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Allagator
Advanced Member
Username: Allagator

Post Number: 585
Registered: 9-2002


Posted on Thursday, April 28, 2005 - 5:02 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

when i had my A99 5 foot off the ground and stuck between the steps of my tower and i had a 1.2 on swr now its 48 foot in the air and now its at a 3 ?????
any ideas whats happened ??
buy the way sold the Imax cause it was hitting the tree limbs !


Thanks Allagator
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Crackerjack
Intermediate Member
Username: Crackerjack

Post Number: 380
Registered: 7-2004
Posted on Thursday, April 28, 2005 - 7:34 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Do you have the Groundplane kit? If not, that should cure the problem. I think.

I had a whip that was normally NO SWR, and placed it on a 30 foot pole. One side of the "EFFECTIVE" Vertical Dipole was 8 feet and the other was 30 feet. I replaced the mount with a groundplane kit and had a SWR that was dificult to measure.

That said, I am not familiar with the A99 GP KIT -but the theory of the whip/mast is the same.
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Bigbob
Senior Member
Username: Bigbob

Post Number: 1841
Registered: 12-2001
Posted on Thursday, April 28, 2005 - 7:55 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Sounds like a bad solder connection inside the antenna,Lon can direct you to the info here,I can't remember the exact location.Bigbob
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Kd4amg
Intermediate Member
Username: Kd4amg

Post Number: 172
Registered: 6-2003
Posted on Thursday, April 28, 2005 - 11:05 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

double check your coax

check rings to be sure they are in MIDDLE & tight ( not loose )

check to be sure all 3 sections are TIGHTLY screwed into each other ( but not too tight )

simple things you may not have checked...I have missed the OBVIOUS so many times it aint funny.

GOOD LUCK
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Road_warrior
Advanced Member
Username: Road_warrior

Post Number: 520
Registered: 7-2004
Posted on Thursday, April 28, 2005 - 11:28 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Since the Swrs were good when mounted 5
ft off ground, it should of been good
at 40 ft, in less something happened
to the coax or connector or the antenna
took a hard bump or its reflecting off
something...
I have also seen a A-99 that was mounted
beside a pine tree and SWRs went crazy.
Moved antenna away and SWR came down to
normal.

JIM/ PA/ CEF 375
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Yankee
Intermediate Member
Username: Yankee

Post Number: 488
Registered: 7-2003
Posted on Friday, April 29, 2005 - 2:09 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

I agree with checking the coax and the tuning rings. Also someplace on some website I remember that a vertical ground plane type of antenna reverses and makes a second image of the actual antenna, directly below the antenna. Therefore I tend to believe that coax length and height may have something to do with your SWR. Remembering that coax length and antenna height are measured in multipals of 9 feet, measureing from the ground to the tip of the antenna. Also making sure you have a good ground field. Just my thoughts after 42 years on the air and keeping a good SWR. Hope this is of some help.
Carl CEF-357
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Bigbob
Senior Member
Username: Bigbob

Post Number: 1847
Registered: 12-2001
Posted on Friday, April 29, 2005 - 6:29 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Some of the newer a99s had poor construction internally in product reviews there's a cut away photo showing this,and because of ground reflections 5 ft. may have masked this problem,or it may be something as simple as a broken solder connection at one of the coax connectors.My brother in law left his coax dangle at just 12 feet and it ripped out the bottom connector and all the guts,what a disgusting mess that was,there's alot of simple things to check and it's probably one of those,but a couple of years ago this guy had intermittant swr problems and it led to a bad solder joint inside on the tapped inductor,so he threw it away and bought a new one.Bigbob
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Road_warrior
Advanced Member
Username: Road_warrior

Post Number: 524
Registered: 7-2004
Posted on Friday, April 29, 2005 - 8:57 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

I've had 3 A-99s,but, the older models.
I mounted each one to my mailbox pole
to make sure they worked before putting
higher. About 1:3-1:4 while close to
ground. After installing in the air,
SWRS fell to 1:1-1:2.
One of them accidentally got bumped hard
and suffered what BigBob is talking about.
As the bad solder joint made it impossible
to get a good match. Actually, if a bad
solder joint exists it can go bad at anytime
without the antenna being bumped hard.
But, i would check all the easy stuff first
like is mentioned above in other posts.

JIM/ PA/ CEF 375
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Road_warrior
Advanced Member
Username: Road_warrior

Post Number: 525
Registered: 7-2004
Posted on Friday, April 29, 2005 - 9:29 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

I read some of those reviews you were talking
about Bigbob. I see what you mean.
I never owned a new one, but, never had
to much trouble wih the older ones.
My friend has a newer one, so, far its
working good. Been up for about 8 months.

JIM/ PA/ CEF 375
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Timebomb
Junior Member
Username: Timebomb

Post Number: 41
Registered: 2-2005
Posted on Friday, April 29, 2005 - 3:04 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

I bought my A-99 from Copper ten years ago. My match is 1:2 to 1:5 across the band, with it 40 ft. in pine tree. My rings are a tad off. No biggie.
Sounds like a coax problem to me. You didn't move the rings did ya? Is it still grounded OK? Hopefully it's not internal. Good luck.
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Allagator
Advanced Member
Username: Allagator

Post Number: 586
Registered: 9-2002


Posted on Friday, April 29, 2005 - 4:51 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

well i found the problem !!!! THANKS GUYS !!!!

dummy me forgot to tighten the coax and it was loose as a goose just hanging on the switch box !!!! LOL talking about dumb things to do !!! LOL that would almost rate number 1 in my book !!!
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Road_warrior
Advanced Member
Username: Road_warrior

Post Number: 527
Registered: 7-2004
Posted on Friday, April 29, 2005 - 10:47 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

At least its fixed, thats all that counts.
LOL..

JIM/ PA/ CEF 375
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Bigbob
Senior Member
Username: Bigbob

Post Number: 1848
Registered: 12-2001
Posted on Saturday, April 30, 2005 - 10:18 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

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Dx431
Senior Member
Username: Dx431

Post Number: 1027
Registered: 2-2002


Posted on Saturday, April 30, 2005 - 11:12 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)



Don't feel bad Jason, we've all been there done that.
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Dogfacedsoldier
Member
Username: Dogfacedsoldier

Post Number: 55
Registered: 10-2004


Posted on Sunday, May 01, 2005 - 12:24 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

i encountered the same prob turns out the higher up i went higher swr just had to re-tune it.

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