Slave flash trigger - using solar cells

slave flash trigger A triggering circuit for slave flash guns ensures that the "slave", flashes simul- eye. taneously with the main or master gun. Apart from the commercially available units, there are quite a few circuit designs published in electronic magazines. Unfortunately most of these have one major drawback. They all need some form of power supply, such as normal batteries etc. The circuit design described in this article uses a virtually in-exhaustable supply! Solar cells are applied here in an ingenious way! The flash of light 3mitted by the master gun will trigger the slave. The small delay which occurs is so small (in the order of 1/1000th of a second), that it is The circuit consists of a sensitive low powered thyristor, in this case the TIC 106D (Th1), and a choke. The solar cells (which should have a minimum surface area of 100 mm 2) are connected in series. They generate the ignition pulse for the thyristor immediately the master flash is fired. A 68 mH choke ensur...