Bass circuit problems on model 38-690 - Printable Version

+- The PHILCO Phorum (https://philcoradio.com/phorum)
+-- Forum: Philco Radio Discussions (https://philcoradio.com/phorum/forumdisplay.php?fid=5)
+--- Forum: Philco Electronic Restoration (https://philcoradio.com/phorum/forumdisplay.php?fid=8)
+--- Thread: Bass circuit problems on model 38-690 (/showthread.php?tid=2777)

---

Bass circuit problems on model 38-690 - flradiodoc - 01-01-2011

I am restoring a 38-690 and am having a problem with the bass amplification system. The chassis has been completely gone through and plays great. Only problem is the bass control does not do anything at all when adjusted. I have chased electrons until I am blue in the face and have gone over everything numerous times to see if I can find the problem, but to no avail.
If anyone out there can help me on this one, thanks a bunch.

Mark...

---

Re: Bass circuit problems on model 38-690 - Radioroslyn - 01-01-2011

Hi Mark
I took a quick look at the diagram and my hair instantaneously burst into flames!!!! A poor of a rendering of the diagram on NA very hard to follow! Generally I would check the pot for shorts to the chassis break out the Signal tracer and start at the pot and nose around a bit to hear if there is any bass boost. Key suspects would an open resistor or cap. I know it's not much to go on.
Terry

---