I have been trying to get this circuit to work for a few days and it is driving me nuts!
I'm trying to make an array of tricolor LEDs (RBG with common cathode). The goal is to use 5v logic to turn on MPSA92 and light up the array.I have 4 LEDs with three anode resistos (one for each color). I'm working with just the red now, as the others will be clones of the same circuit. When I connect the emitter to to +13v, base to ground or +5 through any resistor and collector to the array, it lights up. Only when I disconnected the resistor (open), does the array turn off. I have tried base resistors from 200 ohm to 200k ohm, and the same deal. When I use +5v on the emitter, however, the circuit works as it should. I feel like I am missing a fundamental property of PNP transistors. Any suggestions? -- You received this message because you are subscribed to the Google Groups "neonixie-l" group. To post to this group, send an email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/neonixie-l?hl=en-GB.
