This pair mono mono power amp one channel suddenly humming loudly one day. Old amp so I try to repair by myself.
I unplug all tube and checked high voltage is AC 362V but DC is 445V, feel the voltage is too low (it must be 500V DC). So I think HV capacitor was broke down.
Original capacitor is Tesla 250uF 500V, its withstand voltage seems not enough, so I purchase KEMET ALC70 330uF 600V from Digikey and replaced it.
After running for a few days, the sound is getting better!
The following video is a record of my repair process：(Turn on English subtitles)
Klimo Kent tube power amplifier, repair by yourself - YouTube
I unplug all tube and checked high voltage is AC 362V but DC is 445V, feel the voltage is too low (it must be 500V DC). So I think HV capacitor was broke down.
Original capacitor is Tesla 250uF 500V, its withstand voltage seems not enough, so I purchase KEMET ALC70 330uF 600V from Digikey and replaced it.
After running for a few days, the sound is getting better!
The following video is a record of my repair process：(Turn on English subtitles)
Klimo Kent tube power amplifier, repair by yourself - YouTube
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Nice work, but I would have used 2 smaller electrolytics in parallel, 1 for each elastic band. Can you pass me the wiring diagram? Thank you