This circuit responds to frequencies from 100 Hz to 3 MHz. We find it in a 90s Radio Electronics. Transistors are general purpose types.
We found this circuit in the magazine Eletcronics Now of July 1994. The power supply is according to...
This simple circuit produces a tone when triggered by any vibration picked up by the sensor. The...
In the figure we show how two diodes can be used to simulate the center tap of a push-pull driver step....