2024 Rally and Open Day – Sunday 27th October 2024

This year’s Galashiels Rally and Open Day will take place on Sunday 27th October 2024.

This is the last weekend of October so the morning of the clocks changing back an hour.

Venue as usual is the Volunteer Hall, St John Street, Galashiels TD1 3JX.

Traders booked so far (as of 22nd May 2024):
GQRP Club
Alan Clegg (valves etc)
Mirfield Electronics (Martin Stokes)
Canny Components
Mick Hunter (Batteries etc)
Tony Kruszelnicki (TK Electronics)
Perth Repeater Group
Peter Bates GM4BYF
Ken Elliott GM4NTX
Dave Bagshaw


More to follow.

Bring & Buy Stall
Catering with hot and cold refreshments.

New email for traders queries: rallytraders @ galaradioclub.co.uk
(The address rallytables was mistakenly given out but will also redirect automatically to rallytraders.)
General enquiries about the rally (not traders) to rallyqueries @ galaradioclub.co.uk

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Moonbounce – A Science for Everyone

4 yagi antennas pointing at the sky

By John Berry GM8JBJ

On 12th May I bounced signals off the Moon.

OK, I’d been bouncing signals off the Moon ever since I put up the antenna system a fortnight before. Just that I didn’t know there was anyone on the other end to decode my 13-character message. Until, that is, on the 12th Mr Potts, callsign NC1I, replied from Massachusetts, USA.

Successful QSO between GM8JBJ and NC1I shown on WSJT-X screen.

Moonbounce (or Earth-Moon-Earth, EME) communication is a very cool thing to do. Just imagine the cred you’d get when next in a bar and you throw that out there when things go quiet.

And importantly, anyone can do it.

Background

The Moon is about 400,000km away (less at perigee, more at apogee). Hence, the flight time for a signal from Earth to Moon and back is about 2.7 seconds. The corresponding round-trip free-space path loss for a signal is a huge 400dBi – no way anyone can bridge that gap. But whilst the Moon is a poor point reflector with a reflection coefficient of 6.5%, it’s also a 3,500km diameter billboard that reflects from all points across its area. The result is a real total path loss of around 250dBi and that’s (just) low enough for radio amateurs to exploit our natural satellite to communicate almost globally.

Basic Kit

Today, almost everyone uses Joe Taylor (K1JT)’s ultra-narrow-band algorithms to code and send a very short message. The message is pared to the bone – it’s even skinnier than FT8. And using his software, WSJT-X, this is sent repeatedly. So, you need a computer, a sound card, and the application. The setup is the same as for FT8, but you’ll configure to use Q65B with a 60-second period.

Video of a transmission via the Moon using Q65B (specks on waterfall and tones in noise) on 432.093MHz at https://hamradio.engineering/moonbounce-eme/

The transmission modulates the audio of a rig and uses upper sideband (USB). The simplest bands for moonbounce are 144MHz and 432MHz. 1296MHz is another option, but above 432MHz you’ll need a high stability reference to hold the frequency steady and 23cm kit gets expensive. Of course, you could do it at any GHz frequency amateur band, but I’m assuming no-one starts at 10GHz or the like. So, you need a VHF/UHF SSB rig.

And then there’s the antenna.

Antenna

There are three options when it comes to antennas: huge, big, and modest. Huge VHF/UHF antennas are for Americans and others with acres of land. They are typically 48 or more stacked and bayed Yagis. Since you must point at the Moon, you can imagine the mechanics and electronics to automatically rotate and elevate 48 Yagis. Radio amateurs with huge antennas are the heavy lifters of the moonbounce world. Without them, novices wouldn’t get off the ground.

The 432MHz array – Frank Potts, NC1I. At https://www.qrz.com/db/NC1I

Then there’s big. ‘Big’ describes folk like me who put up four or more Yagis. That’s easily done. It’s all standard kit. My antennas are on a five-metre scaffold pole. Yaesu and others make az/el rotators, and at VHF/UHF the feeder doesn’t cost a mortgage. Automatic Moon tracking can be done on an Arduino or the like. And many folk in this bracket run 500W.

