I was wondering if anyone could offer some suggestions on fixing on a no-so working EP-3 Echoplex.

I believe it is a late 70's model with the more modern printed circuit board rather than the earlier 70's EP-3's.

When I received it, everything worked but the Echo and Sound on Sound.

After inspecting the inside, I noticed there were a few loose solder joints and I fixed them. I also found a capacitor (35V 100uF) that popped when I moved it a little, and transistor (ones with the little cooling fins on them RCA) that sounded like it was loose and fixed that.

Now, after doing those things, the Echoplex went from doing nothing to producing a faint, distorted, single echo. This was heard with the record level all the way up and the volume all the way up on the unit.

The capacitor was replaced with a known good one and it didn't make any difference.

All the heads have been demagnetized and cleaned, and there are no loose connections.

I was wondering if anyone knew of anything else I could try or replace to get the unit going.

Thanks

I know this won't be of much help but if you did that and got it to work somewhat then I would suggest checking the other parts. Any electrolytic capacitors I would replace as they tend to dry out over time.Or maybe replacing as many parts as possible.
I you have the ability to check the parts(capacitors,resistors etc.) I would pull them from the unit and test them. make sure the resistor values haven't drifted or any capacitior values haven;'t drifted.

Did you re-install the same cap that popped when you moved it??


Best of luck to you~!!

ditto to what NUKLHED said

Ever notice how some old beat up amps seem to sound the best?

Sitting around for years wrecks havok on the parts, which will tend to dry out or leak.

I recently repaired on old CryBaby wah and had to replace every part in the board. Even the resistors were not at their proper values and had drifted quite a bit.

So, as stated Replace all electrolytic caps and then measure the resistor values to make sure that they match the bands on them. Replace if necessary.
Transistors can be check using a meter set to diode to check to see if they are blown.You might have to unsolder from the pcb to test.
That transistor with the foil thingy is more than likely part of the ac rectification curcuit.
The only reason I mention that is you will have to make sure that replace with the right kind of part

Good luck on your project!

George B.