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Swr problem on 102" whip

Recon

NY 881
Jul 28, 2019
789
998
103
Up-State NY
View attachment 56833
hello everyone, removed the spring, installed different so-239 and 2 radials and I now have 1.4 SWRs on 1/20/40. I never could hear so many truckers before on the interstate, 8 miles away. I asked for a radio check, and got a answer said they could hear me good. So thanks everyone for the help.
What is the difference of the first SO-239 and the new SO-239? Did you (piece by piece) troubleshoot to determine what caused the high SWR? It is always a good thing to share the results of your troubleshooting to forum members. Was the first SO-239 defective? Was the spring a contributing factor to the high SWR?
 
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Dannell Boyd

New Member
Nov 15, 2021
23
22
3
69
Magnolia, MS
What is the difference of the first SO-239 and the new SO-239? Did you (piece by piece) troubleshoot to determine what caused the high SWR? It is always a good thing to share the results of your troubleshooting to forum members. Was the first SO-239 defective? Was the spring a contributing factor to the high SWR?
I don't think anything was wrong with the first so-239 ( Wilson ), but I couldn't take it apart to see what was under that black cover. That's some hard material. Couldn't get it off without destroying it so I put a different type so-239 on it. Some one posted some different photos and it was one of those ( road pro rp-302MAX maxi stud. I think removing the 4" spring and putting those radials on did the trick. At first I thought if a whip worked on a mobile it should work on a pole but I wasn't considering the ground plane effect.
 

Crawdad

Down in the mud invasive species
Nov 11, 2016
873
1,816
153
I had issues with the Wilson bee-hive mount in a mobile set-up. My issues disappeared when I replaced it with a stainless heavy-duty.
In my experience the light or medium duty springs can cause continuity problems when they've been used for a while. And IMO the spring is not needed for length in your current setup, especially for the upper half of the band.
Glad you're up and running and were able to solve your problems. The radials did the trick.

73
 
Last edited:

Recon

NY 881
Jul 28, 2019
789
998
103
Up-State NY
I don't think anything was wrong with the first so-239 ( Wilson ), but I couldn't take it apart to see what was under that black cover. That's some hard material. Couldn't get it off without destroying it so I put a different type so-239 on it. Some one posted some different photos and it was one of those ( road pro rp-302MAX maxi stud. I think removing the 4" spring and putting those radials on did the trick. At first I thought if a whip worked on a mobile it should work on a pole but I wasn't considering the ground plane effect.
I bought my first 102" stainless whip, spring and ball mount in 1970. A local "seasoned" CBer offered to help me install the antenna on the left rear quarter panel on my '65 Nova. When I arrived at his home with all the parts, the first thing he did was separate the coil spring with a large screwdriver, and I just about blew a gasket! He told me he was looking for the braided wire inside the coil spring which connected the top area of the coil spring to the bottom area. No braided wire! He threw the spring into the trunk and told me to take it back to the store and buy a spring with the braised wire. What did I know? I thought he was joking, but he wasn't. Would the missing braided wire have made a difference? I'll never know. I was twenty-two years old, and he was pushing seventy, I did not challenge him, and I located a coil spring with the braided wire.
We installed the antenna and life was great!
 

Marconi

Usually if I can hear em' I can talk to em'.
Oct 23, 2005
7,100
2,106
343
Houston
Recon, IMO your buddy was correct.

Just as a note, the quality of your spring may continue making a good connection, but it is also an issue to check if your setup ever presents a problem.

I do not like the idea of using a spring, but if it is necessary then keep a good eye on it.
 
Last edited:

Recon

NY 881
Jul 28, 2019
789
998
103
Up-State NY
Recon, IMO your buddy was correct.

Just as a note, the quality of your spring may continue making a good connection, but it is also an issue to check if your setup ever presents a problem.

I do not like the idea of using a spring, but if it is necessary then keep a good eye on it.
Using a marine 316 Grade Stainless Steel spring is the best because it will not rust. 304 Grade Stainless Steel has carbon content and will rust eventually when exposed to the outside environment. The standard springs are chromed / nickel plated mild steel and look great, but after a few days of the spring flexing, the plating flakes off and the rust starts.
The lock washers for the antenna sections supplied with the Antron 99 and the
I MAX 2000 are nickel plated mild steel. I assisted a local guy with assembling and installing a new (original 24-ft) I MAX 2000 and it took me forever to convince him to change out the plated mild steel washers with 316 stainless lock washers. He bought the stainless-steel lock washers at the local hardware store and they were 304 not 316. I sent him to the local boat marina to buy the 316 Grade lock washers. Oh my God! I thought he was going to have a heart attack when he complained of the cost for "two" 316 stainless steel washers.
I helped another guy disassemble an Antron 99 which he assembled and installed about two years ago because the SWR was climbing. He could not understand why the top section was "wiggling" where the two sections were joined. Sure enough, the plating on the lock washer had flaked-off and the washer was nothing but a piece of rust and about ninety percent disintegrated. There was a small amount of contact between the bottom and top sections. He installed a 316-grade stainless lock washer and was "on the air"!
 

Dannell Boyd

New Member
Nov 15, 2021
23
22
3
69
Magnolia, MS
Using a marine 316 Grade Stainless Steel spring is the best because it will not rust. 304 Grade Stainless Steel has carbon content and will rust eventually when exposed to the outside environment. The standard springs are chromed / nickel plated mild steel and look great, but after a few days of the spring flexing, the plating flakes off and the rust starts.
The lock washers for the antenna sections supplied with the Antron 99 and the
I MAX 2000 are nickel plated mild steel. I assisted a local guy with assembling and installing a new (original 24-ft) I MAX 2000 and it took me forever to convince him to change out the plated mild steel washers with 316 stainless lock washers. He bought the stainless-steel lock washers at the local hardware store and they were 304 not 316. I sent him to the local boat marina to buy the 316 Grade lock washers. Oh my God! I thought he was going to have a heart attack when he complained of the cost for "two" 316 stainless steel washers.
I helped another guy disassemble an Antron 99 which he assembled and installed about two years ago because the SWR was climbing. He could not understand why the top section was "wiggling" where the two sections were joined. Sure enough, the plating on the lock washer had flaked-off and the washer was nothing but a piece of rust and about ninety percent disintegrated. There was a small amount of contact between the bottom and top sections. He installed a 316-grade stainless lock washer and was "on the air
 

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