Let me start by saying that I'm having difficulty trying to test my NTE 2989 N-Ch MOSFET or any N-CH. MOSFETS. I'm testing with my digital multi-meter I followed this testing tutorial on YouTube, but didn't got the same results.
Intead of me doing a video conducting the MOSFET test, I instead...
I have a device that I took off an Avermedia document camera, It has 4 lasers and bright white LED's I would like to power it with batteries, but how can I find out how much voltage is need it?