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Discussion Starter · #1 ·
INstalled my CB this weekend ( Cobra 75WXST ) and started tuning it, the lowest i can get a SWR signal is 2.3- 2.5 on 1 and 40 . I have a good ground ( grinded the hell out of mount and FJ ) Am i ok, or should i change something ? Cable ? Antenna ( it's a 3 feet Firestick ) ?
 

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Discussion Starter · #3 ·
Mounted on the back door with a Bandi mount
 

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Discussion Starter · #5 ·
Would a longer antenna help ? 4-5 feet ?
 

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Check your grounding. Make sure you have star washers between the mount and the body and that you cleaned off some of the paint on both. %99 of SWR issues are because of poor grounding. I helped a member tune his on a similar mount from boztec and a firestick to dead on 1:1 on channel 19.
 

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If you have someone else with an FJ try their antenna on your mount for SWR and visa-versa. That could help to pinpoint the potential problem. Also make sure that you have that cap on the antenna when you check the SWR. Make sure that the doors are closed too. Sometimes, i don't know why, but having a door open, or leaning in the car will sometimes screw with the SWR of the antenna. Check your PL-259 antenna connector also for a bad shield contact.
I've had a bad connector cause poor SWR's before.
You should be able to get it better than 2.3-2.5 to 1.

KyFJGuy
 

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i have the same radio and yes going to the longer antenna (4 foot) firestik worked for me my swr now is around 1
 

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Would a longer antenna help ? 4-5 feet ?
A longer antenna will help your range, but not necessarily the SWR. The ground plane (not the same thing as having the antenna electrically grounded) required by a given antenna depends more on the frequency-wavelength of the antenna than the physical length. Because most antennas have a lot of wire coiled around a fiberglass mast or in a base coil under a metal whip, you can't assume or even measure the wavelength without consulting the manufacturer. A 1/2-wave antenna is much more forgiving of poor ground plane than almost any other.

If you put your antenna on your hood or your roof, you would have a much better ground plane than on a bumper or a Bandi mount, and could run almost any antenna out there and get it to tune-up acceptable SWR. But not many of us want to do that, mostly for clearance issues. So we mount them on a bumper or a Bandi-mount, but then you have to accept some compromises in both the antenna that you can use (due to lack of ground plane) and performance. For most of us that only use our CB's on a trail run with other trucks close by, this is an acceptable compromise.
 

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Discussion Starter · #10 ·
Thanks for the explanation 1911 , now i understand the plane thing
 

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Rookie question here:

With antennae quick disconnects.... do you have to worry about tuning every time you connect and reconnect?

Thanks,
:cheers:
 

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A longer antenna may help. It helped me. With a 2' Firestik, I had about the same SWR as you. With a 4' Wilson Flexible I got it down to 1.5.

The ground plane may be an issue but I think equally important with a Bandi mount is the amount of metal close to and running roughly parallel with the antenna. The more antenna you can get away from all that reflecting metal, the better off you'll be.
 

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INstalled my CB this weekend ( Cobra 75WXST ) and started tuning it, the lowest i can get a SWR signal is 2.3- 2.5 on 1 and 40 . I have a good ground ( grinded the hell out of mount and FJ ) Am i ok, or should i change something ? Cable ? Antenna ( it's a 3 feet Firestick ) ?
Don't except comments that a 3' Firestik is not good enough. I have a 3' Firestik mounted in back by the door hinge and my SWR is 1.2, flat all the way between 1 and 40. I'm using a Firestik Fire-ring cable. The mount is screwed into the metal right next to the door hinge so the ground is no problem. With a Galaxy CB I've talked 10+ miles while still in my garage.
 

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Rookie question here:

With antennae quick disconnects.... do you have to worry about tuning every time you connect and reconnect?

Thanks,
:cheers:
Nope. Should be good every time.
 

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Meters can vary a bit too. You could just try talking to people and find out how far away they are. If you can talk to people 2-3 miles away reliably, that's about as good as it gets. You'll have a good day now and then when you can get beyond that but the environment is a huge factor. Good example - the other evening on my way home from work I talked to a guy about 2000 miles away but couldn't hear someone 10 miles away from me who was also talking with him.

Most radios will reduce your transmit power if SWR is high to avoid damage. If you find you can hear people clearly 2-3 miles away but you can't talk to them, that may be what's going on.
 
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