[R-390] Possible source for isolation transformers?

[sdaitch at mor.ibb.gov]

I have two step down transformers, designed for 220 to 110, same power rating, and about a 4 to one weight difference:

Stancor GISD 1000, 1000 watts, about 32 pounds

Stancor GSD-1000, also 1000 watts, about 8 pounds.

One thing to remember with autotransformers, far more important
in overseas use, stepping 220 down to 110, is if the primary
side is not wired properly, the "low" side, rather the common side of the autotransformer is actually at 220 VAC above ground.  If everything is insulated properly, it might not be a real problem, but it can be.

73
Sheldon



> 
> So, on that basis, true isolation transformers weigh a LOT more 
> than 
> the cheap autotransformer types.
> 
> Ken W7EKB
>