Broken ground lead from power transformer.. HELP!!!

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Broken ground lead from power transformer.. HELP!!!

Postby GrooveGrinder » Fri Sep 28, 2007 12:33 pm

Hey there...

During re-assembly of my total rebuild project,
the ground wire from the PWR transformer broke
about halfway to the ground lug.

All the wiring was in real bad shape....
It practically came off in my hand.
Its the last inch or so of just about each lead
that were putrid... green and brittle.. heh...
Above that they're ok.
I had to cut off the last inch or so, and strip the ends.
No choice...

Now what do I do???
Pleeease help!!!! :)

I've totally reassembled the amp...
This is the show stopper!
I'm dying to conclude it, and FINALLY hear it!!!!
Its been years since I've used the amp... what
with it being unusable for many yrs, and the time
to save bux, get parts, learn how, and finally build it!

Sooo.. whats the fix?
Add a length of wire with heat shrink sleave??
I know thats not great but.... I have few other
choices!
If so, what guage of wire??
Is there a better alternative?

Thanx sooo much in advance!!!!
Greg
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Re: Broken ground lead from power transformer.. HELP!!!

Postby Ty_Bower » Fri Sep 28, 2007 5:10 pm

GrooveGrinder wrote:Sooo.. whats the fix?
Add a length of wire with heat shrink sleave??


That's pretty much exactly what you do. For transformers (power or output) I'd try to use the same kind of wire as what's left of the existing leads. On my power transformer, all the leads are stranded except the heater windings (they're solid). So use stranded on stranded, and solid on solid.

You can find some nice silver plated copper wire with 600v rated Teflon insulation. It's not too expensive on eBay. Something between 18 and 22 gauge will probably get the job done. I just got 100ft of "Delco E149" wire from a seller named Auto_trans8. It was pretty cheap, but shipping took a little longer coming from Canada.
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Postby TomMcNally » Fri Sep 28, 2007 5:15 pm

Any old wire will work fine, either heat shrink it or
slide a piece of insulation/tubing over the splice.
Nothing critical at all here.
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Postby mesherm » Fri Sep 28, 2007 6:54 pm

Trim the old wire and a piece of new wire with each end bare for about 1/4 inch. Twist the strands together and then form each 1/4 inch length into a hook shape. Connect the two hooked wires together and squeeze each hook closed with needle nose pliers. Solder the bare wires together and wrap the junction neatly with black electrical tape.
Mike's N-1 Rule: When looking for N number of components to finish a job, you have a 95% chance of only finding N-1 of them.
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Postby GrooveGrinder » Fri Sep 28, 2007 7:26 pm

Thank you all sooo much!!!
No words are sufficient.
Do you realize what this means?!?!?
Means... I might be up and running for the weekend!!!
WooooooHoooooooo!!!!

Really, thanks again guys!!!

Greg
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Location: SoFla


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