Ignoramus8975 wrote:

I would like to get some clear idea on how to test components of what
I build.

Say, just a servo: can I test it by connecting a small DC power supply
to + and - cables and gradually increasing voltage? I should see it
run, right?


If you are talking about the dc motor that will work. Depending on the voltage you need,
a dc welder can be a good source of power to test high current dc motors.


Or, a servo with amplifier: give amplifier power and apply small
voltage to the +/-10v command input. Then it should move the servo
motor. Right?


Sure. You can make a battery box to provide an adjustable 0-9 vdc command signal by
attaching a 9 volt battery to a 10K linear taper potentiometer.

Rather than use a number of words describing it, I'll just link a picture of a voltage
divider.

http://upload.wikimedia.org/wikipedi..._with_load.png


Wes