Sorry for the noobish question. I'm a computer scientist, so my electrical engineering knowledge is of the "don't put fingers in electrical outlet" level.
I'd like to know how to power a salvaged scanner light of the type Scanner Light Hack v2.0 from a Canon MP210 scanner/printer. It is a single RGB tube.
I've already discovered the terminals for Power and RGB. I can turn on the light with a 9V battery, no problem. But when I use a power adapter, set to 9V as well, it doesn't work. Actually, I can get the green light to work, but not the others.
I thought maybe it was noise from the adapter? So I added a capacitor, but didn't help. I also measure the voltage with a multimeter, it reads around 9.20. The adapter is a variable adapter, but set to 9V and max output 1700ma. I've tried resistors? Didn't do anything.
I'm not sure what to try next. Anyone have any ideas?