[sdiy] BIG PSU ISSUES

[Dave Manley]

Dan Snazelle wrote:
> by the way i wasnt trying to be rude or evasive...i just dont know HOW 
> to measure current. especially split among three BIG breadboards (the 
> kind with 5 verticals rows) thanks all for the help i am so happy i am 
> getting 12 volts again!!
Hi Dan,

Measuring current is easy.  Check the manual that came with your 
multimeter to see what the max current your meter can measure otherwise 
you might damage it or blow a fuse in your multimeter. Basically you put 
the meter in series with one of the supply leads, so that the circuit's 
current has to flow thru the meter.  The other easy way is to put a 
small resistor in series (like your 22r, but smaller so you don't get a 
big voltage drop) and measure the voltage across it.  The current is 
then the voltage divided by the resistor value - look up Ohm's law on 
Wikipedia..  Example using a 10 ohm resistor - if you measured 0.2V, the 
current is 0.2V/10ohm = 0.02Amps or 20mA.

-Dave