We found this transistorized circuit in a 1985 documentation. The circuit can operate with voltages from 9 to 12 V and the adjustment of the operating point or input sensitivity is done in P1.
This circuit works only with carbon microphones, due its low impedance. The speaker should be good or...
This circuit produces a sinusoidal signal whose frequency can be calculated using the formula next...
This circuit was found in the 1987 Radio Electronics magazine. The components used are integrated...