replying to purple.acorn, rmotley wrote:
Take a potentiometer rated pretty high such as a 5K ohm 2 watt. Solder a wire
to the wipe and another wire to either end. Connect these wires to your ohm
meter and adjust it for highest ohms. Now disconnect these wires from your
ohm meter and solder them to the circuit board where the resistors leads were.
(remove the resistor first).
Connect your multimeter to the output of the power supply and set it to read
DC volts. Plug in your power supply. Slowly turn the pot to decrease ohms
until you start seeing volts rise on your multimeter. When the volts reach
the level the power supply was intended to output stop. Disconnect the setup
and read the ohms value on the potentiometer . This is the value the resistor
needs to be. I did this with R7 in the wall wart.

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