded me, back in high school I actually did a project that ended up including looking into the company that was doing the whole power from footsteps thing, even going to one of the installations they had done for their second generation version. at least the 2nd gen ones were just using gearing to turn the stroke of the panel being pushed down into rotation for a dynamo. they put out way less power than the company was claiming, as far as I could figure out including less than the fancy display setup that came with them was saying. got to talk with the person who organized the local side of the installation, apparently the company was a nightmare to work with, and basically went radio silence once the initial pr stuff was over
I was expecting a lighter mechanism inside.
I've noted before that the mechanism inside an electronic lighter is seemingly purposely designed to accept a key cap.
Ive contemplated using the clicky lid from a fish paste or baby food jar as an acoustic button.
Using the larger diameter piezoelectric transducer and a short, stiff compression spring, possibly from the aforementioned lighter, could possibly provide more energy and extend the range.
Careful design of the enclosure could even provide IP67 weatherproofing for a button at the garden gate.
One day I may get off my lazy backside and actually try my ideas out.
The snap dome might purely be there for the tactile feedback. Just deforming the piezo should generate enough power, probably enough to briefly light a white LED...
You can make a TV clicker out of it...just like the 1950's
i thought those were ultrasonic tuning forks...
Actually just an aluminum rod. Pressing the button cocked and released a striker, releasing the button clamped on the rod to damp vibration. Truly genius!
Nope. Those were not electromagnetic devices. I still have one from Sony. Two tuning fork like rods that ring in the audible range. My high school girlfriend’s silver bracelets would change the channel too.
Back to no batteries in the remote would be great!
@@johndii2194 only if you want to go back to extremely limited functionality. The old manual ultrasonic controls only allowed channel and on/off control; the high end ones did volume up/down too, but that's about the limit of what's possible!
I did repairs for a Curtis Mathis shop and theirs only operated the channel selector. Push the button on the remote and a motor turned the channels selector. When it got to the one you wanted you release the button. Channel Zero turned power off!
I work as a product engineer in a factory that makes piezoelectric components. The 'crystals' are ceramic materials which become piezoelectric when DC voltage is passed across them at temperature. Voltage is typically 2-3.5 kV per mm and temperatures are typically around 100-130°C which is usually a bit below the curie point of most of the materials. This process is usually done with the components submerged in heated insulating oil to prevent voltage breakdown, but can be done in air if the components are thin enough. If you heat a piezoelectric material to above its curie point it ceases to become piezoelectric, but the mechanism is reversible
I used already (2 different) RF relais (also 433MHz) with the small remotes with 2 buttons on it and they also had those small coiled antennas. They had a rather small range of like 5 meters. Then because the range for a garage opener was too small (knowing nothing about antennas), I desparately uncoiled the antenna and wow: the range was at least 3-4 times better.
That was great with the oscilloscope signals. I wonder how many presses before it fails? I would imagine quite a few.
Thanks clive, loving the pink screwdriver.
fnarr fnarr
The zener makes sense, as the output of a piezo unit can well exceed 5 volts. The clamp makes sense as well, keeping the controller VCC outside of the indeterminate level, which could reset its code, send multiple toggling signals and more.
Overall, it's elegant in its simplicity.
The little RF transmitting IC is probably the CMT2119AW, the marking starts with 9A and the pinout matches.
I really missed not seeing the voltage rail on a scope with the first kinetic switches .. awesome addition ❤️
Thanks, Clive. Your videos are fascinating and informative of what's out there in the market place.
I recall, in the late 90’s, there was a manufacturer that was putting piezoelectric units in the soles of track shoes so you could charge while you ran. Since they are no longer around I’m guessing they were crap or they missed a fatal flaw, or both.
Yeah, it was just marketing fluff.
However, a modern development is flashing LEDs in trainers driven by similar piezo, so it's useful as a safety thing in the dark. Low duty cycle makes them viable - quick pulse of current to flash the LED every step. They were in fashion 3 or 4 years ago (*) but no serious running shoes seem to have them. Night runners seem to prefer elbow-LEDs similar to flashing cycle lights.
* search YT for "shuffle dance" videos in 2017 or 2018 and you'll probably see a few in use, though the nes with more LEDs have batteries and just use the piezo cell as a trigger
At least the child shoes have nothing more than a button cell and a led, the connection is only created through the impact vibration.
@@gordslater man, flashing lights in shoes was all the rage in 2002. At least, as a kid. But it would only last a month or two because of the battery. One kid in my school had one last 4 months and kept boasting about it until it finally died. Generating its own power sounds much better!
@@kaitlyn__L I never had any back when they were a thing in the early 'oughts, didn't realise they were battery driven, always assumed it was some kind of dynamo/kinetic energy deal.
