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852
Advanced Member
Username: 852

Post Number: 545
Registered: 3-2006


Posted on Friday, August 27, 2010 - 9:34 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Wilson 2000 on a mirror mount installed on a T800 Kenworth Dump truck, what length coax should be run? And would any other lengths work and what would be the effects?
Thanks
Tommy~852~CEF 750

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Flying_cloud
Member
Username: Flying_cloud

Post Number: 96
Registered: 4-2009


Posted on Saturday, August 28, 2010 - 9:15 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

852 from what I have read and been told length of coax does not matter just use what is needed for the run. I have used 50' and 5' and still have had SWR readings of 1.1
Flying High and Flying Proud!!!!!!!!

CEF# 1028
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Tech237
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Username: Tech237

Post Number: 1364
Registered: 4-2004


Posted on Monday, August 30, 2010 - 7:15 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Flying Cloud -= Do YOU?? The meter may read 1:1 at the radio, but is it really that?? Try measuring right at the base of the antenna, and the odds are you'll see a different reading.

FACT: you cannot get an accurate reading at the radio unless you have an electrical half wavelength of cable between the radio and antenna - that includes the length of the meters pick up loop.

852 - having said that use at least 18ft of cable - why do you think most pre-made cables/bases come in that length??
Tech237
N7AUS

God only made some many perfect head, on the rest he put hair.
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852
Advanced Member
Username: 852

Post Number: 546
Registered: 3-2006


Posted on Monday, August 30, 2010 - 8:20 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Thats what i have always heard also Simon,I was just wondering what to do with all that extra coax, or would it be ok to run a shorter length..
Also when checking the SWR, should i check it at the radio, or the base of the antenna??
Tommy~852~CEF 750

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Tech237
Moderator
Username: Tech237

Post Number: 1365
Registered: 4-2004


Posted on Saturday, September 04, 2010 - 7:15 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

At the base of the antenna is the most accurate place to measure UNLESS you are using that electrical half wave length of coax.
Tech237
N7AUS

God only made some many perfect head, on the rest he put hair.
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Flying_cloud
Member
Username: Flying_cloud

Post Number: 97
Registered: 4-2009


Posted on Sunday, September 05, 2010 - 9:01 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Simon i have never had a problem with my swr i have checked at the antenna and at the radio. i am not a tech but could you let me know why length of coax should affect swr?? i am always willing to learn.
Flying High and Flying Proud!!!!!!!!

CEF# 1028
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Tech237
Moderator
Username: Tech237

Post Number: 1368
Registered: 4-2004


Posted on Thursday, September 30, 2010 - 7:25 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

FLying Cloud - so for the slow response to your question, in the process of moving of everything is a mess right now.

The short answer is to read the article in Subscriber Preview -Articles - Coax Cable Facts and Fantasies, which explains all about it.
Tech237
N7AUS

God only made some many perfect head, on the rest he put hair.

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