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Have several radios that I reworked in the time frame of 1980-1995. Most are AA5-AA6 sets the parts were purchased mostly from a company call All Electronics the E caps were mostly Nippon you could even buy tubes back then a set for AA5 cost around five dollars. So is it time to recap?
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Hello David ,
Have you used any of those radios lately and far as ones done in the 80s and 90s I would electrolytic capacitors are cheap !
Sincerely Richard
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When i saw this post I thought you were referring to a "recap" job done by someone else? I have such a set, and I will be recapping the recap because the workmanship is just not that great, and the radio performs poorly due to an RF bypass cap being omitted. I can give you an example, the fellow who did it thought it would be a good idea to check the values of the resistors, and replaced the ones he though were out of tolerance, however he replaced the cathode bias resistor on the power output tube, he replaced a 2 Watt resistor with either a 1/4 or a 1/2 Watt, it does not matter which now since it was greatly undersized and scorched. He also piggy backed the cathode bypass capacitor across it, which was not to bright if you want it to last.
I would say that if it was your own work, and are satisfied with it, then maybe try powering up the sets slowly on a variac. Japanese electrolytics are usually pretty good (except for Elnas and Jamecons), and they are new enough that they could be reformed successfully, either with the rest of the set or by powering them up on a resistance/capacitance bridge though clip leads.
Regards
Arran
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The paper caps were mostly replaced with orange drops from All Electronics or AES. I will soon be 77 best that I do the recap for the good of these old sets. David
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I'd kinda wondered the same to some degree. I have a Sound Valves amp & preamp bought new in the middle 1990's, along with a pair of MK3's that had the cans replaced about the same time frame. I haven't used the SV power amp since it blew a tube in the 90's, and the preamp & MK's since the middle 2000's. I liked the MK's so much that I never went back to the SV's or ST70's.
If I could find the place called "Somewhere", I could find "Anything"
Tim
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