Abstract: A compression amplifier processes both the audio modulating signal to the transmitter, and the audio output from the receiver, in a conventional amplitude modulated transceiver. Unique switching circuitry provides isolation between transmitter and receiver inputs to, and outputs from, the compression amplifier.

Abstract: A resistor is inserted between the audio signal and the primary winding of a conventional modulating transformer used in an amplitude modulated transmitter. The value of the resistor is selected to limit the peak signals into the transformer thereby limiting the peak instantaneous index of modulation to less than 100 percent.A capacitor, coupled to the transformers secondary winding, forms a low pass filter with the impedance of the resistor as transformed by the turns ratio of the transformer. The resulting low pass filter attenuates undesired harmonics.