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Message |
    
Hotwire
Senior Member
Username: Hotwire
Post Number: 2491
Registered: 1-2005
| | Posted on Saturday, May 31, 2008 - 7:34 am: | 
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This has been bugging me. The antenna appears to be operating just fine with a 1.1 swr.
The other day I checked for seperation between the center conductor and the outer braid of the coax while connected to the antenna. Using a multimeter on the resistance scale it is showing between 00.3 and 00.5 or what I would call a closed circuit or no seperation of the center conductor and ground. Could this be normal for the Imax 2000?
Can any Imax 2000 owners check their antennas and see what you get?
HELP!!!
KEEP IT REAL!
Kenny
cef491(27.115lsb)
2sf491(27.555usb)
Indiana
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2ir473
Intermediate Member
Username: 2ir473
Post Number: 146
Registered: 7-2002
| | Posted on Saturday, May 31, 2008 - 8:30 am: |
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That is normal.
The Imax antenna is DC coupled, which shows a short between the center conductor and the shield, but it does not affect the RF in a negative way.
Your antenna is working as it should with the match of 1.1 on the swr meter.
It is disturbing to see that short though, isn't it?
Paul
2IR473
CEF-218/ham #107
CDX8412
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Moderator136
Moderator
Username: Moderator136
Post Number: 871
Registered: 4-2005
| | Posted on Saturday, May 31, 2008 - 1:45 pm: |
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Hotwire
I just came in from outside from putting up a new Imax 2000 with ground plane up on a temporary pole (21'long).The Imax is going up on a tower (56') at the bottom of the Imax 2000 in a week or so. At the 51' is going to be a maco 5 horzontal beam.
At any rate its kinda strange seen your post just now and putting up the Imax!!!
The Temporary pole is on a hinge so i can test swr and adjust if need to.All i have to do is pull a pin.
Yes i did check it and came up with the same readings as you did. (00.4) My swr reading is 1:2:1 i call that great swr . Not very often do i get 1:1:1
Also what 2ir473(Paul) posted is correct , there is going to show a short. And yes its DC Coupled.
This is my second Imax2000 and my first ground plane that i put on the Imax. I put it up without the groundplane did test (SWR-Noise-Dummyload and ect) Swr was high so lower it down again. ( I adjust for a happy medium for 11 and 10 meter) Ok then i put the groundplane on and put it back up at 21' and checked everything.
What i did notice was local am traffic on 11 meter jumped up 1 s unit. And a little less background static. Its good so far!!! I do know that a groundplane is more effective at 56' than 21' we shall see what happens when its on the tower.I will keep you all posted when its up on the tower.
Thanks Hotwire for the Info and question
73
Hal~Moderator136~KCØSVC
CEF#0136/CEF HAM#23 ~ CVC#0004
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Marconi
Advanced Member
Username: Marconi
Post Number: 765
Registered: 11-2001
| | Posted on Sunday, June 01, 2008 - 12:21 am: |
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Hey guys, you cannot accurately read RF resistance at the feedpoint of an antenna using an OHM's meter. |
Hotwire
Senior Member
Username: Hotwire
Post Number: 2492
Registered: 1-2005
| | Posted on Sunday, June 01, 2008 - 10:48 am: |
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Thanks for the reply guys.
Marconi, Interesting and I beleive what you say is true and now my wheels are turning up there in my head.
I actually have two Imax 2000 antennas up at my house.
The Imax antenna I use shows the short.
The Imax antenna my father uses shows no short! What the frigg?
So according to you I'm doing it all wrong anyway and most likely everything is fine.
Been so used to mobile antennas and how they are supposed to work. I need to get my nose in some more books on base antennas!
Thanks again my friends. Your always a big help.73
KEEP IT REAL!
Kenny
cef491(27.115lsb)
2sf491(27.555usb)
Indiana
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Hyperno_1979
Advanced Member
Username: Hyperno_1979
Post Number: 650
Registered: 12-2005
| | Posted on Friday, June 20, 2008 - 5:56 am: |
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Mine is doing exactly what i want it to.....landfill at the rubbish dump.
Greatest piece of junk i ever purchased and glad to see the back end of it.
CEFFFCEF
Bob
CEF703/CVC26
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Hotwire
Senior Member
Username: Hotwire
Post Number: 2518
Registered: 1-2005
| | Posted on Friday, June 20, 2008 - 11:47 am: |
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KEEP IT REAL!
Kenny
cef491(27.115lsb)
2sf491(27.555usb)
Indiana
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Marconi
Advanced Member
Username: Marconi
Post Number: 775
Registered: 11-2001
| | Posted on Saturday, June 28, 2008 - 10:43 pm: |
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Hey Hyperno, why do you say the Imax is junk enough to just throw away? |
Big_m
Junior Member
Username: Big_m
Post Number: 11
Registered: 9-2007
| | Posted on Saturday, June 28, 2008 - 11:12 pm: |
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Moderator136, Did you ever put your Imax up on your tower? If so do the GP kits really help out up at 56ft? I wonder how many S-units you went up and should I get a GP kit? |
Hotwire
Senior Member
Username: Hotwire
Post Number: 2533
Registered: 1-2005
| | Posted on Sunday, June 29, 2008 - 4:04 pm: |
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YEAH! Don't put ALL the blame on the antenna now!
KEEP IT REAL!
Kenny
cef491(27.115lsb)
2sf491(27.555usb)
Indiana
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Canal_digger
Junior Member
Username: Canal_digger
Post Number: 22
Registered: 1-2008
| | Posted on Wednesday, July 09, 2008 - 7:50 am: |
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If it's operating fine and you aren't getting alarms from radio or SWR, then it's probably OK. At first I was skeptical about the Imax2K, but after using one for a while I can say at this time it's a great Omni. Just wish I could put it up higher. But still, on a 30' pole, I just spoke "briefly" from here in W. NY state to Fairbanks (unit 555), Alaska on a Magnum S-9. Not bad... |
Revpo
Intermediate Member
Username: Revpo
Post Number: 406
Registered: 7-2006
| | Posted on Friday, September 26, 2008 - 3:49 pm: |
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I know the next purchase will be a IMAX 2 k, my Maco bent over in IKE about 45 degrees, it is still working but needs to be replaced within the next few weeks.
My friend just purchased a IMAX at the copper's and has a 1.2 on it at 65 feet but has no grnd plane kit on it. His signal has dropped to me about 20 miles to a 3 from a 5, but he hears a lot better than I can for ground wave and short skip. I believe he is skipping over me since I am lower than him and my antenna is on top of the roof on a tripod.
I plan on putting/purchasing the grnd plane kit with it, as I have read many places it helps for noise etc. Anyone have thoughts on the grnd plane attachment or just go with the basic antenna.
REVPO/CEF795
73
REVPO/DOCTOR/CEF 795
Wavin a hand from the cornfields of INDIANA
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