This circuit was found in the July 1992 issue of Radio Electronics magazine. The circuit is based on a 741 that activates a buzzer with oscillator. R5 adjusts the sensitivity.
Standing wave ratio or SWR is an important measure of whether all power from a transmitter is being...
Here we show how to add a reset key to the monostable using two NAND gates (CB127E). When the key...
This short-range circuit can act as a wireless microphone. We got the schematic and the printed...