my digital tc tuner

["Tesla list" <tesla@xxxxxxxxxx>]

Original poster: Ben Buxton <bb@xxxxxxxxxx>


Until now, I have been tuning my coil with Terry's TCT and a 
multimeter to accurately measure the resulting resonant frequency. I 
decided I wanted to make something a little more self contained so I 
decided to combine it with a PIC based frequency counter.

This is my resulting device:

http://au.cactii.net/~bb/tesla/dtct.jpg

So now I just adjust the dial until the LED goes bright (sec) or dim 
(pri), then I can read the frequency off the display for < ~1KHz accuracy.

I used this frequency counter circuit (variant 1):

http://www.qsl.net/dl4yhf/freq_counter/freq_counter.html

Chosen mostly because it uses an LED display - goes much better 
aesthetically with a TC than LCD IMHO. :)

The main concept involves having both circuits on the one board, then 
just joining the output of the TC oscillator to the input of the PIC 
(via a 2k resistor).

It's built on prototyping board, so no neat layout, but if anyone 
wants more details, just ask.

Ben