Found in an old Popular Electronics this circuit appears in other variations on this site and in this section. It uses a 7-segment common anode LED display as an indicator.
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...