This 4-waveband converter circuit was found in Radio Craft September 1948. The power supply is not given, but the supply voltages are indicated.
This circuit is from the SGS manual of linear integrated circuits of 1982. The L78xx is equivalent to...
This low displacement circuit was found in American documentation from the 90s. Operational...
The purpose of this circuit is to maintain the liquid level of a reservoir between two values...