diytube.com

This power transformer had 12 tubes on it. 4 x 7591 and 8 various driver stages, etc. would be perfect for a SE KT88/EL34 amp without using an ugly toroid

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No dents.

Asking $45 shipped CONUS

Thanks!

Blair

That's a doubler transformer too. The HV secondary can handle heckuva peak currents

PM sent.



/ed B

Probably sold but if not exactly what are the secondary voltages?

Hi,

Yes, it sold. I do not remember the secondary voltages. B+ on the original design was a doubler that made 430V.

Thanks,

Blair

From my measurements:

With 122VAC 60Hz line voltage:

HV secondary winding is 188VAC no load, and 186VAC, loaded with a FWB and 100 uF cap, feeding a 230V 40W light bulb (246VDC).
The transformer barely gets warm with this loading.

Calculating that the four 7591s consume about 200 mA total B+ current, and applying that a voltage doubler consumes about 3.6X the DC output current,
the 188 VAC winding is then good for at least 720 mA, probably closer to 800-900 mA. It's a beast

I have not yet tried it with a voltage doubler.

Filament is the usual 6.3VAC (7.2 VAC unloaded) for 4X 7591.

Third winding (brown-white-orange) is 55.2 VAC CT, unloaded, this is used for generating 24VDC for the four pairs of
series-connected 12AX7 filaments, and for generating the approx -26VDC for the 7591 grid bias.

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HTH

/ed B