Modulation transformer
Encyclopedia
A modulation transformer is an audio-frequency transformer
that forms a major part of most AM
transmitters. The primary winding of a modulation transformer is fed by an audio amplifier that has about 1/2 of the rated input power of the transmitter's final amplifier stage. The secondary winding is in series with the power supply of that final radio-frequency amplifier stage, thereby lowering and raising the operating voltage of the power amplifier (PA) tube or transistor. Considering that the PA device is operated as a class-C amplifier, i.e. as a switch, the modulation transformer is responsible for the amplitude modulation (AM) of the transmitter.
Transformer
A transformer is a device that transfers electrical energy from one circuit to another through inductively coupled conductors—the transformer's coils. A varying current in the first or primary winding creates a varying magnetic flux in the transformer's core and thus a varying magnetic field...
that forms a major part of most AM
Amplitude modulation
Amplitude modulation is a technique used in electronic communication, most commonly for transmitting information via a radio carrier wave. AM works by varying the strength of the transmitted signal in relation to the information being sent...
transmitters. The primary winding of a modulation transformer is fed by an audio amplifier that has about 1/2 of the rated input power of the transmitter's final amplifier stage. The secondary winding is in series with the power supply of that final radio-frequency amplifier stage, thereby lowering and raising the operating voltage of the power amplifier (PA) tube or transistor. Considering that the PA device is operated as a class-C amplifier, i.e. as a switch, the modulation transformer is responsible for the amplitude modulation (AM) of the transmitter.