This circuit was found in RCA documentation from the 90s. It consists of a power control for a load based on a thermocouple. The integrated circuits are uncommon today.
This circuit can be used as a shield as long as the power is supplied with voltage equal to that...
This simple megaphone is from old documentation, but uses still current components. The circuit is...
This simple telephone amplifier can be used as an auxiliary amplifier for additional listening, without...