Timer555 frequency issues

ian field

Joined Oct 27, 2012
The capacitor connected to pins 2 and 6 is suspect - do you have any film capacitors near .1 uf?


You can get ceramic capacitors with good stability, but they're probably rare and expensive in the value the TS wants. Mylar is probably as good as any film type, polycarbonate might be better - but maybe not better enough to justify the price.

The capacitor on the CV pin is traditionally 10nF - using 100nF there would multiply any undesirable characteristics of the dielectric type.