Found in an Electronic Design from the 90s, this circuit measures the phase difference between two signals using an electronic multimeter. The circuit makes use of components of the time.
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...