Frying ic's

[Synsound]

Ok, here's my problem and what I have found thus far:
I have built my 2nd Clari(Not) and both worked great..at first. The one I just wrapped up started fine,. Then I tinkered a bit trying to add a level control for the fuzz. I added a 1k pot in line with the fuzz lift and got a bit of control but decided to keep it stock until I could get a 500 ohm pot. I don't think that would have caused any of the following but I mentioned it just in case.
When I boxed it up tonight it was Dead. I eventually changed out the LM396 and the 78L05 and brought it back to life. It work fine again except for one thing. If I plug or unplug the input it does again. I repeat replacing the IC and regulator and I'm good to go. This only happens if the pedal is powered when i do it. if i plug in the input then turn the power on it is fine.  I am using a stereo input jack as a ground switch as I do on all of my builds ( if it's relevant)

If anyone knows or has any thoughts on what could cause this I am all ears. I would continue experimenting but I'm out of Lm386's

[Synsound]

As a more direct question could a faulty switch or power jack cause this to happen?

[Frank_NH]

I like to use this forum as a learning vehicle, and with your question, I was prompted to read all about the 78L05 voltage regulator and how it works.  Something to add to my knowledge base...

As with any problem like this, it's hard to know what it might be without some pictures, but looking at the layout I would check and double check the orientation of all 47 uF capacitors.  I'm wondering if one of those caps around the 78L05 is discharging suddenly when you plug in.  If that looks good, then check all of the usual things (solder bridges, offboard wiring, cold solder joints...).

Good luck!

[Synsound]

Thanks
I will double check those tonight.

[Synsound]

I have checked the orientation of all of the electrolytics and they were correct. I swapped out the DC jack and foot switch. I also skipped the switching input jack. It now works even when plugging and unplugging while under power. I will test the switch power jack in anothe simpler build but I went through to many parts to keep fighting for an answer here. I will gladly write the few parts off as junk and be happy it's running. Thanks for your response.
Bob

[Jopn]

I forget which of the forums I read this on, but I read that the PT chip's max voltage is 5v.  And while in theory putting the 5v regulator should keep it from running above its max rating, a lot of the common PT failures can be remedied by putting a small resistor between the regulator and the chip so that the voltage dips a hair lower into a safer range.