Found in 1969 RCA documentation, this circuit maintains constant current in the filament of a lamp or in a heating element. The circuit makes use of period components.
This circuit can be used for several purposes such as pulse counter, pass counter, roulette, etc....
This circuit is from Radio Electronics. The magazine no more exists, but the circuit can be...
We found this circuit in a French documentation from the 80's. The components used are still...