Hohner/Elex K4 need info on power supply build

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Brian G
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Hohner/Elex K4 need info on power supply build

Post by Brian G » Thu Apr 19, 2018 4:00 pm

Help!!!!
the power supply is ify at best, and the cord connector at the back of the keyboard is awlful, did some soldering works, ground appear good, but still getting some noise and hum..caps? any help would be appreciated, the pedal on the external power supply does not work, really do not need it I guess, any plans for a new build power supply would be appreciated, thank you.

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madtheory
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Re: Hohner/Elex K4 need info on power supply build

Post by madtheory » Fri Apr 20, 2018 8:34 am

You will need an oscilloscope to check for ripple in the supply. Likely the caps, yes, but could be rectifiler fault too. Don't guess. Test.

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adamstan
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Re: Hohner/Elex K4 need info on power supply build

Post by adamstan » Fri Apr 20, 2018 3:29 pm

My Elex was humming too, but the bad capacitors weren't in the PSU - they were on chorus boards.
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