Race Communications: How to Properly Mount an Antenna

Features, Racing I By Jeff Sexton I February 27, 2020

Mounting your antenna properly determines the range and clarity of your two-way radios. A bad coaxial cable or an improperly mounted antenna can restrict two-way radio range from miles to feet.

Location:

Proper antenna location ensures you’re reaching the full range of your communications system.

When selecting location:

Antennas radiate best in the center of the roof of a vehicle, because the metal roof of the vehicle acts as the best ground plane (for non-metal roofs, a ground plane will be added on the inside of the car just under the roof)
Cars without a roof you may opt to install on the rear quarter panels to avoid interfering with the opening and closing of the trunk (See picture B)
Consider your wiring route for best antenna mount position (See picture A,C, antenna is mounted in center of roof before the rear glass so that the wiring can follow the roll bar designed into the car)

Cable Routing:

Proper cable routing is key to a noise free system and ensure your communications system will operate properly.

When routing your coax:

Do not coil up excess wire
Run your coax as short as possible
If you have a small amount of excess, route it under a seat or along a roll bar to prevent coiling excess cable
Do not route near heat
Do not route near ignition systems
Do not run radio coax and intercom helmet cables in the same wire loom
Avoid pinching
Careful not to over tighten with zip ties

Proper Ground:

Improperly grounded antennas can radiate on the outside of the coax and introduce RF radiation into other components of the vehicle or create radio static.

When mounting:

Ensure the brass teeth of the antenna mount are pressed together on a flat surface with either the bare metal roof or ground plane plate designed to act as the ground
Ensure the upper brass antenna mount is tightened snug on the exterior of the car