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Discussion Starter #1
Hey guys,

just checked my SWR on my radio its at about 1.8/1.9 - the tuning screw at the top of my 4" firestick is out as far as it will go (screwed further in brings the SWR up).


I really don't want to go any longer on the antenna, looks stupid.

Could a shorter antenna be a solution also to get below that "wave" thats bouncing back?

The antenna has good ground, i mean its mounted right to the backrack w/ 4 metal screws, though maybe thats not good Enough??

Any other solutions??


Always appreciate the help guys.
 

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What is your SWR on Ch 1 and Ch 40? That will tell you if the antenna is dialed in or not.

What SWR meter are you using?

Is the antenna mounted to the top of the backrack or is the base bed height?

What type of coax do you have running between the radio and the antenna? Any coils in the coax anywhere?

Adding a separate ground from the body to the mount would be a quick way to see if you have a grounding issue, but I don't think this is the case. But you do want to try and rule that out as a possible issue.
 

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As Showstop said what are your numbers at on ch. 1 and 40

I had the same issue with mine and the added ground (12ga) helped out nicely
 

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Discussion Starter #4
Ch. 1 swr is at 1.9
Ch. 40 swr is at 3.0

ch. 19 is like 2.4ish (terrible)
 

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Ch. 1 swr is at 1.9
Ch. 40 swr is at 3.0

ch. 19 is like 2.4ish (terrible)
Your antenna is too long. Turn the adjuster down to bring down the SWR on the higher channels.

Overall, the SWR numbers are too high. If you can answer some of my other questions, that might help narrow down the cause of the problem.
 

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Discussion Starter #6
What is your SWR on Ch 1 and Ch 40? That will tell you if the antenna is dialed in or not.

What SWR meter are you using?

Is the antenna mounted to the top of the backrack or is the base bed height?

What type of coax do you have running between the radio and the antenna? Any coils in the coax anywhere?

Adding a separate ground from the body to the mount would be a quick way to see if you have a grounding issue, but I don't think this is the case. But you do want to try and rule that out as a possible issue.
Antenna is mounted to the lowest crossbeam, the square one that mounts to the truck.

SWR Meter is an ASTATIC

theres definitely a coiled section man, cant actually remember what i did when i ran it a year ago, 3 loops at the most.
 

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Discussion Starter #7
Your antenna is too long. Turn the adjuster down to bring down the SWR on the higher channels.

Overall, the SWR numbers are too high. If you can answer some of my other questions, that might help narrow down the cause of the problem.

if i turn the tuning screw in farther the SWR Climbs across ALL the channels
 

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Discussion Starter #8
so if the antenna is 4ft. now... 3ft? 2ft. is probably TOO short?
 

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The Firestiks are pre-tuned, regardless of the length. So the length of the antenna isn't the issue. Get rid of those coils in the cable. That causes problems. What length is the coax and is it just a pre-assembled cable? Did you pinch it in a door or window anywhere?

Add an extra ground lead to the mount to see if that helps. Check to see if your antenna is grounding to the mount. You will need a multimeter to test this.

If you have the ability, re-locate the mount to the back of the bed and see if that helps. Maybe the rack is reflecting too much of the signal.
 

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no

Firestiks aren't pre tuned, they use 'x' amount of wire coiled around a fiberglass mast and yadda yadda...it's on their site.

I just installed my 5' firestik and had to troubleshoot high SWR on mine, originally a bad ground because the mount wasn't assembled properly, I had the nylon part of the mount in the wrong location shorting the antenna out.

Double check your installation, you don't want loops in your cable anywhere, just bundle them them, don't run them anywhere there might be higher current wiring already.

Read some of this...we aren't there and though we could help, it will take less time if you if just read over the install suggestions and look at it yourself. It took me two attempts at installing mine and it is on the front bumper and I can transmit and receive clearly within several miles

http://firestik.com/Tech_Docs.htm

Brandon
 

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Firestiks aren't pre tuned, they use 'x' amount of wire coiled around a fiberglass mast and yadda yadda...it's on their site.
You misunderstood what I said. The OP was thinking he needed to cut down the antenna or get a different size. In the older antenna designs, and some current base loaded designs, the intent is to cut the length of the antenna mast to adjust the SWR. Top loaded fiberglass antennas like the Firestik are tuned for a specific frequency band. In the case of the Firestik II, the tuneable tip is for fine tuning the center point of the band you intend to use it on. This holds true for all their antennas, regardless of length. So the length is not the issue in this case.
 

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Thanks for the link. Lots of great info.

37. One of the greatest benefits of the FS series (patented tunable tip) antenna is noted when there is lack of available ground plane. If the tuning screw reaches its "maximum out" position before satisfactory SWR is realized, a common 1/4-20 threaded bolt or screw of a longer length can be used to replace the supplied tuning screw. If the vinyl cap is too short to remain in place, the user can disregard it or clip a hole in the top for the longer screw to pass through.
 

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Discussion Starter #13
Thanks for the link. Lots of great info.

hmmmm adding a longer screw might be a good bandaide for now until i can really address the problem...


i was thinking last night i need a better ground than the backrack, since 90% of the rack is VERTICAL, right along side the antenna haha, thinking of getting a grounding strap or large guage wire and running it to one of the bed bolts or tie-down points.

thoughts?
 

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Discussion Starter #14
just made a crazy discovery....

when i take the little firestick cap off the top of the antenna my SWR at ch. 19 goes from 2.5 down to 1.8/1.9


sooo weird


guess i'm leavin' the cap off

also gonna see if i can ground her out a little better maybe get it down to 1.5 or maybe even 1 watt! :xpimp: haha
 

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just made a crazy discovery....

when i take the little firestick cap off the top of the antenna my SWR at ch. 19 goes from 2.5 down to 1.8/1.9


sooo weird


guess i'm leavin' the cap off

also gonna see if i can ground her out a little better maybe get it down to 1.5 or maybe even 1 watt! :xpimp: haha
You do know that SWR is a ratio.. there is no units.... and that you'll never get to 1; you might get close (and that is the goal), but you'll never get to 1:1; if your equipment says you are at 1:1, it's inaccurate. Good Luck. Have Fun. :D
 

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Discussion Starter #16
You do know that SWR is a ratio.. there is no units.... and that you'll never get to 1; you might get close (and that is the goal), but you'll never get to 1:1; if your equipment says you are at 1:1, it's inaccurate. Good Luck. Have Fun. :D

yeahh, i understand guess i knew that, but couldnt articulate it haha


thanks man.


you got any suggestions tho??
 
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