[AMRadio] Re: GB> 813 filament voltage

SBJohnston at aol.com SBJohnston at aol.com
Sun Nov 5 23:44:27 EST 2006

Thanks for the confirming information on the 813 filament situation.  I took 
a closer look at the amp and found several issues:

1.  Small voltage drop in cold-looking solder joint on primary lug - 
resoldered.  Now 8.9 vac at the fil pins.
2.  Substituted good Fluke RMS meter from my"electronics bench" for junky 
digital meter I've been using on the "rough work" bench - reads 9.4 vac.  Also 
checked it on my favorite Simpson 260 series 8 - reads a hair over 9.4 vac.  

I believe that will be good enough...  I suspect the transformer was 
hand-rewound and I bet he was shooting for 9.5 (5% under nominal).

Steve WD8DAS

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