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RaDAR on 2Metres

Thomas Robinson
 

Hi I recently watched a Utube video by "Radio Prepper" regarding use of 2M SSB.
https://youtu.be/LaRsBtT52kc

This got me thinking about 2M SSB/CW for RaDAR use.  The key point of the video was the ease of deployment of the antenna he was using which is a design of M0UKD
https://m0ukd.com/homebrew/antennas/144mhz-2m-portable-yagi-vhf-beam-antenna/

The novel construction of this antenna makes it ideal for /P RaDAR use.  Assembly time for the antenna is claimed to be about 30 seconds.  I considered such an antenna mated with my RaDAR trolley would make an good combination.  I have therefore made one using bits and pieces I had available.  I had some 4mm solid Aluminium rod suitable as replacement for the 6mm tubing made in the design.  The resulting antenna has an SWR of 1.4:1 over 144.000 to 146.000.  I suppose I could start trimming elements to try improve the SWR but I think I will leave the antenna as is.  the antenna I have built seems quite robust enough for occasional /P outings.  Certainly it is very fast to assemble and deploy on the trolley.  Have made the mast adaptor suitable for fastening to the 10M Clark, extendable mast at the home QTH, should improve access to a couple of local CW practice nets. It can also be deployed from a 7M Aluminium mast fastened to the tow hitch of the camper van.

So, this should prove to be quite a useful addition to the antenna stable.  Just got to vanish it now.

Some photos below:-

N5VMO Pat
 

Very nice set up you built Tom =)   I really like the "cloths Pin" element attachment =)   Really makes it portable =)

Listening to the the SAT pass on AO-92 ( GREAT FOOTPRINT ) Saturday on the HT with Greg's group got me to thinking =)   I added the SAT frequencies to my mobile 2 m rig in the truck so if in travel maybe I can operated =)     I just missed the schedule by 15 minutes because traffic heading to the State Park mountain =(    I could hear the SAT for over fifteen minutes on that pass while being fifteen minutes late ( almost a total time of 45 min. for that pass alone once in place =)   I was even on the wrong side of the mountain driving up to the park and had perfect copy of the SAT 8-)   I could not use the HT while driving up a winding narrow road up the hill; but could listen =)   The mobile has Bluetooth headset and now has SAT frequencies in its memories 8-)




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73's Pat  N5VMO


Thomas Robinson
 
Edited

Thanks for the comment Pat.  Yes, M0UKD's clothes pin element fastening idea works well.  Its surprising how tight they grip the elements.  If 6mm tubing is used they would be gripped even more securely.  I am quite lucky to live in a coastal area.  Even though most of the area is at (and sometimes below) sea level, there are some highish cliffs that give a good take off over the North Sea to Holland, Belgium Germany and even Scandinavia on a  day with good VHF conditions.  Local contest groups tend to gather at one point in particular,  Walton- on-the-Naze at weekends.  Being retired from work I can give it a go on week days ;-)  At my home QTH i can hear Dutch and Belgian repeaters with a very small collinear when a lift is on.

N5VMO Pat
 

I always use to love to use the 2m and 70cm SSB and for SATs at home with my stacked pair of "Big Wheel" antennas and 300 plus watts of power =)    Easy everyday 400 mile contact and 900 mile contact into lower part of Canada =)   I still have the amps but the antennas got destroyed in the move to the apartment ... need to make more as they cost almost $150 each to buy now days and a few hundred for the power divider ( I made my own power dividers =)


On Wed, Apr 10, 2019 at 10:30 AM Thomas Robinson via Groups.Io <g0sbw=btinternet.com@groups.io> wrote:
Thanks for the comment Pat.  Yes, M0UKD's clothes pin element fastening idea works well.  Its surprising how tight they grip the elements.  If 6mm tubing is used they would be gripped even more securely.  I am quite lucky to live in a coastal area.  Even though most of the area is at (and sometimes below) sea level, there are some highish cliffs that give a good take off over the North Sea to Holland, Belgium Germany and even Scandinavia on a  day with good VHF conditions.  Local contest groups tend to gather at one point in particular,  Walton- on-the-Naze at weekends.  Being retired from work I can give it a go on week days ;-)  At my home QTH i can hear Dutch and Belgian repeaters with a very small collinear 
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73's Pat  N5VMO