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Hound_dog
New member
Username: Hound_dog

Post Number: 1
Registered: 10-2007
Posted on Thursday, October 04, 2007 - 7:18 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

I put up a shooting star antenna last weekend and followed the instructions of setting SWR. On the ground I was able to get 1.4 (1-40)vertical and 1.3 horz(1-40). When I put the tower up The vertical swr never went down like its supposed too. I could have LIVED with these readings but I found that when I switched my radio to med or high power, the swr's shoot above 2! Can someone tell me how to properly set this antenna up on the ground to have good SWR.
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Marconi
Advanced Member
Username: Marconi

Post Number: 755
Registered: 11-2001


Posted on Thursday, October 04, 2007 - 10:18 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

The SWR should not change when changing power levels. Are you re-calibrating you meter as you switch power levels?
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Hound_dog
New member
Username: Hound_dog

Post Number: 2
Registered: 10-2007
Posted on Thursday, October 04, 2007 - 5:29 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Yes, I recalibrate when checking swr with different power levels. Actually I've even checked the SWR's without recalibrating as well, and still had the same SWR readings. I will drop the antenna this weekend and try messing with the gammas again. Someone else told me to try running a ground wire from the antenna boom to a good ground.
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Marconi
Advanced Member
Username: Marconi

Post Number: 756
Registered: 11-2001


Posted on Friday, October 05, 2007 - 6:29 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Well that makes a lot of sense. I would question your meter or how you have this dual polarity beam hooked up, before I go messing with the tune.

This antenna does not need a ground to work.
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Train_man
New member
Username: Train_man

Post Number: 3
Registered: 10-2007


Posted on Friday, October 05, 2007 - 11:45 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

I will have to agree with Marconi. I would check the coax, connectors, jumpers etc before messing with the gammas. If the swrs were as stated on the ground, then something changed as it was installed on the tower. Did you use the same coax for tuning the antenna as you did for the final install? Also, what antenna switch are you using? There are some cheap ant switches out there that are junk.
Just a few things to check.

Move along. Nothing to see here.........
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Sonny
Intermediate Member
Username: Sonny

Post Number: 170
Registered: 5-2004
Posted on Friday, October 05, 2007 - 10:42 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

dog, I assume when you have it at ground level you have the beam pointing up at the sky is the best way while not touching the ground so there is absoultly nothing in front.
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Moderator136
Moderator
Username: Moderator136

Post Number: 492
Registered: 4-2005
Posted on Sunday, October 07, 2007 - 11:25 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

It sounds like a bad coax connetions some where inline.Or jumpers are bad.If you drop the beam check coax with a ohm meter. Wish you good luck and let us know what you find?
Hal ~ Moderator136 ~ KCØSVC
CEF#136/CEF HAM#23 ~ CVC#004
Moderator136@copperelectronics.com
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Captian_radio
Intermediate Member
Username: Captian_radio

Post Number: 250
Registered: 9-2004
Posted on Tuesday, October 09, 2007 - 3:26 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

This might sound crazy but the old timers used to stand the beam on end with the reflector on the ground.I know this sounds odd but if have also done it this way to tune the antenna to resonance and it worked fine for me.This has something to do with the ground reflection and its effect on proper tuning.
Lots of things can affect the final tuning -radiation resistance of the ground ,near by metallic objects such as wires , even the tower and mast pipe it self can be a factor.
CEF451/VE1CZ
Robert L. Spicer The days of radio are just beginning!

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