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JPAC and PSU - what to unplug?
mgb:
Oh ok, I get it.
I assumed that you can just let the 5volt, etc stay.
I did miss something ;D
Arch:
@BobA: Worked like a breeze! I had the fire exstinguisher at the ready when plugging it in, but I had no hassle at all, so thanks! :applaud:
On a sidenote, the isolating transformer gives off a constant high pitched hum of sorts. It also did this before I did the rewiring. Is this normal?
BobA:
The very noticeable hum or whine is often due to the laminations in the transformer getting a bit looser with age. Seems to be a common problem with older units. Don't think there is much you can do about it except replace the transformer. Even some newer transformers hum a bit.
mgb:
here's an article from Bob Roberts about that
http://www.therealbobroberts.net/iso.html