Found in an Australian documentation from 1991, this circuit was sold in a kit at the time. It is a small FM transmitter with a very common configuration, also found in other projects on this site.
Found in an Electronic Design from the 90's, this circuit uses common components. The circuit is...
When the sensor receives light, the relay closes its contacts and remains so even after the light...
This circuit produces pulses of 90 V at intervals that can reach 5 minutes. The circuit is from a...