From: Enrique V. <ev...@it...> - 2002-05-10 18:21:40
|
Regarding David's question, 2002-05-10: Craig Barnes dixit: > >From what I remember the arrow is always the emitter, the > >direction of the arrow determines NPN or PNP. > > ----- Original Message ----- > From: David Norwood > I am disabled and a friend is building an IR transmitter for > me to use with LIRC and WinLIRC. The circuit we chose is the > "improved" transmitter by Enrique Vidal: > http://www.lirc.org/improved_transmitter.html > [...] > He is having trouble getting it to work on his NT box and we > haven't tried it yet on my Linux machine. He is concerned > that he has built the circuit incorrectly. > [...] > > Another possibility is that I don't understand transistor > > schematic diagrams... in building the circuit this far, I've > > assumed the little arrow facing inwards is the "collector" of > > the PNP [...] Actually, Craig's diagnostic is the correct one. Wiring the PNP transistor in the wrong way will never work! Best, Enrique. |