High swr with Tri mag mount

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MrPaul009
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High swr with Tri mag mount

Post by MrPaul009 »

Hi all my mate has just setup a radio for mobile but has a problem.he got a Tri mag mount and a thunderpole scarlet warrior bull whip.he also has a full 1/4 tank whip.problem is the bull whip will only cover the UK 40 block,when he tried it on the midblock the swr goes to nearly 2.0.he pull the top whip as far as he can and still the same.also the tank whip goes off the scale.tried the coax with multi meter and that's fine.not Shure what he can do?any ideas
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Mudslinger
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Re: High swr with Tri mag mount

Post by Mudslinger »

Have you checked the connection at the manet end of the coax?

The tank whip at least should give a very good SWR across many channels with no adjustment.
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MrPaul009
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Re: High swr with Tri mag mount

Post by MrPaul009 »

Hi Simon,I will message him that.many thanks
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Mudslinger
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Re: High swr with Tri mag mount

Post by Mudslinger »

Check there is continuity between the outer of the coax/PL259 and the magnet base and continuity betwen the PL259 centre and the antenna stud, but not between the two.

Some new magmounts are very poor in this respect, especially if they came from Maplins/Moonraker.
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The Collector
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Re: High swr with Tri mag mount

Post by The Collector »

Try a temporary ground/earth wire from the trimag's frame and the car body, say onto a scraped-down metal bolt on the door hinges for example. It might not make a difference, but if it does then something may not be quite right.
Last edited by The Collector on 24 Apr 2018, 11:07, edited 1 time in total.
MrPaul009
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Re: High swr with Tri mag mount

Post by MrPaul009 »

Hi there lads,yes he has tried the coax with a meter and that's fine to the base and where the antenna screws in.its a strange one especially with two antennas
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andrew013
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Re: High swr with Tri mag mount

Post by andrew013 »

whats the car try moving magmount around the roof say corner middle rear middle etc can make a differnce but scarlet warriors are normally pretty eay to swr whip all the way down and a few mm up job done , saying that a swr of 2 is f all really
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ch25
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Re: High swr with Tri mag mount

Post by ch25 »

MrPaul009 wrote: 23 Apr 2018, 13:35the bull whip will only cover the UK 40 block,when he tried it on the midblock the swr goes to nearly 2.0.
Seems fine. Below screenshot from antenna analyser. Single mag mount, centre of roof.
Image
MrPaul009 wrote: 23 Apr 2018, 13:35 the tank whip goes off the scale.tried the coax with multi meter and that's fine.not Shure what he can do?
Put magnet at the middle of the roof and open doors. SWR will go down. Tested.
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