This circuit was obtained from a 1965 Radio Electronics. The semiconductors used admit modern equivalents. The high voltage coil is an automobile ignition coil.
We found this alarm in a 1992 documentation. The circuit has several timings and the relay can...
This transmitter is modulates a infrared light source from an audio signal. Applications include a...
We found this configuration in an integrated circuits manual. The transistor, which can be of any...