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 can be used with common transistors, from general purpose to medium power. The...
This configuration can be found in almost all LM117 manufacturer's manuals. This circuit,...
This circuit was published in Popular Electronics from the 90's. The components are common, as...