This old circuit is suitable for signaling applications. The lamp must be incandescent, and the triac must be mounted on a heat sink. The frequency is adjusted in the 1 M trimpot.
Indicated by a Popular Electronics of the 90s originally to measure the light determining the exposure...
Other operational amplifiers series, such as the MC34072, MC34074, MC35071, MC35072, MC35074 d...
Found in American documentation, this circuit shows how to polarize a FET in bootstrap mode. The...