@@TheErador oh, yeah! There of course was something to detect when you were taking steps (maybe piezoelectric, maybe quartz, maybe an accelerometer), but it wasn’t enough to run them from. I never had any, but a bunch of my classmates did.
I was surprised it generated enough current to run all that .
Yeah, cool to see, especially on the scope.
How long will it last tho?
@@TheNamesArif I’m no expert but I am pretty sure that most quartz crystals will outlast any human life. I am pretty sure there are plenty vintage electronics with an quartz Crystal inside them for syncing that still work.
Take a look at Quinetic. Just used them in my garden. Brilliant.
I'm totally amazed the micro amps from the piezo transducer can run the cpu and rf to bleep the data code. Super efficient design!!!
Back in '95 I was working for a security electronics firm that had a stainless-steel external alarm siren box in their product range. These boxes have front and back tamper switches but I had a play with epoxying a piezo disc to the cover to see if an attack could be detected well before the box was levered off the wall. Worked very well but there was zero interest from the company management. I've still got the cover here somewhere.
Your videos make me want to actually get into electrical engineering. Maybe I'll actually work on a project this weekend. Thanks for the informative videos!
Big Clive-Inventor of the Joule Thief circuit. Another awesome video.
No it was Z. Kaparnik as acknowledged on BigClives website. Big Clive invented the name Joule Thief
@@davidsnell7627 No, I believe he came up with the blocking oscillator circuit and Clive acknowledged him for that. Clive Invented the Joule Thief circuit and I have been making them for over 13 years now and, can even light 400 leds on a single "dead" aa battery and can light fluorescent tubes on that same aa battery. I have JT circuits that put out over 400 volts from a "dead" aa battery. I had 75 videos on my YT channel most of which dealt with the JT circuit. I pulled them all since YT stopped paying me and ran their own ads. I am moving them all to Rumble but it is taking a while. Clive named it the Joule Thief and took it to places that Russian fellow never dreamed of but yes, Clive did give him credit where credit was due.
I realy like the concept of a batteri free kinetic remote. Could you please review a ZigBee compatible kinetic remote as well? I also wonder if the kl4 contain are Schottky diodes?
First time viewer here - where have you been hiding?!? Now subscribed!
RUclips seems particularly bad at recommending electronics enthusiast channels. Even the ones I'm already subscribed to occasionally disappear for months.
Sometimes It's worth checking to see if you've been randomly unsubscribed from the technical channels.
I believe the manufacturing process Clive mentioned is for certain 'electret' devices, with a fixed electric charge analogous to a hard magnet, piezo devices rely on the stress/strain interaction with the charges in certain crystal lattice, for instance if you cleave standard quartz crystal along the right orientations it will naturally exhibit piezoelectric properties.
Been watching a few videos from, Mr Carlson's Lab recently, now they are some old school oscilloscopes that he uses, old school and big. Then you bring out one that is tiny, even smaller than a cell/mobile phone. Nice thing about Mr Carlson's Lab and channels like Fran Blanche, not forgetting Clive of course is, keeping alive old equipment/technology, passing on knowledge and entertaining us.
I love innovations on existing tech, especially when it's neat things like this.
The Quinetic ones must be pretty reliable as several electrical engineers on RUclips install them as standard for turning on/off mains lighting rather than traditional light switches. Especially common for turning outdoor lighting on/off from indoors without having to run a wire. They are priced accordingly of course.
That's amazing how the heat it up and cool it down to get it to keep a voltage across... like magic : )
That transistor operates exactly like a "crowbar" component in some power supplies, but for a different purpose.
A PS crowbar shorts the main DC rails to force a fuse to blow so that the expensive stuff doesn't fry (theoretically). This transistor shorts the "power" rails simply to reset the MCU. Clever as hell.
We were all thinking that first one was piezo and were disappointed when you opened it up- thanks for finding one that was!
Is the MCU effectively browning itself out with the transistor then? What what came to mind when I saw it.
First time I've seen a uc that commits suicide by shorting it's own power supply. Weird, or maybe genius.
@@DansKoiPond Pretty much, yes.
@@raykent3211 As long as it reliably comes up in a known state when the power comes back on, and apparently it does, think of it as being resurrected- or respawned- if you like.
@@markfergerson2145 since I posted I've read another comment that reckons it's not a transistor but a chip that delays reboot until the supply voltage is good. I think I'd bet on that, how about you?
My outdoor floodlights were installed all on separate switched in different rooms... (stupid contractor) so I used this kind of switch with receivers for the front and another for the back and they worked great. I could control all from in the family room. However, I now leave the switches all on and put Alexa controlled floodlight all around so I can do voice, or they are linked to the motion sensors and cameras... But Pre-Alexa, I really needed this kind of switch and they worked well.
They need to make car remotes, TV remotes and garage door remotes like this.
I have bike lights that turn each other on and off. Including the ones with no radio transciever/reciever No encoding.
