AA5 hum

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AA5 hum

gregb
Senior Member

Posts: 599
Threads: 24
Joined: Jan 2014
City: Edmonton AB CA

10-21-2018, 12:04 AM

I just repaired an AA5 set for a customer yesterday and it had rather weak reception and I have seen this problem before. There is a low value capacitor, approx. 100pf, in the grid circuit of the convertor tube and it had gone bad. I have had three sets now that had poor reception after a recap and changing that cap brings it back to life. They are usually a silver mica or a ceramic cap so are not normally changed in a rebuild. Might be worth a try in your case.

Gregb

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Messages In This Thread

AA5 hum - by fenbach - 10-18-2018, 11:02 PM

RE: AA5 hum - by Radioroslyn - 10-18-2018, 11:28 PM

RE: AA5 hum - by Jayce - 10-19-2018, 12:05 AM

RE: AA5 hum - by Chas - 10-19-2018, 12:09 AM

RE: AA5 hum - by fenbach - 10-19-2018, 08:18 PM

RE: AA5 hum - by fenbach - 10-19-2018, 08:20 PM

RE: AA5 hum - by Chas - 10-20-2018, 12:04 AM

RE: AA5 hum - by gregb - 10-21-2018, 12:04 AM

RE: AA5 hum - by David - 11-04-2018, 03:20 PM

RE: AA5 hum - by Jayce - 11-04-2018, 09:24 PM

RE: AA5 hum - by 35Z5 - 11-05-2018, 09:57 AM

RE: AA5 hum - by morzh - 11-05-2018, 10:48 AM

RE: AA5 hum - by Squire - 11-08-2018, 01:12 AM

RE: AA5 hum - by fenbach - 03-16-2019, 11:12 PM

RE: AA5 hum - by Arran - 03-16-2019, 11:49 PM

RE: AA5 hum - by 35Z5 - 03-17-2019, 05:55 PM

RE: AA5 hum - by fenbach - 03-23-2019, 07:54 PM

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