We found this circuit in a 1956 Sylvania publication. It serves to monitor telegraph transmissions being placed next to the transmitter. The circuit is indicated for the range of 80 and 160 meters.
May 2017 - Panasonic's new APS1 series of optical couplers with 3 750 V insulation and up to 50...
This circuit can detect both light and shadow using an LDR as a sensor. We found the circuit in an...
This simple megaphone is from old documentation, but uses still current components. The circuit is...