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This year we have decided to improve upon our satellite operations from the Isle of Lewis, the original plan was to use a simple setup of a Yaesu FT-817 and a Arrow satellite yagi – although this setup works amazingly well as we proved last year on the Isle of Mull it does have the downside of making you stand outside in all weathers, and this year we are further north!

photo of the Wimo X-Quads setup for testing in G1SAAs garden.

Wimo X-Quads setup for testing in G1SAAs garden

So this year we plan to trial Bob G1SAA’s satellite equipment from the island, the new station comprises Wimo X-Quads for 2m and 70cms with SSB electronic Preamps (SP-2000/SP-7000) and a Yaesu G-5400B Az/EL rotator supported on a speaker stand.

Inside the shack we’ll be using a Foxdelta ST-2 tracker (LVB Clone) connected to the rotator & ICOM IC-910 transceiver, this will all be controlled using a laptop running SatPC32.

We’ve had a number of people asking what satellites we will be using, these will be the ones we target;

Satellite Uplink (MHz) Downlink (MHz) Mode(s ) Website
AO-7 (Mode B) 432.125 – 432.175 145.975 – 145.925 SSB / CW http://goo.gl/s2p4za
VO-52 435.225 – 435.275 145.925 – 145.875 SSB / CW http://goo.gl/wk7R1v
FO-29 145.900 – 146.000 435.900 – 435.800 SSB / CW http://goo.gl/IjuHUq
SO-50 145.850 436.800 FM http://goo.gl/ibjXyx
AO-73 435.150 – 435.130 145.970 – 145.950 SSB / CW http://goo.gl/wqq7Rt

All bar one of these are SSB/CW transponder satellites, see the AMSAT guide on linear transponder operating if you are unfamiliar with it, although our main focus will be SSB QSOs we can probably do CW as well however we’d recommend that you send in a sked, or ask on hf, so that we can make sure a suitable operator is available.

Of course if any other satellites with transponders become available we’ll of course endeavour to use those as well. And I’m sure you’ll still hear us using our Yaesu FT-817s and a Arrow satellite yagis if the weather is nice.

Following on from the previous satellite antenna posts here is an update on what happened after the antennas were received. At first I wanted to build cross yagis for 2m and 70cm as the HyGain ones I had previously seemed rather poor in terms of performance. I hunted the web for some designs and couldn’t find anything – I then thought I’d look for simple non crossed yagi designs which had boom lengths around 2m then modifying it to be crossed but again it was hard to find anything decent. As the antennas will be used on the Arran DX’pedition I also had reservations about using a design not specifically based around a cross yagi or built for the satellite portion of the band.

I then looked at the UK retailers to purchase satellite antennas and again nothing which met my requirements!

Thankfully I bumped into previous dx’peditioner Geoff DDX one morning on the local Cambridge CRG repeater GB3PY who told me Brian G6HFS had recently purchased some and I should speak with him, well a phonecall to Brian and I was on the Wimo website, Wimo are predominantly an antenna and antenna systems company in Germany http://www.wimo.com/.

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Having a look on their site I found exactly what I needed! Pretty much the same as what Brian ordered! In the end I ordered a 7 element cross yagi for 2m (10dBd) and a 10 element cross yagi for 70cm (11.5dBd) plus a phasing harness for each to allow circular polarisation, fitted to allow right hand circular polarisation.

Well the antennas arrived from Germany 2 working days after ordering and off I went to build them, 2m first then 70cm. As I started on the 2m one it soon became apparent that the holes drilled for the directors were done incorrectly. The boom comes in 2 parts, the front and back (joined at the mounting point in the middle) and even my housemate who came out to help noticed the holed were miss aligned.

2m_Squint_Element

I ended up re-drilling the mounting holes to get it back to being level.  I emailed Wimo on this and with no quarrel they are sending me a new boom section over to replace this one. Wimo are known for their quality so I’ve no idea what happened here – but their customer service is spot on!

Due to the 6m UKAC on Tuesday and the Arran planning meeting on Wednesday I only got round to mounting the antennas last night. They are not very high, about 4 feet up, and they sit in part of the old pond next to the shack well below the bushes, shack, SCAM antennas etc, this is them pointing about 330 degrees.

Sat_Antennas (Large)

Anyway even mounted where they are I can hear the PI7CIS beacon @284Km in Holland, but very weak, if you look at the photo you can see a fence about 1m higher than the antennas which is the direction to PI7CIS! Thankfully there was a VO-52 pass not more than 5 minutes after I got everything connected up and our new Arran DX’pedition member Pete 2E0SQL was about and ready to be active on the pass. So I fired up the HRD satellite tracking software to steer the antennas and low and behold the beacon appeared at 2 degrees elevation! At 5~10 degrees I tuned my IC-910 to where Pete was on the transponder and he was S7! With no trouble at all we worked and he was first in the log on this new setup…

The elements are mounted to the boom direct (and electrically) with a single 50mm M3 cross head screw and nylon insert nut. Fine for permanent installs but fiddly and such like for going /P, i.e. Arran. So this week I got off eBay I got some 50mm M3 hex head screws and M3 wing nuts which will allow disassembly and transport much easier, something we again struggled with with the old HyGain antennas.