4-Yagi array at GM8JBJ at https://www.qrz.com/db/GM8JBJ

Finally, there’s modest. There’s a whole movement of folk who use single Yagis and a barefoot rig. And many of those use a lightweight long Yagi mounted on a homebrew tripod. The advantage of this is that you can also avoid spending on a rotator, or on a low noise pre-amp (since you’ll be close to the Yagi feed point). These simple systems are often used /P from some piece of open high ground.

Single antenna portable EME operation at https://www.hamradio.me/operating-tips/eme-on-a-budget-part-2.html

Personal Qualities

There are two. Belief (that you can do it). And patience.

It also helps if you do a lot of research to optimise your kit.

Results

The software does everything for you. But you must do the research to know when is best to try.

Conclusion

The truth is that Moonbounce is not that easy. There are several propagation mechanisms that will thwart your attempts.

First, there’s Faraday rotation. The polarisation of the transmitted wave is sometimes distorted along the path. And there’s nothing you can do about it – save use rotatable antennas, and that’s hugely complex.

Then there’s libration fading. The Moon wobbles. And sometimes the reflected waves received back on Earth create an interference pattern in time with deep fades. There’s nothing you can do but wait till the effect stops.

And of course, it’s stupid to try when the Moon and Sun are both within your antenna’s beam. The Sun adds noise to a sensitive system. But you can just wait till the Moon is on its own.

And then there’s the little issue of few folk listening at any point in time. But you can always arrange a sked on a chat room.

None of these issues diminish its street cred. They even enhance it because they make it complicated.

But here’s the secret. Given the simplicity of the kit, anyone can do it.

Links

More detail from John Berry GM8JBJ https://hamradio.engineering/moonbounce-eme/
John Berry QRZ page https://www.qrz.com/db/GM8JBJ
NC1I QRZ page https://www.qrz.com/db/NC1I
HamRadio.me EME on a Budget https://www.hamradio.me/operating-tips/eme-on-a-budget-part-2.html
WSJT-X Digimode Software https://wsjt.sourceforge.io/

2023 Rally and Open Day – Sunday 22nd October 2023

Lost and Found: Found a pair of glasses with grey translucent frames left at the Canny Components stall. GDARS club has them, contact us by email if they’re yours.

NOTE (21/10/2023): Rally still on! Not badly affected by Storm Babet, just a little soggy and windswept. All weather and flood warnings finished on Saturday.

This year’s Galashiels Rally and Open Day will take place on Sunday 22nd October 2023. Venue is the Volunteer Hall, St John Street, Galashiels TD1 3JX.

Note that this is NOT the weekend of changing the clocks as previous years but is the weekend before to avoid the CQWW SSB contest weekend.

Doors open for general admission at front doors at 11:00 BST.

Disabled/accessible entry and early book-in of Bring and Buy items only at 10:45 BST at rear door.
(Table traders entry at rear door from 08:00.)

Admission will be £2.50 per person, with free entry for under 16s accompanied by an adult.

CASH ONLY at the door. Change will be given but we appreciate having correct change for faster entry.

A sticker will be provided for exit and re-entry.

Confirmed traders (as of 18th October):
Bob McClements GM4CID (Club Stall, Used equipment)
Alan Clegg (valves etc)
Mirfield Electronics
Canny Components
Mick Hunter (Batteries, Memory cards etc)
Tony Kruszelnicki from TK Electronics in Lincoln
Perth Repeater Group
Pete Bates GM4BYF
RSGB (Books, Memberships)
Ken Elliott GM4NTX
Dave Bagshaw
GQRP Club
Michael Wills
Gavin Chalmers GM0ALW
Fraser MM0HCD
DX Maps (Michael Whitehead)
John 2M0YTN
Paul GM0EDJ (Elderslie ARS, SK equipment)

Bring & Buy Stall (50p Book-in charge, 10% Commission up to £10 maximum)
Catering with hot and cold refreshments.

