Found in Electronics now from the 90s, this circuit uses a sensor from the time, which is difficult to find today. The circuit activates a sonalert-type buzzer.
The coil and sockets of this circuit found in a QST depend on the frequency band that is intended...
Indicated for discriminators adjustment in FM and VHF receivers, this circuit was found in a 90s...
Mouser Electronics is making available the Texas Instruments DRV401 Q1 integrated circuit, a...