"Big Battery" won't like that ... 😁
I still remember the day in 1968, when I could turn of my bedroom light from under my covers,in my cozy bed. I added a string to the pull chain light socket in the ceiling light :-) Now I can dim, change the colour or turn off the whole house with my big toe using a click switch stuck to the foot of my bed.
An interesting video effect on the lined writing pad. The lines look as though they break for the circuit sketch. Maybe a compression artefact?
It would have been interesting to scope the data line, to gain an insight into the code used.
With such a short transmission, the receiver must be active all the time. I.e. no power down and no squelch. This must be demanding for the code used, as the receiver has a finite probability of decoding a valid code from the noise.
That's really nice. I wonder what the RF antenna is like, possibly there is something that can be done there to increase the performance..
I wouldn't have thought it was possible to do it this way. The voltage those piezos give off is more than enough but the current is incredibly low. But apparently that's all it needs. It's incredible that it can be done that way. By the way, piezos are one of those few components that usually still have lead in them, as the most common and best piezoelectric material, PZT, is lead zirconate titanate. I wonder how that factors into RoHS compliance.
Thanks Clive.
Oddly reminded of a gizmo my grandmother had for her TV. Grandpa was into building electronic kits from the back of magazines, and so there were all sorts of odd gizmos around the house. Pushing a button on the box she kept by her chair snapped a spring against a small metal rod, and there was a box on the TV that picked up the chime sound. It was quite high pitched and tinkly. Sometimes other things in the house, like dropping silverware or keys would set it off, and bring cursing from the living room, as the channel suddenly changed during granny's soap opera. Also in common with this: it worked about half the time.
Those audio remotes were very common in early TVs.
Now I have to get one.
I'm afraid we *all* do. 😶
Fortunately it's not too expensive.
@@ParedCheese dammit, me too.
@@bigclivedotcom Depends on that you consider expensive. I have a only a small hobby budget to play with.
I'm pretty sure that the part labeled "C645" is a low voltage reset IC which holds the MCU in reset when the supply voltage is below 4.5V. Also, the reference designator on the PCB is U1 which points to an IC. If it was a transistor, it would normally be labeled Q1. It's probably a BL8506-45CRM
www.belling.com.cn/en/media/file_object/bel_product/BL8506/datasheet/BL8506_V1.9_en.pdf
Nice video Clive. I would have liked to see you capacitively couple your oscilloscope to the transmitter antenna to see the signal and get a sense of just how much power these little switches can transmit.
I think that C645 is definitely not a transistor since it use 'U' as prefix, also this C645 marking is being used by BL8506 Voltage detector IC.
As a side, could you review that wee oscilloscope please? I've been looking for a small one (I don't have the space for a larger one), but I expect the smaller ones will most likely be trimmed down in features/capabilities - so a quick review of it would be useful
It's a DSO Nano 3 I think, I want to know more about it too
Very interesting. It would also be interesting to see the RF signal data coding format. Do you have scope capable of capturing & displaying that data packet/s?
Nice work! Thanks for sharing!
Capturing would be easy, just hook the digital scope up to the microcontroller's output pin. The scope might have a hard time decoding the signal automatically but it should be simple enough to decode by hand.
AC1 = Actuator 1
AC2 = Actuator 2
COM = Common
One actuator is on, other is off as the codes are different.
Usually in programming mode, sending a OFF deletes the code, sending ON programs the code.
By wiring in just one like they did they can instead use code that sends the on and off alternately and it may also explain why it does not always work after being idle for a long time.
Alternatively what you assume is a transistor may be a ultra low quiescent current regulator delivering 0.8-1.8v for ram retention in the mcu so it can remember if it sent the on or off last. That also explains the large 2.2uF tantalum capacitor.
The scope probes are sucking the 2.2uF capacitor dry in the video.
2.5v on 2.2uF has a time constant of 2.2 seconds. I believe the sending of the code is triggered by reaching 4.5v and the first click down on the button only charges part-way.
Releasing it gives it another kick and it reaches it's target and now has enough energy to transmit.
You can test this by clicking it in and waiting for it to drain and see if it still transmits on release or transmitted already.
C645 is a BL8506 ultra low power voltage detector.
Markings are C625 for 2.5v, C633 for 3.3v and C645 for 4.5v etc. C means it has CMOS output to mcu.
Current consumption is 500nA and it is most likely used to tell the MCU when it should transmit. Hysteresis is 4%.
5:43 I thought he had Dooneese hands.
I agree the c645 must be to drain the caps after transmit is complete, so it's immediately ready to detect and respond to the next button push... though it's interesting there's no drain resistor into c645.
Edit: you showed that with scope after all.
I think I would power the microcontroller through a Zener, and have a bleed resistor on the caps to prevent inadvertent charging from massaging the button or even vibration or sound.
In fact that would be an interesting test, whether voltage builds enough for a transmission simply from auxiliary vibration or sound...
