Hoffman Amplifiers Tube Amplifier Forum
Other Stuff => Solid State => Topic started by: bibi on November 08, 2017, 09:47:40 am
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Hello,
I have a Schaller KV25 that arrived here in mostly original condition. Everything checks out ok mostly but I do notice that the tremolo controls don't have much function over the length of the pots throw. Only at the very end does the depth pot engage for instance.
I have tried to modify the speed and depth pots with more and less parallel resistance but I'm not having much luck still.
I have measured all the voltages and while they are higher than in the original, even when I have brought them down to the level on the schematic, it doesn't sound any different!
If anyone has an idea for what I could try at this point I would much appreciate it!
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With trem DISabled, does ch2 have about equal "volume" as ch1?
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thanks for the reply, the normal channel has a slightly larger output than the tremolo channel but not by much
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one of the hard part of "unknown" operation is, what did it do new, or normally? Was the trem anemic to begin with :dontknow:
I don't see a lot to "fix" short of a rebuild n see. One "odd" thing for me, F29 wired to the 100k pot wiper.
you could check what appears to be a connector between the 2 BC135s below F29, see if it's corroded, making good connection. I'll keep scratchin my head :laugh:
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F29 is certainly the LDR! It is an odd construction-- I thought of replacing it with another type as that has worked for me in the past. Thanks for idea anyhow!
I have no idea if it was better before or not but now it is basically bad...
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replacing it
That would be a good bet!, LDR make sense now, labeling doesn't :think1: