triac control board - controls eight mains lamps

The circuit described here is a triac-controlled mains lamp firing circuit consisting of eight independent channels. Each channel contains an opto-isolator to maintain complete isolation between the control circuit and the mains power supply. The board was primarily designed for use with the "programmable disco light display" published in the February 1984 edition of Elektor, but it has many more applications. It will, for in- stance, be ideal for use as an interface between the I/O outputs of a com- d. puter and mains powered equip- ment. It can also be used to ex- pand existing circuits which have only an LED display. ,0 The cir- cuit consists of eight channels on one printed- circuit board each of which is a self-contained mains lamp firing circuit. Complete iso- lation between any control circuit and the mains supply is ensured by the use of opto-isolators. This also means that the cir- cuit can be used with any other control system that is ca- pable of driving an LED. control...