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 weird swr on full size g5rv 
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Post weird swr on full size g5rv
ok I put my full size g5rv back up but I added a 15ft alloy pole so it now has the pole plus the 10ft section from a big stick antenna witch has a 14inch bar with a pully to rope on the apex of the g5 the legs of the g5 are straight out and are about 8ft or more off the ground the swr is low on 80m and 40m ??? its high on the other bands it does work on all the bands with my mfj 969 I thought the tuner maybe was giving funny swr readings so I tried another swar meter it shows the same readings any ideas on this guys, ps no balun or rf choke is used


Mon Jul 29, 2013 6:33 pm
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 weird swr on full size g5rv 
Silent Key

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Post Re: weird swr on full size g5rv
Firstly you need a wideband 1:1 balun where the ladderline transitions to coax.

Does the ladderline run near a conducting pole?

Steve G3TXQ


Mon Jul 29, 2013 7:10 pm
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 weird swr on full size g5rv 
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Post Re: weird swr on full size g5rv
Hi Steve the ladder line slopes away from the pole at the apex its roughly 3 feet from the fiberglass bottom of the big stick as for the balun I haven't used one on this antenna and it was ok before I put it up higher whats the best 1.1 balun to use thanks


Mon Jul 29, 2013 8:15 pm
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 weird swr on full size g5rv 
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ok I have had to put the g5rv into an inverted v now the swr is not low on any band receive and transmit are fine its just weird they way its acting with the swr when horizontal


Mon Aug 12, 2013 12:14 pm
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 weird swr on full size g5rv 
Silent Key

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Post Re: weird swr on full size g5rv
Have you tuned it in the new configuration?

The G5RV has certain design parameters: the dipole should be 3/2λ long on 20m and the ladderline should be electrically 0.5λ long. Unless both those things are right you wont get the expected SWR figures. Some details on how to tune it here:
http://vk1od.net/antenna/G5RV/optimising.htm

Steve G3TXQ


Mon Aug 12, 2013 12:24 pm
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 weird swr on full size g5rv 
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Post Re: weird swr on full size g5rv
Hi Steve its not a home made g5rv its not too bad on the swr 3 is about the highest ill hopefully have a valve radio shortly so should be ok with that without having too use an atu hopefully thanks for the help Steve dave


Mon Aug 12, 2013 1:50 pm
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