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Jim GM4DHJ ...[_3_]

On 20/04/2021 07:03, Jim GM4DHJ ... wrote:
On 19/04/2021 18:52, M0IAX via rec.radio.amateur.moderated Admin wrote:

M0IAX

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Inflatable 2m/70cm Antenna

Posted: 19 Apr 2021 03:21 AM PDT
https://m0iax.com/2021/04/19/inflata...-70cm-antenna/

Over the past weekend we went out to a couple of high points in Exmoor
national park so that I could try out my 2m/70cm Inflatable Antenna
that I bought from www.radiogeeks.co.uk .

Both places were just a few miles from home Home is not suitable for
VHF/UHF bands due to it being half way down a hill leading to Withpool
so we are in a valley. I can get to GB3EX (70cm repeater about 25
miles away to the south) using an antenna in the loft but thats about it.

The Antenna

The antenna is housed inside an inflatable sleeve so like the HF
version the antenna when deflated packs up quite small and I can fit
both inflatable antennas into a pouch attached to my LC-192 Backpack.

LC-192 backpack with pouch attached

Pouch containing VHF/UHF antenna and the HF Version

It is fitted with about 6m of low loss coax and a PL259 plug and
requires no ground or radials so you have just about everything you
need to use it out of the box. Its waterproof and has extended RX for
airband.

Inflatable antenna with 6m CoAx

Inflatable Antenna and Stroage Bag

Deployment

Remove from the supplied storage pouch, inflate by blowing into the
valve and thats it, it works best elevated like any VHF/HF antenna but
if you are already at the top of a hill or other high point you can
just prop it up aginst something, hang it from a tree or, like I did,
use the velcro straps to attach it to a pole.

Winsford Hill looking towards Withypool approx 400m ASL

radiogeeks 2m/70cm inflatable antenna on 10m pole

Thats what I like about this design. its simple, lightweight and self
supporting but small and portable when not in use.

Performance

OK so its a great design and great for portable use but does it work?

Portablle radio station IC705 LiFePo4 battery and SurfaceGo2

This weekend I was using a 10m pole, the car in the picture is used
only as a counterweight for the mast mount is provides no power to the
radio, that was done using either my 20Ah LIFEPO4 battery or on the
Saturday my PowerFilm Solar LightSaverMax (that I forgot to recharge
in the sun hence my reason for not using it on Sunday).

On Saturday with my radio set to 145.500 FM and 5W I had a QSO with
MW0UCL who was activating SOTA GW-SW007, turns out he had an IC705 as
well so we switched to DV and the radio measured the distance between
us as 74.6KM (46.4miles) audio quality was perfect both FM and DV and
59+ signal report.

Icom IC705

Sunday I didnt have too much time so I set up for about 1/2 hour of
operating and chose FT8 on 2m (144Mhz) as a the best mode to use so
that I could easily see where I was being heard on PSKReporter.info.
Setting up is a breeze, the mast and antenna were deployed in a couple
of minutes and I was on the air with 10w from the IC-705 connected
wirelessly to my SurfaceGo2.

As you can see from the map below, it works very well, with spots over
200miles away (I had similar results the day before and a couple of
weeks ago so wasnt just conditions on the day)

Once finished, tear down and packing everything back in the car took
just another couple of minutes.

Conclusion

This is a well made, simple to use, self contained and self supporting
antenna that works very well. Perfect for a SOTA or POTA activation or
carrying with you to greatly improve the performance of your hand
held. As I have said before I like this design, I will be keeping it
in the black pouch you see attached to my LC-1923 along with the HF
version so that I always have a quick deploy antenna solution, this
version will be my primary antenna for 2m/70cm.

73

Mark M0IAX

nice to see an old GM3 running that company.....
GM3HNN...Quality era ...amazed he is still alive and looking so young....