Button Pusher for Time-Lapse Photography
[snip]
> Since the relay requires at least 12V, and a fair amount of current,
> I used a MAX232 chip to convert the incoming 6V from the battery
> pack to a much higher voltage the relay can use, and a large
> capacitor to store that charge between presses. The two-transistor
> coil driver was suggested by James in the .design group, but the
> resistor values are all my fault. Thanks to James and all the
> others there who helped me figure this out.
If your relay coil resistance is really 100ohm, I don't see how that MAX232 can supply the needed 120mA. From the datasheet, the MAX232 can only supply about 10mA (short circuit), but this is with 1uF caps (not the 10uF that you use).
What voltage are you really getting across the coil when it's on?
Bob