Antenna System Installation Examples - Do's and Don'ts
We talk with people every day who have issues with their two-way communication systems. We hope this CB World Help Center article will help to give you information on what you should and shouldn't do when installing a two-way antenna system. This could also help you with selecting the right equipment for your particular application.
Two-way antenna systems are different than radio AM/FM, scanner, and short wave systems as you can receive those frequencies with something as basic as a coat hanger or even completely without an antenna! Two-way radio communication, such as CB (citizen's band/11 meter), ham (10 meter), 2 meter, cellular, and marine all require proper installation of an antenna.
Here is some advice when selecting equipment and/or installing a two-way antenna systems:
Overall:
Always check your SWR readings before transmitting with your system. This is VERY important!
Be sure to test for shorts in your antenna system (preferably before installing the equipment). See our other CB World Help Center articles that can help you with testing for continuity.
Antenna:
Remember that the antenna system is just as important (if not more important!) than the radio itself.
Be sure to get an antenna that has the wattage rating needed for your system.
Be sure to select the correct type of antenna for your application.
We do not recommend that you cut off the top of your antenna just so that you can fit into your garage. It is best to but the proper length needed or mount the antenna in a different location.
Mounting Location and Ground:
Ensure that your antenna stud mount is properly installed.
Do not mount ground plane reliant antennas on vehicles without an adequate ground plane.
Be sure to electrically ground antenna mounts for ground plane reliant antennas.
Truck toolboxes are often not sufficiently grounded (electrically). If you are experiencing high SWR readings and your antenna mount is mounted to the toolbox, this might be one of the first things that we would have you check.
Glass mounted antennas are often a last resort recommendation for when other antenna mounts are not available for your application.
Do not mount a glass mounted antenna on windows with deicer circuitry.
Do not sandwich an antenna where the energy cannot escape the antenna. For example, inbetween a pickup window and and a camper.
Try not to install the antenna where the top of the antenna is below the roofline of the vehicle.
For dual or co-phased antennnas, it is ideal to have a line of site between the top portion of the two antennas.
Do not mount antennas close to other antennas as this can affect the performance and how they operate.
Coax:
Low grade coax cable is not recommended for any installation.
Do not use RG59 (75 ohm) coax for single antenna installations. Single antenna installations require 50 ohm coax.
Do not use RG58 (50 ohm) coax for dual antenna installations. Dual antenna installations require 75 ohm coax.
Do not use standard coax with NGP (no ground plane) antennas. You must use NGP coax in a NGP antenna system.
Do not use NGP (no ground plane) coax with a standard antenna. You must use standard coax with a standard antenna system.
For NGP (no ground plane) antenna systems, make sure that the coax is isolated from the mount. Typically, there is a nylon or plastic washer inbetween the NGP eyelet and the antenna mount.
Do not cut or alter NGP (no ground plane) coax. NGP coax is different than standard coax!
Do not splice coax cable as if it were a common 12 volt.
Do not use coax that has the insulation rubbed off.
If you have coax cable that has been potentially pinched in doors, windows, hoods, and trunks, be sure to test continuity and SWR before transmitting.
We hope this helps! Please be sure to look at our other CB World Help Center Articles.