I thought you were 0.006 wire that needed 400mA?
this is where I get a bit confused on amps. going to rubber ducky it... so amp rating on a transformer is how much you can pull and volts is actually volts of what comes out of the transformer.
I need 400mA or .4A so....
I have two 6in wires, thats 7.8ohms *2 = 15.6ohms resistance in the wires. and I have another transformer that is 12v 1A:
(12v/.4A)-15.6ohms = 14.4 ohms
ok so I need to add a resistor to this circuit... so it would be more accurate to do this:https://www.dropbox.com/s/aap9xehi068knlp/Screenshot%202013-12-13%2015.34.10.png
so by using those resistor values I am limiting current to .4A? I am not sure if that works with how I have it wired. Also since its going through the transistor would I still need a high watt resistor like a 5w? when I connected directly to transformer, it seems to be an issue, but when I had it on the tip120 it wasn't an issue, so not sure if it was limiting current somehow?
edit: also looking and schematic it seems I could simplify the pin out with just one R1 resistor as well...