The volume control is a diode attenuator placed at the output of the MMIC.

An MMIC (Monolithic Microwave Integrated Circuit) amplifier is used to bring up signal power. The output is connected to a diode, used as a variable attenuator.

This attenuator passes excess power to the ground so that the next stage of the receiver is not overloaded. A comfortable listening level is set with this control.

The amount of signal passed to ground is determined by the amount of current going through the diode. When no current is going through the diode, all the signal passes through the attenuator. As current is increased through the diode, some of the signal goes to ground.

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Last Update: 11-23-2002
Web Author: David White, WN5Y