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Here are a few tips on  antenna installation and setup for best out put and to help prevent damage to  your radio transceiver or the operator!

SWR stands for STANDING WAVE RATIO  this is the amount of "standing wave" or output energy that starts out from your radio onto your transmission line (or what is commonly called your antenna) ***this is called FORWARD POWER ***and to what ratio of the energy is being reflected BACK INTO your radio ***this is called REFLECTED POWER***which is NOT good. Let me re~state, small amounts of reflected power travelling back into your radio is, in some radio operators opinion, actually good.

This is and has been a pretty contraversial subject for MANY years .

I only want to stress the important part of this phenomenon,protecting your radio!!

Especially your very important (and sometimes expensive to replace) part of your radio,the FINAL OUTPUT DRIVER(S). In modern day radios they are transistors,those black monolith looking components standing on the circuit board inside your radio,usually with three or four legs and attached to a heat sink with cooling fins.These transistors can take may shapes and forms but again,protecting them is the key to a long life for your radio.

Most of these driver and final output transistors in CB RADIOS (the 11 meter band) can withstand quite a bit of abuse from mismatched feedline and antenna setup....up to a point.

  Setting up your antenna for good reception and transmission can be an art  within itself.

First make sure to have the right kind of antenna for the frequencies you plan on transmitting. Most antennas purchased on the market today will come somewhat "pre-tuned" to the proper frequency it is advertised for and will be relatively easy to fine tune your mobile setup with a little knowledge,patience and understanding that,for the most part,is a simple procedure.

There is a saying that has been around radio operators' chat table for years.

It goes something like this:

 "You can have a $4,000.00 radio and a $5.00 antenna and it will have much worse output than a b$4,000.00 antenna and a $5.00 radio" !

So put your investment into your antenna !

Lets take a typical 11 meter (CB) radio, for an example, with a base loaded, magnet mount mobile antenna.

Of course,place your radio where it won't interfere with normal driving or obstruct your vision in any way. It is best practice to attach your +12 Volts and your -12Volts DC directly off of your battery and place your + 12 V fuse within   12" of your source. Use the correct rated fuse ALWAYS. If you have to use a replacement in a fix, use a fuse of a LESS amperage rating. Never use one above the correct rating! In other words, if your radio calls for a 20AMP fuse and you don't have a 20 but you have a 15AMP fuse and a 25 AMP fuse, use the 15 AMP.

Use care not to route your wiring through door hinges or any moving parts of the body or engine.

Route your antenna cable with the same care as you did your power cables until you reach your antenna mount. Since we are using a magnet mount style antenna, place it on or near as you can in the center of your car or truck. This will look good and also provide a good ground plane for your antenna.

Now you should have everything ready to go at your new operating spot in your car/truck. Power cables hooked up with the main fuse removed. Antenna coaxial cable ready to be plugged in but not connected to the radio yet. Microphone connected. Turn your volume control all the way down,your squelch control to the minimum.

For the SWR TEST you will need the following :

 * One SWR meter, some SWR meters are included with the radio! if so,

    GREAT! this test will be even easier. In our example, our radio does not have one,skip down to meter reading section of this guide.

 * One 3 foot coaxial jumper with  SO- 239 connectors on the ends.

         (SO-239 are the typical fasteners used on most CB radios to connect the antenna)

 * the correct hand tool for adjusting the antenna length.

 Look at the base of the antenna or where the wire whip comes out of the coil winding of your antenna,our base loaded example has a small allen wrench set screw holding the whip in place. Check the manual for the antenna if you cannot find it.

 * One black majic marker for marking the whip.

 Connect SWR meter and apply the power to the radio.(remember the fuse).

your test setup should look like this,  RADIO-SWR METER-ANTENNA

 Most every SWR meter will have two jacks on the front or back,side.

They should be labled    ANT.(also RX)    and   RADIO    or XMITTER,XMIT  short for TRANSMITTER .

With radio on your dome lights and any other electrical items OFF,try to sit inside with doors closed if you can.Make sure you are parked away from large power lines,metal objects other cars and away from your house if you have alum. siding!  All of these factors can affect your reading.

Calibrate your SWR meter first by putting your radio on center frequency,Channel 20. Switch SWR to FWD As quickly as possible, pust the Mic.button down and hold.Watch your needle or scale and rotate your calibrate knob until needle goes to CAL. mark on meter,usually all the way into the RED section on the righthand side.

Release the microphone.Your meter is now calibrated to your radio,coax and antenna.

Switch FWD. ~ REF.(reflected) switch to REF. now your meter is ready to show the amount of reflected power coming BACK into your radio.

Go to Channel 1   ONE    push mic. down and hold ,read your meter, note the SWR scale.Should read 1:1  to  1:5   2:1   3:1   let's say we read 1:7 for our example reading.

Go to Channel 40      Push and hold the Mic. down again  and read the SWR on meter scale.  let's say we read  2:5    a little too high

What our goal is to have a reading of 1:5 or LOWER. 

Ideally, we are wanting the lowest SWR reading on Channel 20 or the center of our frequency range we will be using with a higher SWR reading at both,Channel 40 and Channel 1.

The phrase "If it's HIGH ON HIGH, go HIGHER"  will aid in remembering which way to adjust the antenna whip. What this is referring to is the height of our antenna whip. If our SWR reading is HIGH on the HIGHEST frequency or Channel, we need to adjust the whip HIGHER.

Go to the antenna and place a mark with the Black marker onto the whip itself right where the whip goes into the load coil,this will give you a reference point to where your started raising and lowering the antenna whip. losen the whip by freeing up the little allen set screw holding it in place and raise the whip up about one quarter of an inch and re tighten the set screw.

Follow the same steps above and take the readings on Ch.1 and Ch.40  and making any needed adjustments until the SWR reading is 1:5 or lower at any given frequency or channel throughout the operating band you are going to transmit on. 

Worse case, if no matter how you adjust the whip and the SWR is still too high you may have to cut the whip to shorten it,cut small amouts at a time!!! BEFORE you commit to trimming,try moving the car or truck to a different location,check that your radio and antenna base have a good chassis ground and that you have good coaxial cable and connectors ect...It is rare that you will have to trim the whip but it is possible that the factory put too long  or too short of a whip in the antenna when it was made.

Good luck, and have fun with your radio!

And Thanks to all our GREAT customers.

If you have questions, feel free to contact us.

We would be happy to help.

Sincerely,

Chrisc7873               OWNER OF; C3 SPORT AND TOOL