14-03-2014, 12:27 PM
In the absence of a variable power supply I would go for a 10 ohm resistor and 12 volts.
Measure across the resistor. A computer power supply may well need a load on the 5 volt wire to make it stable such as a car brake light bulb.
You will need to isolate the earth if you are going for 24 volts from a computer power supply.
I would be tempted to go with its own transformer and start with 220 ohms and 10 whats for the resistor and measure the voltage across the resistor.
Measure across the resistor. A computer power supply may well need a load on the 5 volt wire to make it stable such as a car brake light bulb.
You will need to isolate the earth if you are going for 24 volts from a computer power supply.
I would be tempted to go with its own transformer and start with 220 ohms and 10 whats for the resistor and measure the voltage across the resistor.
