Q The antenna I bought claims to be pre-tuned. Do I need to do anything?
A Yes. You must tune your antenna to your vehicle. The antenna is pre-tuned on a test
bench to make certain it is within the general frequency specifications. It will be somewhat different on your vehicle
because of the difference in the ground plane and surroundings. Always check your antenna ... even if you move it from one
location on your vehicle to another.
Q Can I use any kind of wire to hook my antenna to my radio?
A No! For single antenna installations we recommend RG-58 A/U type coaxial cable. If you
are running dual antennas (co-phased) you must use RG-59 A/U type coax. Make sure you buy the best cable too. We see
numerous problems caused by low grade coax. Don't cut corners when it comes to coax.
Q Is the length of the coax cable important?
A We find that it is very important ... especially with high performance top-loaded
antennas. Your safest bet is to use 18 feet (5.5 meters) coaxial leads on all of your CB installations.
Q I only needed 9 feet of coax to go from my radio to my antenna. How should I handle
the excess?
A What ever you do, do not roll it into a small convenient coil. It will become an
RF choke. If you cannot let it lie loose under a seat or in a headliner, wrap it into a yarn-like skein of about 12 to 16
inches, put a wire tie in the center and tuck it under your dash, seat, etc.
Q My system has very high SWR, but I only talk very short distances. Since distance isn't
important, should I be concerned about high SWR?
A Absolutely! High SWR will limits distance and may cause serious damage to your
transmitter. The time spent tuning your antenna is time well spent. Don't take the chance.
Q What is are the most common errors you find on CB installations?
A In order of most to least common, 1) antenna not tuned to vehicle, 2) mounting
locations chosen for convenience or appearance versus effectiveness, 3) coax cable ... low quality, worn out, wrong
length, or severely pinched, 4) standard antennas used on vehicle with no ground plane instead of special no-ground-plane
system.
Q There are a lot of different antennas available for CB. Are some better than
others?
A Without a doubt, top loaded antennas are better than center loaded antennas, and
center loaded antenna are better than base loaded antennas. Also, within each style, the taller the antenna the better
it will generally perform.
Q How important is it to have the antenna mount grounded to the vehicle?
A Unless you are using a no-ground plane system, it is extremely important. Ungrounded mounts will
usually cause SWR to be high across all channels.
Q I am using a Firestik no-ground plane (NGP) antenna system and the mirror arm I mounted
it to is grounded to the vehicle. Do I need to insulate it?
A No! We already took care of that with the design. The NGP systems will operate the
same regardless of whether or not the mount is grounded.
Q I have a couple of different antennas and I've noticed that there are times when one works
better over long distances than the other. However, it isn't consistent, Why is this happening?
A Every antenna design has a different angle of radiation and it stays pretty constant
unless the antenna is moved. What keeps changing is the ionosphere height. Your signal is bouncing off of the ionosphere and
the varying height of it changes the angle at which the signal bounces back to earth. You have no control over this. An
antenna might work long distances on one day, and not the next.
Q I've tried to find some books that will teach me how to set my SWR, process coax
connectors and offer some tips on antenna installations. Most of what I've seen is pointed towards the engineer or technician. Do you know where I can find some help that is written in layman terms?
A We know the problem. Firestik wrote a simple book titled "Measuring SWR and Things
Every CB'er Should Know" to help you better understand antenna installations.
See the Technical Help page for complete information on the booklet.
For additional technical information, visit our technical library.
Updated: 2023.12.05
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