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RE: 5R4GY and filter cap values

Posted by Tre' on March 21, 2017 at 17:07:45:
The schematic I found at the link below shows the PT secondary winding at 15 ohms per side of the center tap.

With 47uf the peak current increases to 370mA. Still well within the tubes rating of 650mA.

However if you kick the voltage of the power transformer up to 900vac center tapped and increase the current draw to 200mA. the rectifier peak current becomes 759mA.

The input cap needs to decreased to 4uf to keep the peak current below the rated 650mA level.

The max uf value for the input cap depends on the 'voltage, the current draw and the PT secondary DCR' of the particular circuit one is using the rectifier tube with.

Tre'