I have an ADA 2FX whose echo has gone south. It had been unused for several years, and I decided to put it together with my Pearce amp. Lo and behold, nothing much worked on it. I cleaned it up, got the flange and chorus working again, but nothing seems to bring back the echo. It makes a sputtering sound, with the original signal sputtering through it. There isn't any delay, and it doesn't matter what length the repeat is set to (the LED blinks correctly to whatever setting you have it on). Also, it hums a bit, but I expect that the power supply caps need replacing after all this time.
Anyone have any idea what's causing the echo to do this? Nothing I do seems to affect it; I moved some of the chips around that are socketed, but it did nothing to the echo. I have the schematics, although they're a little hard to read, but nothing has led me to a decent answer yet. I was so looking forward to having this little mono amp rig up and working for a gig this weekend, but the 2FX doesn't seem to want to work...