EICO 377 Help!

[kennymutzy]

I got this audio signal generator for free. It works but not completely. Seems like once it gets up to/past 40K/4K etc. it comes on i have signal and can hear sound on speaker. From 40 all the way up to 200k/20K Etc. But as soon as dial gets to 40K/4K Etc. Nothing!
Even on Oscilloscope i can generate a sine wave from 40K/4K Etc. up. But from 40K/4K down not a thing. If I can get any insight or help would appreciate it. I also want to note I went through the calibration via just using a meter. Manual states that it sopposed to be between 10 and 11 volts I have it at about 10.60v. I had to turn the R9 pot up a tad because it was in the low 9’s. Then it said to turn dial back down to the 20K/2K and test again and the voltage should be the same all the way throughout. Well it’s only reading about .440” Thanks for any and all input, advice, or help.

 

[chazix]

It works but not completely.

Welcome to AK. It's been pretty near a half century since I've looked inside an original Eico 377, so please take anything I say with a grain of salt. Might happen that some others with fresher experience will come along. I see there are also some possibilities in the "Similar threads" listing below.

But I'll start with the "easy" stuff. It almost looks like your unit is all original - any idea if that is so? Even if not, I think the electrolytic capacitors should be the main suspects - both the power supply filter "can", and the axial-leaded electrolytic caps (identifiable by having a "+" marking).

To be honest, unless this will be a labor of love, you might be better off using a phone app or something as a generator. It might take quite a bit of work to get the Eico working reliably.