Re: 60's Ampeg B-15 blowing fuses

On Jan 5, 11:40 pm, "Stephen Cowell" <scow...@xxxxxxxxxxxxx> wrote:
"senator richards" <rnewma...@xxxxxxxxx> wrote in message

news:fd9ff3ca-e206-41f4-9b39-fd17f3a99121@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx

I recently bought a 60's Ampeg B-15 knowing it would need some work.
It was blowing fuses so i suspected a cap or resistor. Brought it
home, opened it up and checked the caps and resistors in the power
section and everything seems ok. Put in a new fuse, pulled all the
tubes, turned on the power with the standby switch off (on standby)
and the fuse blew again. At this point I disconnected the HV supply so
all that is still connected to the PT is the filaments, and it still
blows. The windings on the primary and secondaries of the PT show low
ohms but don't test as shorted. What should they be? Is this PT toast?
Thanks for any help.

What was the size of the fuse you first pulled out of it?
Did you look?  Never buy an amp with a 20A fuse in it!
__
Steve
.

There was no fuse or tubes in it when I got it. I knew it was going to
be a project and I got it for a good deal. Everything inside the amp
looks clean, no hack repairs.

RN
.

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