the guy

can you make a quartz crystal vibrate?

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the guy    13

if you take an ordinary quartz crystal and apply a voltage to it, will it vibrate?

 

if not, how do you make it oscillate? and will it be enough that you can feel it?

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swansont    6213

Yes you can make it vibrate; what you want to do is have an amplifier circuit with feedback, where the potential across the crystal is part of a capacitor, so the RC circuit has a resonance. That way you can tune the resistor (or a second capacitor) so that the voltage oscillates at the same frequency as the crystal. There are a lot of different circuit designs that will do this.

 

You probably can't feel the DC displacement, but it will buzz if the frequency is high enough — buzzers use piezoelectric transducers. The displacement is small, but you can stack many of them together. The stack actuators I'm familiar with have a travel of less than 1 mm.

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Ophiolite    1811

As a geologist my natural approach would be to hit it with a hammer.

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the guy    13

thankyou, could you give an example of a simple circuit design?

 

and haha ophiolite :lol:

 

also, what happens if alternating current is used?

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swansont    6213

Google on crystal oscillator circuit. There are many types.

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timetes    10

if you take an ordinary quartz crystal and apply a voltage to it, will it vibrate?

 

if not, how do you make it oscillate? and will it be enough that you can feel it?

 

 

and can you do it from a distance? like...remotely? shut it on and off? it may be a silly question but are these crystals in voting machines? I know they use them in humans for medical purposes........

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swansont    6213

and can you do it from a distance? like...remotely? shut it on and off? it may be a silly question but are these crystals in voting machines? I know they use them in humans for medical purposes........

You could turn the circuit on and off remotely. Any electronics with its own processor will have a clocking circuit.

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TonyMcC    87

Yes you can make it vibrate; what you want to do is have an amplifier circuit with feedback, where the potential across the crystal is part of a capacitor, so the RC circuit has a resonance. That way you can tune the resistor (or a second capacitor) so that the voltage oscillates at the same frequency as the crystal. There are a lot of different circuit designs that will do this.

 

You probably can't feel the DC displacement, but it will buzz if the frequency is high enough — buzzers use piezoelectric transducers. The displacement is small, but you can stack many of them together. The stack actuators I'm familiar with have a travel of less than 1 mm.

 

Did you mean "tune an INDUCTOR (or capacitor)"? A crystal is usually accurately cut to oscillate at a given frequency or one of its harmonics. That manufactured frequency can be changed a certain amount with a tuned circuit - but only by so much. The resonant frequency of a tuned circuit is 1/(2*pi*(SQR(L*C))) Hz. I have never experienced an oscillator circuit that was tuned to a different frequency by changing resistance.

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timetes    10

could that be why so many people today are hearing ringing or humming in their ears? and Ophio's comment.....lolol ....why hitting it with a hammer..lol.... is that what a bug is made out of lol.....when they say if walls could talk...lol

 

last question:.....how would anyone detect one...... like if your going thru an airport....could one be detected in a human going thru a scanner.....or that scanner affect that person....like shutting it off or vibrating it....especially if its a heart monitor......

 

Did you mean "tune an INDUCTOR (or capacitor)"? A crystal is usually accurately cut to oscillate at a given frequency or one of its harmonics. That manufactured frequency can be changed a certain amount with a tuned circuit - but only by so much. The resonant frequency of a tuned circuit is 1/(2*pi*(SQR(L*C))) Hz. I have never experienced an oscillator circuit that was tuned to a different frequency by changing resistance.

 

 

since the crystal oscillates at its given frequency or harmonics..........what would happen if someone with one of these crystals was sitting watching a movie with surround sound with all the vibrations included in that moving........ wouldnt or couldnt that circuit be affected by that frequency?

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swansont    6213

Did you mean "tune an INDUCTOR (or capacitor)"? A crystal is usually accurately cut to oscillate at a given frequency or one of its harmonics. That manufactured frequency can be changed a certain amount with a tuned circuit - but only by so much. The resonant frequency of a tuned circuit is 1/(2*pi*(SQR(L*C))) Hz. I have never experienced an oscillator circuit that was tuned to a different frequency by changing resistance.

 

Yeah, brainfart. R doesn't affect the resonance.

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timetes    10

ok..... like in a remote control........i picked up a universal remote for an old tv...... i had to keep repeating the signal till it picked up the tv signal number. So is that remote a signal generator or a frequency generator? Why would a magnet repel the wave or frequency . Wondering if the oscillation would change the repelling?

 

Whats the difference from a RF and a microwave frequency? is it the heat? again wondering if the oscillation causes the heat? Just a question because these vibrations i've been getting......and zaps......... i was holding the remote while on the cell phone and the remote vibrated and i dropped it......... what would cause that.

 

One last question: can a rf wave cause an electrical wave current?......kind of like two electrical wires causing a magnetic wave.

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