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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
Eric
The Villages, FL
Member: Philco Phorum, ARF, ARCI & Radiomuseum.org
(This post was last modified: 04-18-2014, 11:41 AM by
Eric Adams.)
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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
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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,
Eric
The Villages, FL
Member: Philco Phorum, ARF, ARCI & Radiomuseum.org
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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.
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Jon,
You're the best!! That was it!
That's unreal that it was that simple!
Thank you
Eric
The Villages, FL
Member: Philco Phorum, ARF, ARCI & Radiomuseum.org
Posts: 395
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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
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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.