jrz126

I'm currently building a solid state tesla coil http://www.personal.psu.edu/jrz126/i...d_the_coil.JPG. and I am trying to use a fiber optic cable to control it. (basically I just need a 10-300Hz signal).
I picked up some of the TOSLINK transmitters and recievers from digikey and 50' of cable. It turns out though, the reciever has a minimum operating speed of 0.1 Mb/s (is that a frequency of 100kHz? or would it be 200kHz?)
If I try to run it at the 10-300 Hz, I just get a random 20uS-40 uS pulse.
I tried using a couple of 555 timers and an AND gate, The one timer was set up to run at 400kHz and the other was variable from 30-300. The variable signal was fed through a high pass filter and and'ed with the other signal, so this produced short 400kHz bursts on the reciever. It seems to work pretty good, but I'd like to possibly find something alittle more robust.

Is there a way to use a phase-locked loop or something to get an accurate signal?

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Jeff Zimmerman
To the optimist, the glass is half full.
To the pessimist, the glass is half empty.
To the engineer, the glass is twice as big as it needs to be.

phalanx

You aren't screwing around with that Tesla coil! That sucker is big!

Probably the easiest way to get what you want with the fewest parts as possible is to simply use a PIC10F. You can program in the exact pattern you want and have it all in a tiny 6-pin SOT23 package.

Sceadwian

If the max baud rate you're going to be transmitting at is 300hz and your circuit works what do you mean by more 'robust' ? Do you really need a high speed data pipe to a tesla coil??

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jrz126

Yeah, its a big coil. I'm hoping to set a world record for a coil of this type. (just need to get an arc over 81")

I've heard of other people having problems trying to use these recievers because of noisy environment. They would get false triggers because of the noise.
My circuit appears to be working, but I'm only up to 1/4 of the final power.
So I was thinking that if I was using a PLL or something, it would be more immune to the noise.

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Jeff Zimmerman
To the optimist, the glass is half full.
To the pessimist, the glass is half empty.
To the engineer, the glass is twice as big as it needs to be.

Sceadwian

A PLL isn't going to do anything about noise unless you increase the order of your filter. What exactly is the receiver supposed to do and what kind of environment is it subjected to?

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