Any trader queries or traders not already booked but wanting to check table availability please email Jim Keddie GM7LUN (mail@gm7lun.co.uk).

Location:
The Volunteer Hall
St John Street
Galashiels
Scottish Borders
TD1 3JX
(Google Plus Code 9C7VJ57R+WV )
(What3Words///practical.diner.voltage)

Access to Galashiels by road from A7, A72 or A68 (via A6091), by bus (bordersbuses.co.uk) or by train (scotrail.co.uk).

Railways On The Air 2023- Whitrope Sat 23rd/Sun 24th September 2023 – GB0WRH

Club members will be taking part in this year’s Railways On The Air event, with a station being set up at the usual place of Whitrope Heritage Centre near Hawick on the weekend of 23/24 September.

The callsign used will be GB0WRH (Waverley Route Heritage) operating on HF bands. Dave MM0HTL will be arriving around 9am on Saturday and setting up, and then along with other members will be operating through the day and evenings until late Sunday afternoon.

All club members and visitors are welcome to come along and see the stations (radio and railway) and help with operating or just come along to chat with us.

The Whitrope Heritage Centre is run by the Waverley Route Heritage Association who have restored a length of track and sidings on the old Waverley line (1849-1969) between Hawick and Carlisle. Further details here: https://wrha.org.uk/about/

Location:
Whitrope Heritage Centre, Whitrope, Hawick, Roxburghshire TD9 9TY
Location: 11 miles south of Hawick on B6399 (Hawick to Newcastleton road).

Maidenhead Locator: IO85PH 00co
55.294320, -2.748944 (55°17’39.6″N 2°44’56.2″W) 1034ft (315m) asl
NGR: NT 52540 00279
Google: 9C7V77V2+MC
W3W:///jousting.windmills.wire
https://wrha.org.uk/the-association/find-us/

Satellite image showing location of Whitrope Heritage Centre carpark

https://rota.barac.org.uk/
https://wrha.org.uk/the-association/whitrope-heritage-centre/

PW 144MHz QRP Contest 2023

On Sunday 11th June 2023 club members went up to our usual spot up the Yarrow/Ettrick “Middle Swire” (aka Witchie Knowe) to operate the station for the Practical Wireless 144MHz QRP contest.

Weather was decent, starting off as mostly cloudy in the morning and a light breeze, becoming less cloudy, more sunny and hotter by the afternoon. The heavy rain through the night before had passed over.

John GM7NVA, Mike MM3NTX and Brian MM7OYD arrived first, then Dave GM0KCN with the antenna and radio. Some chatting between us and playing with HF radio for a time while waiting for Colin MM1APS to arrive with the mast, which he did around 1040 after having to clean up from one of his dogs making a sick mess of his livingroom carpet through the night.

So we got the antenna set up on the mast, and Dave and Colin started operating the contest on radio and logging with John turning the antenna as needed. Some time was spent chasing other stations, and some sitting on a frequency calling CQ. Mostly on SSB but occasionally chasing locals on FM.

John GM0NYD and George GM1OPO arrived around lunchtime and Jim GM7LUN a little later.

Around 1530 (local time) we decided to call it a day as there was only 30 minutes left in the contest and the only stations we were hearing were those we’d worked before. Radio propagation seemed to be starting to fade.

All in all it was a good day operating, the weather held out contrary to earlier forecasts of thunderstorms. Our logs showed 035 as the last serial number used, but on later inspection we found that the numbers went from 022 to 033 then 034 and 035. So 25 contacts made, and a note was included when Dave KCN submitted the logs to the organisers. The logs corresponded to the information sent over the air, so nobody’s logs will be inaccurate, we just omitted serials 023 to 032, possibly after a battle getting the serial 022 copied by the other station.

For those not operating the contest station a chance to get out and experiment with other bands and antennas away from home QRM.

Many thanks to Dave and Colin for operating the station again this year, and hopefully we’ll maintain our streak of Best Scottish Station and Best in IO85.

Photos by Mike MM3NTX, John GM7NVA and Dave GM0KCN.