Green Ringer trouble.

[stratman672]

Hello, I built a green ringer and the effect works fine at first. But after a while of being on the effect starts to crackle, and eventually it becomes an overpowering roar of static that drowns out the signal. If i unplug it from the dc and it goes away for a while, depending on how long i have it unplugged. This is strange and i've never had a problem like this. Any ideas?

http://www.tonepad.com/getFile.asp?id=90

[stratman672]

to further weirden things. One time I plugged it in and it started out with a completely clean signal (no green ringer effect) and then it started crackling and the effect came in intermittently and then stayed on.

[Mark Hammer]

When things happen over the space of a couple of minutes, it is very often the behaviour of one or more electrolytic caps that is in question. Not always, but often.

[stratman672]

yea I just tried disconnecting the only electrolytic capacitor on the circuit (it was able to function without it) but it still did the same thing..... after a while it started crackling and drowned out the sound. Could any of the other non-electrolytic capacitors have anything to do with it? Ive had a suspicion it could just be cold solder joints.... is it possible for them to cause something like this. (im kind of a noob so i dont know if they could cause intermittent problems)

[Mark Hammer]

Actually, I was thinking more in terms of replacing the cap/s in question, not removing them. I think if you browse through the threads in this particular forum, you'll find that caps can be a problem when they are not up to spec. Electrolytic ones have a tendency to dry out over time. Some people also report that such caps have to be "formed" via the application of voltages in a certain way (which I don't quite understand myself). The gist is that, as decent and reliable as most electrolytic caps are, once in a while, for any of a number of reasons, you get one that is not quite right. They're cheap. Just replace them.

[stratman672]

Hey i switched it out and it worked. I wonder why the old one didnt work because it was brand new from mouser. The one i replaced it with was exactly the same... a little less compact but same capacitance and voltage and everything. This one might have been a dud. Or it might have been in need of "forming" like you mentioned earlier. Thanks for all your help! :-)