On Aug 23, 2008, at 7:06 AM, Tom=E1s =D3 h=C9ilidhe wrote:

> When I got my PCB back for my Connect4 I soldered all the components
> onto it but I left one of the LED's loose, reason being that I  =

> wanted to
> use an ammeter on it to see exactly what current I had flowing through
> the LED's.

Shame on ALL of you.  Replacing the LED with an ammeter will NOT give  =

you an accurate pictures of the current that would flow through the  =

LED, because a typical LED has a MUCH higher voltage drop than the  =

ammeter.  You could leave a gap for the ammeter, with the LED in  =

place, and get an accurate idea of the current, or you can measure  =

the voltage across the resistor (as you say) and get a "pretty  =

accurate" picture, but you can't simply put the ammeter in there IN  =

PLACE OF a *relevant* circuit element!

BillW


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