as someone mentioned in that forum, most power supplies will not be stable without a load present, such as a big wirewound resistor. it would be easy to add regardless.

as to the possible need of a load resistor some power supplies do need one but most do not. If the power supply is known to be good and it will not power up add a 5 watt 30 ohm resistor between the +5 volt line and the common to correct the problem.
The cost is about a buck.

A good way to load up a power supply is a light bulb. Not an LED, a regular light bulb, buy a 12v light bulb for a car for example. Radioshack also has 5v light bulbs. Besides loading up the power supply, they will surve as a nice “power” indicator. Another neat thing I used to do is buy Radioshack analog ammeter and wire it in series so that I always have a load indicator. you can see if something is wrong if all of sudden your starting to pull 3-5amps of power through something that should be using 100mA. Indication of a short or leakage somewhere.

iirc you can get the connector at radioshack

@ken true, for devices that use a very small amount of power it could cause issues. Besides heat decipation and fact that your sensing equipment is directly coupled to the measured part. A better alternative in many ways is a hall effect sensor, they are capable of measuring both DC and AC currents and you get a benefit of isolation.

Anyone ought to never test to accomplish something through woodworking without comprehending easy methods to make this correctly. Manufacture sure that you simply require lots of questions when you happen to be in class so that you’re sure you are clear on the techniques together with methods.

I did something similar, but with the addition of a variable voltage regulator. http://www.jamesgibbard.co.uk/electronics/buildinganatxtobenchpowersupplyconverter