Power Transformer with Dual HV Secondaries Pt. II

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I had previously posted about two large power supplies I acquired, and I determined that they are from Hammond Organs, Model H-100. The power transformers are pretty big, measuring 5.5" by 4.5" by 6" and have copper Faraday shields. Each supply also has two large chokes, also with Faraday shields.
The transformers and coils were made by Midwest Coil and Transformer. The PT part number is AO-30421, and the chokes, AO-25319, all made in 1967.
The power transformers each have six secondary windings: two unequal HV windings, two separate 5AR4 heater windings, one 6.3V winding, and one ~50V winding for the organ's Solid State circuitry.
With no load, the HV windings measure 500-0-500 (50 Ohms per side from Ground) and 408-0-408 (40 Ohms per side from Ground). It seems the reason they are rather high is that this power supply was designed as a Choke Input PS.
No one in the Hammond Organ world seems to have the original transformer specs, but here's what I calculated from the schematic:
500-0-500 Winding: B+ Output 400V @ 150mA (at idle--supplied 2 x 7591, plus others)
408-0-408 Winding: B+ Output 310V @ 260mA (at idle--supplied 4 x 6BQ5, plus others)
5.0V x 2: at least 2A each for 5AR4s
6.3V Filaments @ 9 Amps (the organ's tubes have a combined draw of 8.89 Amps)
50V @ "hundreds of mA" according to a knowledgeable source (would easily power a bias supply)
My previous question had concerned the best way to use these for Monoblock Power Amplifier supplies, wondering if you could parallel the HV windings. After seeing the ratings, I realized that one of the HV secondaries alone should be more than enough for a pair of output tubes, KT88s or EL34s. The other HV secondary could be used for the driver tubes.
I am considering, since there are heater windings for two 5AR4s, if I couldn't use two 5AR4s in parallel for the pure excess of it. Would it cause any problems to have two separate heater windings meet at one point, where the B+ came off?
Also, there is the question of whether to keep Choke Input or go to Capacitor Input for higher voltage, say, for the Output tubes, and keep one winding on Choke Input for the driver tubes, perhaps with some smaller tube rectifier, since I read that Choke Inputs do provide better regulation.
Am I thinking in the right ballpark, or too small? Basically my idea with these was to have Power Supplies that have plenty of reserve for a pair of standard monoblock push-pull power amps. And I got them cheap with a bunch of other parts. The chokes are only 40 Ohms each and are as big as some small output transformers I've seen.
Hammond generally used fairly conservative designs since they were aware than an organ might be left on for extended periods. There was a tendency to over-engineer.
David

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Topic - Power Transformer with Dual HV Secondaries Pt. II - David Anderson 18:44:23 01/29/07 (6)

First find the schematic and bridge the chokes and find out their inductance.. - grhughes 07:32:14 01/30/07 (2)

Re: First find the schematic and bridge the chokes and find out their inductance.. - David Anderson 12:33:20 01/30/07 (1)

I would just build on what you have..... - grhughes 13:58:17 01/30/07 (0)

Given that, what are you asking? - Chris O 05:56:23 01/30/07 (2)

Re: Given that, what are you asking? - David Anderson 08:11:10 01/30/07 (1)

You have all that you need (and more) - Russ57 10:51:38 01/30/07 (0)

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