Stuck on GE model 220-FOUND IT-tnx-Jon -
Eric Adams - 04-18-2014
My newest project. Am works great. SW has no sound. No static or anything.I did a full recap, checked resistors, tubes are good and the coils checked ok. The weird thing is that I was able to do an alignment on both AM and SW. I was able to follow the instructions for SW alignment. Got a tone loud and clear when and where I was supposed to, but that's all I get.
Any ideas?
Thanks.
GE 220 Schematic
RE: Stuck on GE model 220 -
PAradiogeek - 04-18-2014
Eric,
There is a very recent thread on another forum where someone was able to hear signal generator tone, but no stations. Virtually identical problem. I haven't checked on that thread in a few days, but I believe they had it narrowed down to one of the trimmer caps on the 1st IF transformer. Might be worth a read.
Good luck.
Jon
RE: Stuck on GE model 220 -
Eric Adams - 04-18-2014
Jon,
I read the thread. Nick's problem was no reception on any band. Mine works fine on AM. My problem is with SW only.
Thanks,
RE: Stuck on GE model 220 -
PAradiogeek - 04-18-2014
I know you said that the tubes test good, but have you tried a different converter (12SA7) tube?. The RF tube isn't in the circuit on SW, so it can't be that. I wonder if the converter is marginal in-circuit, even though it tests OK.
RE: Stuck on GE model 220 -
Eric Adams - 04-18-2014
Jon,
You're the best!! That was it!
That's unreal that it was that simple!
Thank you
RE: Stuck on GE model 220 -
PAradiogeek - 04-18-2014
You are very welcome. I've read a lot of posts and converter tubes seem to be a little finicky sometimes. Moreso than other tubes, at least that is my impression.
Make it a good day.
Jon
RE: Stuck on GE model 220-FOUND IT-tnx-Jon -
morzh - 04-18-2014
I had a proble with 6a7 pntagrid where the Brodcast worked and 1/2 of shortwv did, but below 7MHz it would stop oscillating.
They are finicky.