In fact, this circuit from the 60's applies to photographic printers of the time, timing the lighting of a 20 W lamp. The components are from the period.
This circuit of a few tens of milliwatts of power requires a single source. We found it in a Radio...
This circuit is suggested by Texas Instruments in his Optoelectronics Sourcebook. The transistors...
This circuit used in signaling for boats, cars or barriers was found in a 1980s documentation. It still...