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Power supply design needed from master designer Terry
#11

Terry,

What are we shooting for on the B + with the two voltage divider resistors? Is it still 90v for this set? I'm seeing 135v on the two plates for the 1J6 output tube on the schematic which leads me to believe it may require more than 90.

Last time we were looking at two resistors adding up to 10K to make up the voltage divider.

Last time I found if I used a 4K from the + side of the 47 mfd to B +, and a 5K between the B + & B -, I got 94 volts. But that was without a load. Once I tried it on the radio, it dropped down to 76 volts, so apparently I need a higher value resistor than 5K between the B + & B -, and a smaller value resistor than 4K from the + of the 47 mfd to B + in order to get 100v without a load.

Greg V.
West Bend, WI
Member WARCI.org


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RE: Power supply design needed from master designer Terry - by NostalgiaRadioTime - 01-04-2022, 12:16 AM



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