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a99

4

4600turbo

Active Member
Aug 27, 2006
151
0
26
Hi, I got a clone version of the a99 Solarcon antenna and I broke one of the ground planes when I was installing it. So, I replaced the broken ground plane with the top section of the antenna since it was the same size. I replaced the top of the antenna with a 102" steel whip.

Now to my question. I've checked my SWR and found it was flat at 26.195. It shows 1.9 to 2.0 on the regular 40 channels. Since this is just for CB. I was wondering if the rings would adjust the SWR back up the 27.185.

The reason I'm asking and not doing is because I really difficult to get to the antenna. So if i can get reasonable advice and if it is possible. I will take the time to adjust the SWR down.

I know I have to lengthen the antenna. So the rings will go to the bottem of the antenna. Rignt now there set at factory spec's.

Do you guy's think just by adjusting the rings down will it get my SWR down flat at 27.185?
 
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Yeah, you guys are correct. I need to shorten the antenna, but do you think there is enough adjustment on the antenna to do this? I guess only really one way to find out. :)

Part of my problem was a faulty meter. Now it shows flat on channel ONE and 1.5 on channel 40 using the meter on the radio. I guess this will be ok for now.

I know meters on radios aren't that accuarte either, but it'll have to do until I get a good meter.

I found a problem with the meter when I was checking connections. It was showing SWR Alert on the radio. Now it doesn't.
 
take the antenna down, and cut that 102" whip down to 72". (6 feet)

then put the antenna on a 10 foot pole, or whatever you can rig to hold it upright and away from anything that might interfere with the antenna's tuning.

tune the antenna for lowest SWR on 1 and 40 using the rings.

then put the antenna way the hell back up there. LOL

i am a big fan of putting a little PENETROX on the threaded connections of the antenna.

later,
LC
 
loosecannon said:
take the antenna down, and cut that 102" whip down to 72". (6 feet)

then put the antenna on a 10 foot pole, or whatever you can rig to hold it upright and away from anything that might interfere with the antenna's tuning.

tune the antenna for lowest SWR on 1 and 40 using the rings.

then put the antenna way the hell back up there. LOL

i am a big fan of putting a little PENETROX on the threaded connections of the antenna.

later,
LC
Click to expand...


That would have been a good way to check it. I should have thought of it, but I was thinking that the setup I have was going to be easy to put up and down. Boy, was I wrong LOL.


Never thought of cutting the 102", because I thought the a99 was dipole with a 1/4 wave up on top. I know that the 102" is not quite a 1/4 wave and I thought I would have to re-adjust the rings to correct the SWR, but I didn't know which way to go with the rings, Up or down.

I was thinking since the antenna was actually physically longer than what was on top in the first place I had to go down on the rings, but since it's electrically shorter I guess I have to go up. I'm just not sure that the antenna rings can go up enough to compensate for the difference is what I'm asking.
 
Is there enough adjustment in those 'rings' to handle your antenna? That's one of those "maybe" questions, you won't really know till you try it. Pleasant thought, huh? They typically can manage quite a frequency adjustment range. They are not 'magic', though, so unless you really get lucky, count on a few "up/down"s before you're through/satisfied.
Good luck.
- 'Doc
 
What good does the Pentrox do on the threads, water does not enter thru the threads unless you are in a terrible flood. Use a product called Stuf from Cross Devices. It goes inside the PL239 and sheads water like off of a ducks back. No water will get into the coax with Stuf in there. Also make sure your weep hole in the bottom of the antenna is clear, at least it is that way in the Solarcon. Stuff is available for AES @ www.aeaham.com and is cheap.

I do not think you will be able to adjust the rings enough to get even close if you were right with the first scenario, but since you say there is a second scenarion, I'm not sure.

Good luck.
 
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those "rings" are used to effect an impedance match between the antenna and the feedline. no matter where you adjust them the resonant frequency of the antenna is determined by the overall length of the radiator.

the temporary solution here would have been to not worry about the broken radial element and find a replacement as time permitted. then the difficulty getting to the antenna would have never come into play.

as it is you're looking at getting to it again, one way or the other.
 
i am guessing, but i think you will not be able to use the rings to get the antenna SWR down.

you need to cut the top radiator down to 72" to bring the antenna back into resonance.


as for the penetrox, its not so much about water sealing, although that is an added benefit.

its about preventing oxidization and corrosion, and being able to get the antenna elements apart years and years after you put it up.

to each his own, but i like to use it.
LC
 
freecell said:
those "rings" are used to effect an impedance match between the antenna and the feedline. no matter where you adjust them the resonant frequency of the antenna is determined by the overall length of the radiator.

the temporary solution here would have been to not worry about the broken radial element and find a replacement as time permitted. then the difficulty getting to the antenna would have never come into play.

as it is you're looking at getting to it again, one way or the other.
Click to expand...


Is that electrical length or physical length? As, you know the 102" is not quite 1/4 wave and still the antenna is showing that it's to long on my SWR meter.

I was thinking that I was going to have to lengthen the antenna since the electrical length of the 102" antenna is shorter than 1/4 wave.
 
W5LZ said:
Is there enough adjustment in those 'rings' to handle your antenna? That's one of those "maybe" questions, you won't really know till you try it. Pleasant thought, huh? They typically can manage quite a frequency adjustment range. They are not 'magic', though, so unless you really get lucky, count on a few "up/down"s before you're through/satisfied.
Good luck.
- 'Doc
Click to expand...


Thanks, I can... live with the SWR as it is actually,for now, but of course would like to get it perfect. :)
 
4600,

it is the advertising claim that has confused you.

in the ads, the antenna is referred to as a "half over a quarter wave, mutual transductance tuned antenna".

the half wave antenna is on top of the quarter wave antenna.

now, i may be wrong here, and im sure someone will correct me if i am, but i thought i remembered reading that the antron 99 itself was the halfwave antenna (18ft.) and that the first 8.5-9 feet of coax was the quarter wave portion.

either way, you have to take your antenna down, so start studying the weather reports for a windless day or two!

good luck,
LC
 
loosecannon said:
i am guessing, but i think you will not be able to use the rings to get the antenna SWR down.

you need to cut the top radiator down to 72" to bring the antenna back into resonance.


as for the penetrox, its not so much about water sealing, although that is an added benefit.

its about preventing oxidization and corrosion, and being able to get the antenna elements apart years and years after you put it up.

to each his own, but i like to use it.
LC
Click to expand...

Sorry loosecanno, my bad. I just realized that the pentrox is not the sealer like gasket maker stuff I was thinking about. You are correct on the Pentrox use.
 

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