Eico 667 issues

I thought I would share my success of bringing a 40-year-old piece of bench test equipment back into calibration. I just got an Eico 667 from eBay earlier this week and was not surprised that it needed a little help.

First, there is some great instructions here, at the Tone-Lizard site. It suggests replacing two rectifiers, two capacitors, and two potentiometers. That was easy.

There was still a problem with the MERIT test, however. I realized that the potentiometer behind the PLATE knob was not working at all. Since it is a 3K-ohm 4-watt pot, it is actually a rheostat. I took the back off and noticed a lot of buildup and gunk in there. I sprayed some CAIG deox-it in there and cleaned it with some swabs. I think I got it back up to spec which is good because I don't know if I can find a replacement for that. The GRID pot is similarly constructed, but with a switch and higher rating, so luckily that was fine.

--gh