I've just installed a new CB radio and I'm attempting to "tune" my new firestick antenna. I have the KW2 model that doesn't have the tuneable tip on the top. I'm using the mount that you can get from DMAXALLITECH, and my SWR meter is through the roof. I've already trimmed it 11 times at about 1/4" each. I'm not getting any better readings on the SWR meter.

Can someone tell me if I've cut too much or if I should keep cutting.

:help: thanks!

JT

From the FireStik site:
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HIGH SWR TROUBLESHOOTING

The following list shows the most probable causes of high SWR in order from the most common causes to the least common causes. If experiencing SWR problems, check each of the following conditions in the order shown until problem has been uncovered.

Shorted Stud Mount
Disconnect coaxial cable at antenna mount. Test continuity from mount to antenna coupling nut. There should NOT be any continuity. If shorted, reposition or replace insulators and retest.

Improper Type and Length of Coax
Single antenna installations require RG-58 type coax and dual antennas require the use of RG-59 type coax cables. We recommend 18 foot long coax leads from the radio to each antenna, especially on installations that are displaying high SWR problems.

Shorted Coaxial Cable
Disconnect coax at radio end. Test for continuity between center pin and threaded sleeve. There should NOT be any continuity. If shorted, repair and retest.

No Chassis Ground at Antenna Mount
Test for continuity between the antenna mount and the vehicle's common ground. There MUST be continuity. Repair and retest as required.

Open Coaxial Cable Center Lead
Disconnect coax at radio end. Test for continuity from center pin to antenna base. There MUST be continuity. If necessary, repair and retest.

Open Coaxial Cable Ground Shield
Disconnect coax at radio end. Test for continuity from the antenna mount to the coax connectors threaded sleeve at the radio end of the coax. There MUST be continuity. If necessary, repair and retest.

Improper Installation Location
Transmit antennas need free space around them if expected to perform properly. If more than 30% of the antennas overall length is parallel to the side of the vehicle and within twelve inches of that surface, SWR problems are probable, i.e. between truck cab and shell, corner of truck bed near cab, low mount position on motorhome, etc. Relocate the antenna to a position of performance (versus convenience or appearance) and retest.

Insufficient Ground Plane Available
Fiberglass, plastic and thin aluminum vehicle bodies lack the reflective characteristics needed for proper antenna performance. On some occasions, running a 12ga or heavier wire from the antenna mount to the vehicles chassis ground will be sufficient. Otherwise, a no-ground-plane antenna system may be required.

Low Quality Coax Cable
Delivering radio frequency to an antenna via poor quality coaxial cable is the equivalent of watering your lawn with a hose full of holes. The bitterness of low quality will linger long after the sweetness of low price is gone. Use high quality coax only.

Antenna Tuned Without Tip
If the antenna is tuned without the tip then put on after tuning is completed, the SWR will change when the tip is installed. All readings must be made with the antenna tip in place.

Defective SWR Meter
Some are made bad and others have been known to go bad. Try to confirm readings with a second meter.

Damaged Antenna
Aside from apparent damage that is visible from the antenna striking immovable solid objects, you can test for any internal damage by checking continuity from the antenna base to the tunable tip extender or end of wire. There MUST be continuity. If there is no continuity, the antenna must be repaired or replaced.
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TESTING CONTINUITY

Checking your CB antenna system for continuity, shorts and opens is a MUST process and should always precede SWR checks and settings. Exception: Cable supplied with 'No Ground Plane' antenna kits will have continuity between the center lead and ground.

http://www.firestik.com/images/contnuty.gif

STUD MOUNT PROBLEMS


Beware of poorly designed stud mounts! We are finding that a major cause of lost and broken antennas is due to these stud mounts ... and they aren't just the cheap ones either. Beware of the following problems.

ALUMINUM COMPONENTS: Most people realize that aluminum and stud mounts do not mix. Aluminum studs are structurally weak, don't hold threads very well, and quickly oxidize.

