Issue with late 70's Boss CE-1, sounds like parasitic oscillation. ???

[Gtr0]

Okay new information.

I tried the CE-1 today through the clean channel of my amp and it sounded good, so I placed it on my board. right away as soon as I powered up all the effects on my pedal board there was much more noise than usual. Putting the amp on the dirty channel, the amp does the whole feedback thing as in one of the clips in the OP.

I tuned off the CE-1 and the noise and sound of feedback persisted. It wasn't until I unplugged the CE-1 from the power strip that the noise stopped. Even with the unit turns off, it makes my amp "scream" if it is plugged into power. I tried a few different outlets, it didn't always "scream" unless I was pressing on the ac plug in the strip.

So while I have devalued it by changing all of the power caps... it seems there is a different problem entirely. Anyone have a recommendation? I sure appreciate the help!

[Helmholtz]

You should really take care of the sensitivity switch.
Some of the effects you describe look as if it's stuck in the high sensitivity position.
E.g. with a 90mVp-p input signal it should require the level control to be (almost) fully up to get 4Vp-p at point C.
The added gain would overdrive the input with a guitar and maybe cause other artefacts.

Also try to learn how to manually adjust trigger level and timebase settings with your scope.
If well mastered, a scope is the most wonderful tool in electronics.

When I was young I always dreamed of a scope, but couldn't afford it.
It wasn't until 10 years later that I finally got access to one at the university.

[Gtr0]

Thanks Helmholtz! I will most definitely take your advice to heart!

I did forget to mention, I fixed the sensitivity switch before testing it... it was only that the wire snapped off of the switch contact. I re-soldered it and it switches to high and low now without an issue. At testing it was still in low and was about 75-80% of the way up on the pot.

Thanks.