SWR 'Contest'

SSTJ

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Since many of us have such similar setups, I'm wondering if we can compare SWR results. I'm using a Uniden 520XL with a 2' tune-able Firestik antenna, which is mounted above the driver's side tail light. I can't get my SWR below 2.4.

Any others with a similar setup, I'm eager to hear your results. Let's not use this thread to troubleshoot each other's setups, I'm just wondering how much the minor differences in our rigs might affect our individual results.

Update: @Jerry Bransford has this same setup and has SWR levels around 1.5, so it must be possible ...
Update: Finally got it under 1.4 on Channels 1 & 40, and under 1.2 on Channel 20.
 
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I was able to get it under two, all I remember doing was dicking around with the tip of the antenna & getting a better ground on the tub. Both sides, took it down to metal the entire circumference of the washers, sealed over it.
 
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1.4 on 1 and 40. Kept having to make it longer then put the tip on the Firestik and had to make the antenna shorter again. I really did not believe that little rubber cap would make a difference until I saw it with my own eyes.
 
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On a 520 as well, with a 3' Firestick... About 1.6 at last check. Took a bunch of tinkering and even going to a premium antenna cable. Before that, I was struggling to get below 2.
 
First ensure the antenna mount is grounded REALLY well to the vehicle frame, the coax and antenna are in good condition.
When taking SWR readings make sure the vehicle is at least 10' from any metal objects that the radio TX can reflect against.
There is no reason why you shouldn't be able to get SWR down to 1.5 at 26.965 and 27.405.
 
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On a 520 as well, with a 3' Firestick... About 1.6 at last check. Took a bunch of tinkering and even going to a premium antenna cable. Before that, I was struggling to get below 2.
Can you say more about the cable? I’m curious.
 
1.8-1.9 with Uniden 520 and firestick 5 foot on a spring. I had to actually make the antenna *longer* with a longer bolt in the tip to get it down. Probably has to do with the spring - I need to play with it some more...
 
Most times the coax that is used by the mobile CB antenna manufacturers is RG-58 (18') due to its diameter and flexibility.
The 18' length can sometimes be trimmed to optimize SWR, but for the low wattage that CBs transmit at; a better coax such as LMR 240 is not really needed until you move past 100W.
Just focus on the chassis grounding issues and you should have no problem achieving a SWR of 1.5 and lower.
 
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Can you say more about the cable? I’m curious.
Sure, link below... but it’s entirely possible that my economy cable was defective.

As above, I also worked with a sanding drum to get to bare metal on the antenna mount and tub.
Cable Experts RG-8X Coax Cable - 18 FT PL259 M/M Connectors - Heavy Duty Indoor/Outdoor Weatherproof Jumper Cables - CB, Ham Radio, Short Wave Radio - HF, VHF, UHF https://www.amazon.com/dp/B07V5WRRM6/?tag=wranglerorg-20
 
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I was able to get it under two, all I remember doing was dicking around with the tip of the antenna & getting a better ground on the tub. Both sides, took it down to metal the entire circumference of the washers, sealed over it.
Cool. What length antenna?
 
Cool. What length antenna?
That would depend upon where you are going to mount the antenna, but since you are mounting the antenna in the rear passenger side corner you will be directional with your TX/RX. You would make sure the antenna you are mounting is a stainless whip design at a minimum of 36" to clear the roof line.
 
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I went with the 4' firestick with a uniden 510. I struggled tuning it and finally took it to a shop that specializes in radios. He checked my set-up out, told me my SWR meter from amazon was junk and then tuned me down to around 1.1. All I did for that excellent experiece is make a purchase (bought an external speaker) and ask the question...he did the troubleshooting and tuning for free.
 
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Interestingly, I had purchased a 2 foot "trail use" antenna a couple of weeks back at the local ham radio store. The old timer there told me that it was "the only 2 footer that actually works". Its a "ProComm" stainless steel whip, it has two metal rings near its base to tune it with. For whatever its worth, much to my surprise it has REALLY good SWR and was very easy to tune - 1:1 on channel 1, about 1.1:1 on 19, but then it goes up to about 2.2 on 40 (couldn't get it lower on 40, but I could raise it on 1!). Now how well it "gets out" is a completely different question, it could be a dummy load for all I know! Time will tell - couldn't raise anybody here at the house, but that's not unusual. Of course, it won't be as good as the 5 foot Firestik by any means, but should be fine for the trail at least.

ProComm 2 foot:
DSC00546.jpg


5 foot FireStik:
190.jpg
 
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Thanks all. Anyone else out there running my exact setup by chance? Uniden 520XL and Firestik 2’ on a tail-light mount?