INSULATORS: There are many exotic plastics that will work sufficiently as stud mount insulators. But, for common usage, it is hard to beat nylon from the perspective of quality and cost. There are also many poor choices for insulators and many businesses have found them. When your only decision is based upon cost (material, tooling and process), you will normally find the bad stuff. Cheap insulators use "spongy" material that collapses under torque pressure. When that happens, stud mounts vibrate apart, or their threads get damaged from antenna wobble.

BOLTS & WASHERS: Due to constant exposure to the elements, stud mount hardware should be stainless steel. The stud mount is a very critical connection between the coax and the antenna. Rust and corrosion always hamper performance, and enough of it can cause a dead short. Stud mounts should also have a lock washer, preferably the split lock type. Internal and external star lock washers do not work well against plastic insulators. As the teeth sink into the plastic, the locking tension diminishes and you end up with not much more than a flat washer.

THREAD DEPTH: This is a rarely recognized problem. If the stud has spongy insulators and uses a thin star lock washer, or none at all, the "standard" one-inch bolt that connects the stud to the mount reaches too far into the coupling nut. When the antenna or accessory is installed, the threads bottom out before the component is properly seated. This condition causes load stresses to center on the weakest part of the component, namely, the threads. Most antennas and accessories use a thread length of 1/2" (0.500"). The minimum available thread depth in the stud should be no less than 0.540" (overall length plus one thread width). We measured thread depth on some of the most expensive mounts on the market and found the usable depth to be 0.435". These are problem mounts! Firestik's K-4 stud (installed on a standard mirror mount) has 0.600" of available thread depth and the K-4A has 0.680" available. To eliminate problems, thread depth for Firestik products should be a minimum of...

0.490" for Firestik, Firestik II, and Scanner Antennas
0.570" for FireFly, and Road Pal Antennas
0.550" for Springs and Quick Disconnects
If you are selling or using non-Firestik stud mounts, you should be cautious. Measure their available thread depth. If they come up short, they are causing problems for your customers, your suppliers and/or you yourself. Needless to say, Firestik views this as a very serious problem. Bad stud mounts cause antenna breakage. Dealers that casually make warranty exchanges, or end users that replace broken antennas without checking thread depth may be treating the symptom instead of solving the problem. If the threads are broken, 98% of the time it will be due to bad stud mounts, antennas that were not tightened, antennas that were over tightened, or those that ran into something that they should not have encountered.

Beware of poorly designed stud mounts! We are finding that a major cause of lost and broken antennas is due to these stud mounts ... and they aren't just the cheap ones either. Beware of the following problems.

ALUMINUM COMPONENTS: Most people realize that aluminum and stud mounts do not mix. Aluminum studs are structurally weak, don't hold threads very well, and quickly oxidize.

INSULATORS: There are many exotic plastics that will work sufficiently as stud mount insulators. But, for common usage, it is hard to beat nylon from the perspective of quality and cost. There are also many poor choices for insulators and many businesses have found them. When your only decision is based upon cost (material, tooling and process), you will normally find the bad stuff. Cheap insulators use "spongy" material that collapses under torque pressure. When that happens, stud mounts vibrate apart, or their threads get damaged from antenna wobble.

BOLTS & WASHERS: Due to constant exposure to the elements, stud mount hardware should be stainless steel. The stud mount is a very critical connection between the coax and the antenna. Rust and corrosion always hamper performance, and enough of it can cause a dead short. Stud mounts should also have a lock washer, preferably the split lock type. Internal and external star lock washers do not work well against plastic insulators. As the teeth sink into the plastic, the locking tension diminishes and you end up with not much more than a flat washer.

