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I'm not sure about that Marconi. The coax was directly from the factory cut this length for use for in or outdoor cell sites for the GPS antennas. The length of 60ft was never actually used. Always what reached point A to B was used and the rest either scrapped or used for another job.
Does this make sense???
I understand what you're saying but I don't think that the coax I have setup in totality is actually a 1/2 wave length of the given freq of 27.405. I guess I would have to know the true length of the coax line that is just after the main 60ft run. Like I said, all the coax I have attained are 60ft or shorter runs of coax. I didn't pay for any of it. And I have never had this issue before. I've always used what worked from point a to b.
Do you beleive the 60ft coax is a 1/2 wavelength of 27.405??
I don't think it is. But hey I could be totally wrong. A 1/4 wave length jumper for 27.405 using lmr400 is approx. 7.62ft.
I used the formula of L= 246 div. by 27.405, then mult. by VF which is 85% for said coax which is Andrew CNT400 (LMR400 equivalent). So with this said, if we multiply this by 2 this would be a 1/2 wavelength for 27.405mhz, which would be 15.25ft. So with this I can multiply by 2 more and have a full wave length for said freq. which would be 30'6". This would place my coax jumper of 60ft out of line as well as the total I get is 61ft. Would 1ft of coax make a difference??
And if this were the case then I really didn't tune my antenna correctly if a 1/2 wavelength coax jumper is needed for tuning correctly. And I would like to know why? Thanks for the replies and I know I have opened up a can of worms here, so let the flaming begin LOL!!

<blockquote data-quote="222DBFL" data-source="post: 537673" data-attributes="member: 36544">I&#039;m not sure about that Marconi.&nbsp; The coax was directly from the factory cut this length for use for in or outdoor cell sites for the GPS antennas.&nbsp; The length of 60ft was never actually used.&nbsp; Always what reached point A to B was used and the rest either scrapped or used for another job. Does this make sense???I understand what you&#039;re saying but I don&#039;t think that the coax I have setup in totality is actually a 1/2 wave length of the given freq of 27.405.&nbsp; I guess I would have to know the true length of the coax line that is just after the main 60ft run.&nbsp; Like I said, all the coax I have attained are 60ft or shorter runs of coax.&nbsp; I didn&#039;t pay for any of it.&nbsp; And I have never had this issue before.&nbsp; I&#039;ve always used what worked from point a to b. Do you beleive the 60ft coax is a 1/2 wavelength of 27.405?? I don&#039;t think it is.&nbsp; But hey I could be totally wrong. A 1/4 wave length jumper for 27.405 using lmr400 is approx.&nbsp; 7.62ft. I used the formula of L= 246 div. by 27.405, then mult. by VF which is 85% for said coax which is Andrew CNT400 (LMR400 equivalent).&nbsp; So with this said, if we multiply this by 2 this would be a 1/2 wavelength for 27.405mhz, which would be 15.25ft.&nbsp; So with this I can multiply by 2 more and have a full wave length for said freq. which would be 30&#039;6&quot;.&nbsp; This would place my coax jumper of 60ft out of line as well as the total I get is 61ft.&nbsp; Would 1ft of coax make a difference??&nbsp; And if this were the case then I really didn&#039;t tune my antenna correctly if a 1/2 wavelength coax jumper is needed for tuning correctly.&nbsp; And I would like to know why?&nbsp; Thanks for the replies and I know I have opened up a can of worms here, so let the flaming begin LOL!!</blockquote>

[QUOTE="222DBFL, post: 537673, member: 36544"] I'm not sure about that Marconi. The coax was directly from the factory cut this length for use for in or outdoor cell sites for the GPS antennas. The length of 60ft was never actually used. Always what reached point A to B was used and the rest either scrapped or used for another job. Does this make sense??? I understand what you're saying but I don't think that the coax I have setup in totality is actually a 1/2 wave length of the given freq of 27.405. I guess I would have to know the true length of the coax line that is just after the main 60ft run. Like I said, all the coax I have attained are 60ft or shorter runs of coax. I didn't pay for any of it. And I have never had this issue before. I've always used what worked from point a to b. Do you beleive the 60ft coax is a 1/2 wavelength of 27.405?? I don't think it is. But hey I could be totally wrong. A 1/4 wave length jumper for 27.405 using lmr400 is approx. 7.62ft. I used the formula of L= 246 div. by 27.405, then mult. by VF which is 85% for said coax which is Andrew CNT400 (LMR400 equivalent). So with this said, if we multiply this by 2 this would be a 1/2 wavelength for 27.405mhz, which would be 15.25ft. So with this I can multiply by 2 more and have a full wave length for said freq. which would be 30'6". This would place my coax jumper of 60ft out of line as well as the total I get is 61ft. Would 1ft of coax make a difference?? And if this were the case then I really didn't tune my antenna correctly if a 1/2 wavelength coax jumper is needed for tuning correctly. And I would like to know why? Thanks for the replies and I know I have opened up a can of worms here, so let the flaming begin LOL!! [/QUOTE]

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