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Archon Archon is offline
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Default Roland HP-860 electronic piano has HUM

Gareth Magennis wrote:
"Josh9.0" wrote in message
...
No I haven't!
Thanks for the tip, and thanks for the quick reply!
I'll go and try it now.
It has a bunch of different voltages out, and they're labelled on the
PCB!
I guess I should look for ripple on what should be DC, right??
Then trace it back to the offending cap(s).
Then go buy some new ones of those only.

BTW: It has a main voltage going to all the keys of 46V which measures
43V.




You seem to be jumping to lots of conclusions for no apparent reason.
This is not going to help you.


What's with this "offending caps" businsess? You seem to have decided there
is a cap problem and replacing them will be the solution.
Stop guessing, it will get you nowhere.

You need to investigate and gather information. You start with the power
supplies, If they are OK then you look elsewhere.



Gareth.






Thats because searching for any electronics problem on google comes up
with "check all the electrolytics", ESR is the new religion. I get so
many people bringing stuff to me saying, hey its probably a cap, you got
an ESR meter?, can't be more than 10 bucks to fix. Yeah right. A little
bit of knowledge can be dangerous. Good luck to the OP, with a scope
should be an easy fix.