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Old 01-17-2014, 04:38 PM   #1
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High SWR when tuning new/shorter antenna

I've been running a 3' antenna for a bit now, but as it won't fit in the garage, I've knocked it off a few times when I forgot to remove it when pulling into the garage. As my mount is kinda high, I bought a 2' that I could run that would allow me to park in the garage without removing it.

I just finished attempting to tune it and found the SWR to be in the red on all channels. I tested the coax and it seemed fine. I then retested my 3' anntena and it was still fine.

I turned the tuning screw out on the 2' antenna about an inch but that seemed to have no affect.

Any suggestions?

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Old 01-17-2014, 05:17 PM   #2
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Are BOTH nylon washers on the mount?
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Old 01-17-2014, 05:42 PM   #3
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Quote:
Originally Posted by Sinister6 View Post
Are BOTH nylon washers on the mount?
I'm using a fire ring coax so it doesn't use both. Simply unscrewed the 3' and screwed on the 2'. 3' is fine. 2' is in the red on all channels.
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Old 01-17-2014, 06:35 PM   #4
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Ok, try putting the 3' back on and see if SWR goes back lower levels. Maybe you got a bad antennae?
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Old 01-17-2014, 06:43 PM   #5
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Quote:
Originally Posted by Sinister6 View Post
Ok, try putting the 3' back on and see if SWR goes back lower levels. Maybe you got a bad antennae?
Read my post again. Already did that.

No joy.
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Old 01-17-2014, 06:55 PM   #6
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what about a quick disconnect and keep your 3'?? That's what I did... Hope you figure you it out.
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Old 01-17-2014, 07:05 PM   #7
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Quote:
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what about a quick disconnect and keep your 3'?? That's what I did... Hope you figure you it out.
Thanks. I have a quick disco for my 3' but I kept forgetting to take it down when pulling into the garage. Almost snapped the antenna a few times. LOL
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Old 01-17-2014, 07:14 PM   #8
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Quote:
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Thanks. I have a quick disco for my 3' but I kept forgetting to take it down when pulling into the garage. Almost snapped the antenna a few times. LOL
LOL been there! I added a HEAVY DUTY spring to my set-up gives me a little forgiveness...
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Old 01-17-2014, 08:14 PM   #9
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LOL been there! I added a HEAVY DUTY spring to my set-up gives me a little forgiveness...
I have a spring but didn't like it. To much wagging for my liking on the trail.
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Old 01-17-2014, 08:18 PM   #10
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There is nothing wrong with the 2ft antenna. You just need a 3ft antenna to get the better SWR reading. A 2ft antenna would work if you placed it higher on the Jeep. The 2ft antenna is just not getting the proper clearance around the Jeep as the 3ft. If you went to a 4ft antenna the SWR would be even better.

Try putting on a 3in spring on the antenna. At least you won't break the antenna off.
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Old 01-17-2014, 08:58 PM   #11
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I'm not sure what spring you had but I use this one and I may get a VERY little movement but it stops almost immediately.
Amazon.com: Firestik SS-3H Heavy Duty Stainless Steel Antenna Spring: Car Electronics
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Old 01-17-2014, 08:59 PM   #12
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Quote:
Originally Posted by Sinister6 View Post
I'm not sure what spring you had but I use this one and I may get a VERY little movement but it stops almost immediately. Amazon.com: Firestik SS-3H Heavy Duty Stainless Steel Antenna Spring: Car Electronics
I'll check. Thanks.
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Old 01-22-2014, 09:22 PM   #13
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I tried to use a 3footer with a mount bracket on the rear tire. Couldn't get a decent swr so I called firestik. The tech told me that it is really difficult on a Jeep and was good enough to let me swap for a 4footer. Swr's are great but I hate having to leave my antenna off unless on a trail or a road trip.

I hate where it is mounted and need to consider moving it.
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Old 01-23-2014, 04:10 PM   #14
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Get a quick disconnect for it. I'm putting a 4 footer on my wrangler with a quick disconnect so it fits in my garage. Soon as it warms up that is!
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Old 01-27-2014, 09:40 AM   #15
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You don't need a longer antenna to get a better SWR, you simply need to find and fix the reason for your higher SWR. My 2' Firestick has a 1.1:1 SWR so don't feel it's strictly because of its length. The "sweet spot" on the length adjustment is narrower with shorter antennas so it can be missed which means you need to make smaller adjustments between SWR checks.

Sinister6, your mount should not have that second washer underneath the mount as shown in your photo. That side of the mount called the SO-239 Coax Connector (as shown below) must be grounded to the frame, not insulated.

It should look like the below illustration. That the SO-239 Coax Connector part of the mount is not insulated and actually requires a bare metal connection to the mounting bracket is how the antenna picks up its required ground connection which provides the antenna's ground plane connection.
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