Retronics

The PSU was tested using a 2.2kΩ resistor as dummy load, which when set to an output voltage of 180V, caused a current draw of 80mA.

Oscilloscope measurements show ripple voltage of 3.5mV RMS (the probe is in x10 mode). This gives a ripple factor of 3.5mV/180V = 0.002%. Not bad for a DIY multifunction instrument.

The variable high voltage DC output, in combination with fixed AC outputs of 6.3 or 12.6 volts, makes this PSU suitable for prototyping small vacuum tube circuits.

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Other usages:

• As LED backlight tester
• For measuring capacitor leakage
• For reforming electrolytic capacitors