The COMNAV-Module

This module can be found in absolutely every Aircraft - it is essential for both communication and navigation.

Here's a picture of a Bendix-King Com/Nav-radio found in a Cessna 172 (screenshot taken from the 2D-panel of FS9's default C172)

It mainly consists of two parts, one for COMmunication and one for NAVigation (as already mentioned). Usually, as on the picture above, the left half of the module is the COM- and the right half the NAV-part.

Each of these parts has
- two displays with 5 digits each
- one pushbutton and
- a rotary encoder.

The left display of each part shows the "active" frequency the radio is actually tuned to (above it's 118.20 for the COM- and 110.30 for the NAV-part)

The rotary switch is used to tune the "standby" freqency, which is shown in the right display, respectively. Once the desired frequency is dialed into the "standby"-display, the <-> toggle pushbutton is used to swap the active and the standby-frequency.