Using SCRs, this circuit from a 1967 General Electric manual allows full wave load control with SCRs. SCRs can be modern types depending on the load.
This narrowband data receiver is from the Philips Databook of 1990. The circuit is powered by 5 V...
This circuit was proposed by an old American documentation for listening to SSB stations. The...
This voltmeter for continuous voltages has several scales and is totally passive. The diodes are...