by Eric Brouwer » Wed Nov 13, 2002 9:55 pm
I have build five of my PIC 16F84 interfaces again tonight, and all were tested to work correct (2 for JR, two for Hitec, and one Futaba).
Double check all your components, critical are the transistors, PIC, and zener (mounted correct). With FMS running, and pin 5 of the plug as common, you should measure around +6 to +9 volts on pin 7, and -6 to -9 volts on pin 4.
This means the supplyis fine. Next, measure across the zener, you should get around 5.6 volts. If you measure lower than 4 volts, I can suggest you changing the 470R resistor with a 220R (nothing lower), but only if you measure below 6 volts on pin 7.
The circuit should then be up and running.
Good luck.