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  1. hevans1944

    Name that switch!

    Now that sounds pretty damn clever! Did the pressure bulb make the audio feedback, sort of like a Whoopie! cushion does when you sit on it? If it is no longer made, I am curious as to why. Not enough market to be profitable? Audible biofeedback didn't help to decrease or eliminate bruxism...
  2. hevans1944

    Name that switch!

    Okay, perhaps I misread the OP's intent when he said, "...I'd like to build a device that detects when my teeth come together while I'm sleeping." If not for diagnostic purposes, and perhaps to awaken him (like bed-wetting alarms do) when it senses bruxism occurring, why build such a thing at...
  3. hevans1944

    Jacob's Ladder help

    The "safest" way to power a Jacob's Ladder is with a neon sign transformer, which is constructed to be current-limited when the secondary is shorted. The transformer from a microwave oven has no such current-limiting because it is designed to deliver a kilowatt or so to the magnetron oscillator...
  4. hevans1944

    Trouble with solder

    If it's an aluminum casing, you will never be able to get the solder to stick. Best thing you could do then is to fasten a steel band-clamp around the casing, after soldering a wire to the band-clamp. Make sure the area under the clamp is clean and perhaps apply a dab of lubricant to keep it...
  5. hevans1944

    Name that switch!

    The mouth appliances neither diagnose nor provide therapy for the problem. They just prevent the teeth from becoming worn down. With a method to detect and perhaps record when the bruxism occurs, a course of treatment can be monitored to see if the treatment is effective or not. I think most of...
  6. hevans1944

    Name that switch!

    Not so crazy. You could plug one end of the plastic tube with a stopper (or heat-seal it closed) and attach the other end to an external pneumatic pressure sensor like this one: Above image copied from here. This isn't a switch. It is a piezo-electric sensor that responds to pressure by...
  7. hevans1944

    Noob inside !

    Welcome to Electronics Point, Adrien. I am not so sure that this is the best place to learn written English, but you should be able to learn some electronics here, with or without the aid of Google translate. It appears that at least three languages, Dutch, French, and German are spoken in...
  8. hevans1944

    Can anyone help identify these components please

    The two blue components (one with a label stuck to it) look like high voltage capacitors, but it's not obvious whether they are electrolytic capacitors or plastic-dielectric capacitors. The one that I can almost see appears to have markings: 2μ2 K 250V whatever that means. Someone else here will...
  9. hevans1944

    Name that switch!

    That clearly won't work because the lower jaw moves from side to side, destroying the like-pole alignment necessary to keep the teeth repelling each other. You need to also fit an external fixture that keeps the jaw from moving sideways, perhaps secured to the skull with fine-pitched screws to...
  10. hevans1944

    Name that switch!

    Looks like you (or a friendly dental technician) will have to build one. There is some research being done in this area with force sensors and electromyography. See here for example. Unfortunately, current efforts look more like kludges to me. You might consider using a very small reed switch...
  11. hevans1944

    PWM

    @Gryd3 I forgot to mention that the threshold detector is usually preceded by either a band-pass or low-pass filter to extract the bass components of the audio, if all you want to do is detect the music beat. Thanks for catching that.
  12. hevans1944

    Motor running problems

    It's really hard to avoid shoddy electronics appliances these days. It used to be if something broke during the warranty period you could take it back to the seller for replacement or repair. Not anymore. You have to jump through all sorts of hoops to get warranty "service" nowadays. Easier to...
  13. hevans1944

    8-Pin Development Board

    Did you remember to disable the A/D converter and the comparator before trying to use any of the GPIO bits as input or output ports? This is quite an ambitious μP for a "beginner" to learn with. What do you intend to do with it?
  14. hevans1944

    Oscillator and transformer project

    You could try driving your step-down "filament" transformer in a resonant mode. Drive the low-voltage side with a square-wave oscillator and place a "tuning" capacitor, value TBD, across the secondary. Vary the frequency of the input to find the resonance frequency. Be careful to reduce the...
  15. hevans1944

    Motor running problems

    I don't know how they do it in Great Britain, but here in the states the washing machine motors are generally reversible. One way to agitate, the other way to spin, and usually at least two speeds too. Some sort of one-way sprag clutch mechanism does the gear shift when rotation reverses...
  16. hevans1944

    PWM

    Or you can buy this device from Linear Technology. Voltage control in, you pick the PWM frequency it puts out. But, what will be the effect of PWM modulating a single fixed frequency using an audio signal from the iPod? What does it even mean to convert the iPod audio to a PWM signal? What is...
  17. hevans1944

    homework in RBF "radial basis function" pls help, out of time!!!

    I suppose this has to do with a course on neural networks, and you can read about RBF network classifiers here. But the easiest way to classify smokers versus nonsmokers is by smell... which I suppose uses a neural network of sorts.:eek:
  18. hevans1944

    8-Pin Development Board

    I ran into problems trying to use a 10 kΩ pull-up resistor for a normally-open SPST push-button switch. The PIC10F206 apparently wasn't happy with that. So, I placed another 10 kΩ in parallel with it (to make a total of 5 kΩ in series with the switch to Vdd) and the PIC read the switch input...
  19. hevans1944

    Need help locating timing switch

    I read it (and post #6 too with the nice photo), but the OP made no response to your reasonable suggestions, so I thought I would put my two cents in, for what that is worth. I like the idea of going to a wrecker-yard and finding a used replacement, either the switch or the whole motorized...
  20. hevans1944

    Need help locating timing switch

    Since the switch still works when you manually actuate it, I would work on adding a little extra thickness to the cam-actuated part of it. Maybe a strip of plastic over the switch actuator somehow secured on one end to the switch body... plastic tie-wrap, maybe, or attach with some really strong...
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