RobRob Naked SLO40 Transformer Question

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Hey guys! I want to build the SLO Nakid40 from RobRob’s site, but I’d like to use some of the vintage iron I have taking up space in my shop(not to mention the fact that I don’t want to shell out cash on trannys in our current economic climate. Holy crap are they expensive!) I have a 380-0-380 PT pulled from a Lowrey that had about 100 tubes in it. All my reading says it could supply what I’m doing, but in reading threads on other builds(not the SLO40) several people have said there’s no way to get the B+ down low enough to be useable. Is this accurate? Is it not possible to increase the first dropping resistor value to compensate? Please excuse my ignorance.

Thanks all!!

NR

[PRR]

Amps in the 35+ Watt class are usually "AB". They idle at low current and suck big current when roaring.

A fixed resistor won't drop enough at idle and will sag real bad when roaring.

6L6GC can certainly be worked on a 530VDC supply, around 5KCT load and 40-50W out. But 530V is a very awkward value for electrolytic filter caps, so very few designers went here, so there are few plans to plagiarize.

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Ok, copy that. Thank you sir.