CB radio help. High SWR readings (1 Viewer)

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I installed the following in my 100 series
1) cobra 75 wx st

2) firering I just checked my order. I got the MU-r18 Amazon.com: Firestik Antenna FireStik MU8R18 18-Foot Single Antenna Coaxial Cable: Electronics
There's another one that's K-8r8 Amazon.com: FireStik K-8R18 18 foot Fire-Flex coax cable with Fire-Ring: Electronics
What is the difference between the 2?


3) antenna spring Amazon.com: Firestik SS-3H Heavy Duty Stainless Steel Antenna Spring: Automotive

4) labrak mount

I got a SWR meter and my readings are high. Ch 1 and 40.
When I flip the switch the needle drops from the end down to 3.

What am I doing wrong here? I ran power for the CB to the cigarette lighter. I grounded the ground wire on the unit to a screw by the shifter. The box for the CB is just sitting under the center console not bolted down.

Am I using the meter incorrectly? Did I miss something in the installation?

Thanks
 
Here's my setup with the fire ring

20170618_014558.jpg
 
You can try running power & ground directly to the cb itself, also bring a ground wire to the antenna mount to see if that helps (just throw up a temp wire) also how tall is the antenna. it should be atleast 1' taller than the tallest object on your roof, rtt etc.

what's your swr reading at channel 20?

I had similar issues, I went from 2.5 to 2.1 just by moving my antenna another 14" away from my windshield. Apparently this curve is very common. I want a lower swr and it's either the cable (fire ring here too), height of the antenna, mounting location, or grounding plane
 
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Not much ground plane under your antenna; you may need a 1/2-wave antenna to get reasonable SWR. A lot of CB antennas are 1/4-wave and they need a good ground plane to work well.
 
I have a 4 ft firestik so it's about 2 feet over the roof of the car.
What do you mean by bring a ground wire to the antenna?

I didn't check ch 20 since ch 1 and 40 I was getting 3 at those channels.



This is the antenna I have FIRESTIK II 4 FOOT 5/8 WAVE CB ANTENNA
 
You need to check channel 20 to make sure your getting a parabolic swr reading. if your getting the same swr reading across all the channels something else is wrong , i.e. pinched cable etc.

You can just run a temporary wire from the ground of the battery terminal to the mounting bracket bolt to see if that helps the swr reading. if it does you don't have a good/strong ground at the bracket & as such at the antenna itself

Also my radio says anything over 2 is not acceptable and since I only use the cb when I'm wheeling, I just spot tune it before I go out and adjust it so the low point it at the channel were using. it kinda sucks but it takes like 1.5 minutes
 
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This is the antenna I have FIRESTIK II 4 FOOT 5/8 WAVE CB ANTENNA

A 5/8-wave antenna also needs a ground plane to reflect off of to tune up well. You will get a little bit of a ground plane from your roof, since the antenna sticks up 2 feet above it, but probably not enough. Try a 1/2-wave antenna; they are much more forgiving of (lack of) ground plane.
 
I'm wondering if my Labrak antenna mount is giving me a bad ground. I tried to test continuity and nothing. I sanded down the 2 holes for the mounting bolts and tested from there and then there was continuity. Do I need to sand the whole bracket down?

my ch 20 is just barely lower if anything. It's almost all the same. I wonder if my SWR is bad? Is there anyway to check that?

Also, I was able to hear some chatter when I was on ch 20. nothing really on the other channels.

Might have to run to home depot or something tomorrow to pick up a wire and run it from the battery to the bracket and see if it's a ground issue.
 
You def have an issue. run a temp ground wire directly to the bracket. do not try to transmit with your cb, listening is ok.

High swr on all channels is a significant indicator that you have a ground issue or other installation issue
 
I sanded off some of the powder coat on the bracket by the firering and where it mounts to the car. I also removed the spring and my SWR reading went down to 2. By removing the tip of the antenna completely the reading went down a little bit more too. Is it possible that the antenna is just entirely too long?

I also noticed the that reading is different depending on if I hold the meter horizontally or vertically. Is this a faulty meter?
 
Are your readings the same on every channel or are your results parabolic? your antenna has the adjustable threaded tip, you need to adjust it so the reading on 1 & 40 are the same or similar and you need to put the tip back after you adjust it.
 
As stated above, your antenna mount needs to be grounded to the chassis. (Number 1 cause to HIGH SWR is lack of ground plane, but an ungrounded mount just adds to it.) I would leave the spring in, Firestiks are pretty rigid and the lack of spring can damage the "internal workings" of the antenna. I've smacked mine on a few parking structures, trees, and drive-thrus, when I had it on my '10 Ridgeline.
 
Here's my setup with the fire ring

View attachment 1480856
cb-antenna-mount-184380


As stated above, your antenna mount needs to be grounded to the chassis. (Number 1 cause to HIGH SWR is lack of ground plane, but an ungrounded mount just adds to it.) I would leave the spring in, Firestiks are pretty rigid and the lack of spring can damage the "internal workings" of the antenna. I've smacked mine on a few parking structures, trees, and drive-thrus, when I had it on my '10 Ridgeline.

This may go without saying but look at the diagram and make sue you follow it. Also remember you may need to grind off some powder coat for a good ground connection.

View attachment 1635812

As stated above, I would put the spring back in, but right on top of the mount. This would put a larger base against the mount bracket.
 
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