[Amps] 813 Filament Transformer

[Steve Thompson]

Steve Flood wrote:
> I am building a 2x 813 amp and am looking for a filament transformer.  I need some coaching on a couple options since I cannot seem to locate a proper 10V 10A transformer.
> 
> 1)  Use a 13v @ 20A transformer with a Variac.
> 
> 2)  Rewind a microwave oven transformer secondary with 10 turns of #12 THHN.
Either should work fine - it's fairly uncritical. I used a pair of 4.5V 
50VA transformers - 4.5V is a common stock voltage over here - which 
also provides a convenient centre tap.

Don't forget to remove the shunts if you use a microwave transformer.

Steve