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Swr problem on 102" whip

Dannell Boyd

New Member
Nov 15, 2021
23
22
3
69
Magnolia, MS
Hi,. I just trying to get started in CB, so I have to crawl before I walk. I have a mobile radio in my home hooked to a 102" steel whip and spring mounted to 20' pole and my swr as running 1.9 to 2.5 I tied to adjust but no luck. I noticed my pl259 wouldn't tighten up properly on the radio, cheap coax and connectors ? So I got some new coax gray 8x, that connected properly on each end, Damn the swr are even higher now.3 / 3.2 lol the way through. Are you supposed to shorten or raise to lower swr ?? Now the pole is right next to my mobile home, could that be the problem ???
 
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Riverman

Old Member
Nov 12, 2013
2,668
2,657
273
Take a look at this antenna. You need at least one wire radial (about 103”) for counterpoise. (Hard to see in the pic because the wire is black). Connect it to your antenna bracket. Angle it down slightly.
103” should work fine, but lengthen/shorten the wire to adjust SWR.
Connect the far end of wire to string or rope if needed.


C9166BA0-FDF1-459B-BE62-108B323857C9.jpeg
 

Dannell Boyd

New Member
Nov 15, 2021
23
22
3
69
Magnolia, MS
Thanks, like some kind ground ? I have the antenna mount, and pole grounded to ground rod. It's a mobile steel whip, will that make any difference ? I could see the wire in your picture. Thanks, Dannell
 

Recon

NY 881
Jul 28, 2019
770
976
103
Up-State NY
Hi,. I just trying to get started in CB, so I have to crawl before I walk. I have a mobile radio in my home hooked to a 102" steel whip and spring mounted to 20' pole and my swr as running 1.9 to 2.5 I tied to adjust but no luck. I noticed my pl259 wouldn't tighten up properly on the radio, cheap coax and connectors ? So I got some new coax gray 8x, that connected properly on each end, Damn the swr are even higher now.3 / 3.2 lol the way through. Are you supposed to shorten or raise to lower swr ?? Now the pole is right next to my mobile home, could that be the problem ???
How is the PL259 connected to the antenna? Can you provide photos of your installation?
 

Riverman

Old Member
Nov 12, 2013
2,668
2,657
273
Thanks, like some kind ground ? I have the antenna mount, and pole grounded to ground rod. It's a mobile steel whip, will that make any difference ? I could see the wire in your picture. Thanks, Dannell

It's different from an earth ground. The radial(s) provide the other part of the antenna that's missing. One radial will sometimes work fine. That's all I'm using. But 2 or more are better. Evenly spaced apart.

It's kinda like hooking it to your vehicle. The metal on the vehicle provides counterpoise.
On a pole, radials provide it.
 
Last edited:

Recon

NY 881
Jul 28, 2019
770
976
103
Up-State NY
Hi,. I just trying to get started in CB, so I have to crawl before I walk. I have a mobile radio in my home hooked to a 102" steel whip and spring mounted to 20' pole and my swr as running 1.9 to 2.5 I tied to adjust but no luck. I noticed my pl259 wouldn't tighten up properly on the radio, cheap coax and connectors ? So I got some new coax gray 8x, that connected properly on each end, Damn the swr are even higher now.3 / 3.2 lol the way through. Are you supposed to shorten or raise to lower swr ?? Now the pole is right next to my mobile home, could that be the problem ???
Is it possible the antenna connecter on the back of radio is defective? Do you have another radio to check the SWR?
 

Dannell Boyd

New Member
Nov 15, 2021
23
22
3
69
Magnolia, MS
Is the SO-239 isolated where it passes through the bracket? A photo is worth a thousand words!
Yes have two radios and checked both, had same problem. That pl259 connector on the coax doesn't pull in all the way and you can wiggle it slightly. I didn't want to tighten it too tight. Didn't have that problem with the new coax.
 

Dannell Boyd

New Member
Nov 15, 2021
23
22
3
69
Magnolia, MS
It's different from an earth ground. The radial(s) provide the other part of the antenna that's missing. One radial will sometimes work fine. That's all I'm using. But 2 or more are better. Evenly spaced apart.

It's kinda like hooking it to your vehicle. The metal on the vehicle provides counterpoise.
On a pole, radials provide it.
Ok I understand now.
 

Recon

NY 881
Jul 28, 2019
770
976
103
Up-State NY
Yes have two radios check both, seprobl

I have a L bracket with u-bolted to end of pole have so-239 on bracket with spring screwed on to it and antenna screwed on the spring.
Is the L-Bracket the standard / typical CB antenna (mirror) bracket with plastic spacers, SO-239 on the bottom and a 3/8-24 fitting on the top side, is a "home-brew" L-Bracket?
 

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