[Top] [All Lists]

Re: [Amps] Alpha 78 failure

Subject: Re: [Amps] Alpha 78 failure
From: Paul Gerhardt <>
Date: Thu, 16 Feb 2012 16:39:45 -0500
List-post: <">>
> The one pin has been 'hot' but the main resistance must be at the
> crimp on the transformer side because the voltage is NOT getting to
> the pin.  A proper repair would be to replace the connector housing
> and install a new pin but I will probably put some sort of splice in
> it for now.
> Back to looking at the Molex list to see if the connector is still available.

Working again Thanks !
I really should try to start at the beginning in troubleshooting.
When I finally got to checking the bias at the tube  sockets it was
fine.  So I checked the filaments and the voltage was very low and not
steady!  I checked it at P1/J1 and it was the same. I put a pin into
the wire on the transformer side of the plug and found the 6.3V and it
seemed fine.   Today I pulled the pin out of the molex connector and
the wire kind of crumbled away from the pin.  I cut off about a
quarter inch of the wire and stripped the insulation back to new
material.  The wire is about a number 12 or so maybe 10 and is really
too big to fit in the pin.  The larger crimp tabs on the pin were also
damaged and some of the material was missing.  I opened up the pins
smaller set of tabs which had been crimped with nothing in them
(because the wire is too large?) I took about one inch of #16 stranded
insulated wire and that fit into the crimp tabs which were re-crimped
and soldered.  The other end of the wire was formed into a loop around
the original wire and soldered and taped.  The pin was reformed and
cleaned with a wire brush and reinstalled.  I connected the connector
and now have proper plate idle current and operation.  I felt the
exhaust of each tube and two were nice and warm not sure about the
other one so may pull that tube and check it.

Paul Gerhardt
FP 274
"You must do this work with love or you fail." -- John Muir, from How
to Keep Your Volkswagen Alive
Amps mailing list

<Prev in Thread] Current Thread [Next in Thread>