I've got two projects with 555 based LFOs. one is an APC/Atari Punk Console (so that is a lot of 555s in a box) - the other is based on Graham's Phat Philter Bank for the Casio SK5, a mono Voltage Controlled Filter.
I find that the LFO affects the output regardless of whether the control voltage line is connected or not!
Crazy. In the Filter circuit it introduced a very obvious *click* in time with the rate of the LFO, and in the APC turning on the LFO (though still not connecting CV lines) causes pitch changes.
Do I need to shield my CV lines - could that be the problem?
What else could it be?
Thanks in advance
if anyone else is having this problem:
https://sites.google.com/site/flofxdiy/deticking-lfo
I ended up sticking a 100nF cap over the positive/negative terminals which reduced the clicking significantly - but it is still slightly present.