Corrected 4069 by Martin C

[SC->] Important Note! The CD4069 chip shown here is actually incorrect. The data sheet for the CD4069 shows the inverters pointing the OPPOSITE direction. *** I tried building this circuit and could not get it to work. It seems the "fix" is actually a break. Stick with the original circuits on the other pages and it should work just fine. *** Warning #2: the chip data sheet doesn't recommend leaving the unused inverters unconnected/floating. Probably the best solution would be to tie the inputs to Vcc and outputs to ground.

The contents of this page have been copied (with permission) from HackCanada. The original page can be found here.

I've added a 1m ohm pot to the electrode because when I tested it with the multimeter and oscilloscope I found out that the final output, at the electrode, was building up to 1200 millivolt!

So, there's a pot for the frequency (2hz to ultrasound), another one for the output level, and an on-off switch. The electrodes are made of felt over a shim (0.006 inch thick) of brass welded to the wire. I use standard "salinex" (salt water "nose cleaner"). Here's the little windows program I use to get an oscilloscope out of my pc, using the sound card.

Martin C. 2005-12-23

Circuit Diagram

Finished unit