rudy__
Opt-Trig-Sch
This optical trigger was designed for flash units with low voltage trigger voltages. I have used it with trigger voltages of 6 volts and with some flashes with a trigger voltage of 4 volts.
Optical trigger schematic. Q1 is a photo-transistor that I pulled from old floppy disk drives. I have used small pulse transformers for L1.
None of the parts are critical.
Q1, L1 and Q2 do the initial triggering. The rest of the parts hold the output on and will stretch very short pulses.
Opt-Trig-Sch
This optical trigger was designed for flash units with low voltage trigger voltages. I have used it with trigger voltages of 6 volts and with some flashes with a trigger voltage of 4 volts.
Optical trigger schematic. Q1 is a photo-transistor that I pulled from old floppy disk drives. I have used small pulse transformers for L1.
None of the parts are critical.
Q1, L1 and Q2 do the initial triggering. The rest of the parts hold the output on and will stretch very short pulses.