This is the power supply for the amplifier in the previous circuit. The voltage regulators must be equipped with a heat sink and the transformer is high current.
This small telephone transmitter uses a telephone capsule as a microphone. The L1 coil has 4 to 5...
This circuit was found in an American documentation from the 1980s. The sensitivity ranges from...
This circuit produces a sinusoidal signal whose frequency can be calculated using the formula next...