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Hewlet Packard transformer

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Does anyone have any information on a #9100-0082 transformer?

I am looking for ratings and wire code.


It has a pair of green 6.3 volts?

a pair of gray

a pair of brown

a pair of yellow 5volts?

a pair of red with a red/yellow which has to be HV

a blk, blk/yellow, blk/red, blk green
 

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burnedfingers said:
Does anyone have any information on a #9100-0082 transformer? I am looking for ratings and wire code.

I took a look through my old HP manuals and found the instrument your transformer was used in. It's from the type 738B AC/DC calibrator. This was essentially a well regulated DC supply with a 400~ oscillator and a power amplifier that used a pair of 6550s in PP with up to 300 volts output. It's a nice transformer. But I think the estimate of 350mA w/choke input is too much. Also, the unregulated DC out was 440V and was on the 6550 plates.

Tube compliment:
2) 6550
1) 12AU7
4) 12AX7
1) 6BA6
1) 6CL6
1) 6AU6
1) 6AV5GA
1) 5U4GB
1) 5651A

I am looking for ratings and wire code.

a pair of green...............6.3V for 2/6550, 12AU7, 12AX7, 6BA6

a pair of gray.................6.3V for 6AU6, 6CL6, 12AX7

a pair of brown...............6.3V for 6AV5GA, 2/12AX7 (regulator/elevated)

a pair of yellow 5volts?....yes

a pair of red with a red/yellow which has to be HV...yes

a blk, blk/yellow.............115V

blk/red, blk green...........115V

blk+blk/red....................230V (blk/yel & blk/grn tied together)
 

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Any ideas as to how much amperage the green 6.3 winding might be capable of? Any way to check this? The leads are thick gauge solid wire.

Quote:
The secondary output is 830 with no load.

Actually upon rechecking this and finding that I didn't get the same reading I changed the batteries in my meter and came up with 870 AC no load and 597VDC on the output of a 5U4 and a 16mfd/600 volt cap. Wouldn't this push the capabilities of this transformer up a little more?
 
Update if anyone is interested

I used the transformer in my "Spare Parts Dynaco" amplifier that I built. It seems to work fine and will run for hours and still run cooler than the stock transformer does. The only glitch was it didn't have a bias tap and this problem was solved in another thread.
 
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