[AMRadio] Transformer help

[Gary Schafer]

I wonder if anyone can help identify a transformer for me.

It is a plate transformer with what looks like a hypersil (sp) core. It
has a single primary with 3 taps. Not sure if it is rated for 120 or 240
volts. With 120 volts I get 1900, 1770 or 1685 volts out. No center tap
on secondary.
The only numbers on it are:  AA 3883  and S179027. Do those numbers mean
anything to anyone ?

It is probably mid 70s vintage.

Also does anyone know how I can tell if it is ok to run on 240 volts
rather than 120 volts other than amount of smoke?

Thanks
Gary  K4FMX