Found in a 1967 Ferranti documentation, this circuit uses a LDR from that time as a sensor. Transistors can be replaced with modern equivalents.
Found in American documentation from the 90s, this circuit uses components that are still common...
We found this circuit in the June 1991 issue of Radio Electronics magazine. The integrated circuit is...
When more current from a digital output is needed than a single output could source or drain, a...