THREAD DEPTH: This is a rarely recognized problem. If the stud has spongy insulators and uses a thin star lock washer, or none at all, the "standard" one-inch bolt that connects the stud to the mount reaches too far into the coupling nut. When the antenna or accessory is installed, the threads bottom out before the component is properly seated. This condition causes load stresses to center on the weakest part of the component, namely, the threads. Most antennas and accessories use a thread length of 1/2" (0.500"). The minimum available thread depth in the stud should be no less than 0.540" (overall length plus one thread width). We measured thread depth on some of the most expensive mounts on the market and found the usable depth to be 0.435". These are problem mounts! Firestik's K-4 stud (installed on a standard mirror mount) has 0.600" of available thread depth and the K-4A has 0.680" available. To eliminate problems, thread depth for Firestik products should be a minimum of...

0.490" for Firestik, Firestik II, and Scanner Antennas
0.570" for FireFly, and Road Pal Antennas
0.550" for Springs and Quick Disconnects
If you are selling or using non-Firestik stud mounts, you should be cautious. Measure their available thread depth. If they come up short, they are causing problems for your customers, your suppliers and/or you yourself. Needless to say, Firestik views this as a very serious problem. Bad stud mounts cause antenna breakage. Dealers that casually make warranty exchanges, or end users that replace broken antennas without checking thread depth may be treating the symptom instead of solving the problem. If the threads are broken, 98% of the time it will be due to bad stud mounts, antennas that were not tightened, antennas that were over tightened, or those that ran into something that they should not have encountered.

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Tunable Antenna
All CB antennas are tunable in one way or another. Those antennas that have an easy, often mechanical, tuning device are referred to as a "tunable antenna". Accordingly, lots of people think the other antennas are not tunable and so they make no attempt to have the antenna tuned. This is a critical mistake.

Wire-wound antennas without mechanical tuners, that test electrically long, can be tuned by removing wire from the top. If SWR testing indicates the antenna is electrically short, the coils at the top of the antenna can be separated and spaced further apart or accessories that increase the physical length of the antennas (springs, quick disconnects) can be added.

Solid fiberglass antennas (straight or helical wire impregnated in fiberglass resins) that are electrically too long can have the cap removed and the top can be cut off with a hacksaw. If the SWR test on one of these antennas indicates that it is electrically short, the addition of a spring or quick disconnect (or both) is the only way to correct for the short condition.

Base loaded antennas with wire whips have a set screw (or two) just below the area that the whip is inserted into the loading coil. By loosening up the set screw(s) you are able to slide the whip up or down as required.
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If the SWR on channel 40 is greater than that on channel 1, your antenna is considered to be "LONG" and reduction of physical height and/or conductor length will correct this situation. Depending upon antenna model, this entails screwing down the tunable tip (Illustration #1: Firestik II, Firefly), or, removing the tip, making short slits in the plastic covering and unwinding and clipping off wire (Illustration #2: Firestik, Road Pal). Firestik Designer Series antennas require loosening the allen screws and lowering the metal whip (Illustration #3).
http://www.firestik.com/images/tuning2.gif

ADJUSTING SHORT ANTENNAS

If SWR on channel 1 is greater than that on channel 40, your antenna is considered to be "SHORT" and increasing the physical and/or electrical length of the antenna is required to correct this situation. Because we make our antennas extra long, readings which indicate "Short" normally stem from ground plane deficiency (lack of vehicle metal surface for the antenna to reflect its signal rom). This condition is often corrected by adding a spring and/or quick disconnect to increase the physical height. Ground plane deficiencies can also be compensated for by using dual (co-phased) antennas or special no-ground-plane antenna kits.

Lengthening of the Firestik II and Firefly is accomplished by turning the tuning screw further out (Illustration #1). On Firestik and Road Pal models, it requires tip removal, short slits in the plastic covering and, the separation and upward repositioning of three or more wire turns (Illustration #4). Firestik Designer Series antennas require loosening the allen screws and raising the metal whip (Illustration #3).

NOTE: The shorter the antenna, the more sensitive it is to adjustments. For example, removing two wire turns on a 4 foot antenna might move the SWR by 0.3; the same amount
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Thanks, I had seen that page, but I guess I hadn't read that far down. It looks like I mangled that antenna pretty good, sCensoredt. Oh well, you live, you learn.

JT