Replacing type 84 tube with diodes question - Printable Version
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Replacing type 84 tube with diodes question - redcsctrike - 12-29-2025
After a few very tough years health-wise, I am back at restoring my grandparents Philco 41-285 radio. I am planning on leaving the type 84 rectifier tube in place with just the heater in circuit. I am replacing the tube with either two IN5408 rectifier diodes or I could use 6A10MIC rectifier diodes which I also have on hand. I know I would need a resistor to reduce the voltage after rectification to match the approximated 20v drop in the 84 tube. My concern is because of the inrush of voltage/current do I also need have a thermistor on the primary side of the power transformer or on the output of the diodes? If I do install a thermistor, what size should I use? I certainly appreciate any guidance. Thank you in advance!
Roger