I used to use those piezoelectric discs as drum triggers to an Akai box back in the very early 90s to generate midi to trigger samples.
I made a friend an electronic drum pad from a pound-shop frying pan and piezo disk.
Pretty cool, someone had their thinking cap on. Your o-scope interests me as well.
Lol... i was literally typing a request to hook it up to an oscilloscope... and you brought it out. I erased my message and wrote this... the phone monitoring listening algorithm sure works fast!
Big Clive is watching you 👀
@@ursanotsomajor Helicopter! Helicopter! Helicopter!
Love these "self powered" electronics. Came across a vibrator that powered a tire pressure sending unit in the wheel of a car. Driving charged a cap that powered the transmitter.
That magnetic switch seemed much more robust, despite the moving parts.
More functional too: worked on every press instead of missing some and conveyed direction so off can mean off with no chance of it meaning on.
@@tissuepaper9962 what coin cell? I'm guessing you didn't watch the video featuring the magnetic switches.
Nifty
The transistor looks like it supplies a de-bounce function to make sure the rf only sends a single message if the pezio is still triggering when the mcu is done.
It surprised me how sensitive a piezo crystal is to vibration.
EEV Blog has a superb video about microscopy on oscilloscope input channels. Check it out.
They are used as microphones after all.
It's one of the reasons that ceramic disc capacitors are not recommended for use in low-signal audio applications. They're actually microphonic.
I'm wondering if I could make a sensor for my mailbox to let me know (via RF) when someone opens it. A regular make/break switch might not be good because my mail carrier tends to leave the door open.
@@tncorgi92 a novel idea, but it would be more reliable to use an accelerometer.
This is another of those video titles that's going to get picked up by the algorithm I bet!
and you were right
Could the MCU's trigger of the shunting transistor be a method of debounce?
2:30 - Transducers are interesting devices:
My mother was watching an older episode of "Shark Tank" (the US equivalent to "Dragon's Den") and the two guys trying to get a deal were selling standalone transducers as a "stick anywhere" speaker - they already had an established product that was a transducer-in-a-cardboard-box as an external speaker. My mom thought it was amazing, and then I told her I used to see transducers for sale in the pages of the DAK catalog back in the 1990s and this was not "new" technology.
It's something I might tinker with someday, I came across some RUclips videos a few years back where a guy (I think he was an acoustic engineer) actually experimented with transducers and various materials/shapes/sizes/etc. and had some truly impressive results with some of his designs, often with the least-expensive materials. I wish I had remembered the channel because it was very interesting, and renewed my interest in them.
I have no clue why the idea of transducers-as-speakers hasn't been implemented in new home construction, it seems like a convenient and relatively-inexpensive way to bring audio to virtually any room, and it can be easily incorporated into any decor. Seeing the transducers in the 1990s as a teenager, I immediately thought that it would be incredible to walk over to a home audio receiver, select a specific pair of speaker outputs, and go to the room I wanted to listen in and enjoy room-filling sound with no visible speakers. Then, I re-imagined this system with an RF remote instead of IR, so the main receiver could be controlled anywhere in the house, and could select the speaker outputs from the remote. I honestly thought this would be a natural progression in home audio! With today's technology capabilities, you could connect via Bluetooth and stream audio from your phone and have it "follow" you from room to room. How is this not a thing?
This is an extremely unusual idea, but I wonder if this sort of design could be used to retrofit an old Rock Band drumset and make it completely powered by the actual striking of the drums. The pads are just piezoelectric discs underneath of the plastic drum heads, wired into a controller board. I’d imagine one could make a USB dongle that could receive the signals from hitting each drum, as long as it could be programmed to receive each one as a separate switch.
The sensors might end up jamming (pun) each other, unless they use different RF frequencies, which complicates it..?
@@catalinbadalan4463 Each one of them could be a specific signal, doesn´t matter if they are in the same frequency.
@@ArturoValarezoChavez This is not how radio waves work as far as I know.
@@catalinbadalan4463 There would be possible interference but each one having a different “code” that it transmits would possibly mitigate any issues as far as the signal. My biggest concern would be latency since these things obviously aren’t designed to operate within milliseconds.
The circuitry at U3's output is an RF filter network to enhance the harmonic output that is above 300+MHZ and suppress any at 26 Mhz.
Could be but there isn't a harmonic of 26MHz anywhere near 433MHz so I suspect it's operating on another (illegal in UK) band.
@@jeremygreenwood8501 You are right about the harmonics because 26x16 = 416Mhz. The 17th harmonic is in a USA HAM band. I thought that 433Mhz is the band in the USA for Garage-Door openers.
I had one of those stuck to my washing machine, and I got a disco bathroom :D
jocks a side, it's very interesting. and it's possible that they use the multiple input for more than one button to control multiple devices.