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Archive for the ‘Training’

My garden grew a flowerpot antenna

February 20, 2025 By: Chris G3YHF Category: Club, Fun, News, Training

No, it wasn’t the Flowerpot Men wot done it!

But my Flowerpot antenna – a ‘single’ band vertical dipole for 12 meters.  Those ‘inverted commas’ are significant – read on!

This is an antenna that’s cheap and easy to build (you just need to be able to strip some coax and solder on a PL259 or similar), and it’s hardly noticeable.  It can be hung from a pole, tree, window, etc.  It doesn’t have radials or a counterpoise.

I like experimenting with homemade antennas, and I wanted to take advantage of this sunspot maximum to work as much DX as possible on 24MHz.  My doublet works quite well, but perhaps a vertical would help by giving me greater low angle radiation?

The Flowerpot antenna is a centre fed vertical half-wave dipole made from coax. 

It comprises a quarterwave radiator made from the centre of a length of coax, below which is a quarterwave of complete coax that is then wound into an rf choke.  The tail of the coax beyond the choke forms the feeder.

The antenna radiates from the top quarterwave section of coax core, and from the outer braid of the bottom quarterwave section.  The choke prevents the outer braid from radiating further along the feeder.

There’s lots of material on-line about how to make one.  

It didn’t take long to measure up some RG58 and expose the inner core at one end.  I then marked a further quarterwave for the position of the choke, which I wound around some 40mm plastic pipe.

I used a dipole length calculator for my measurements.  As I usually do with my antennas, I cut it a bit longer than the calculated figure so I had room for adjustment.

I tied the top to my 8 meter Sotabeams telescopic mast, and pushed the mast up between the branches at the bottom of my garden.  The radiating section cleared the fence on one side and the shed on the other.

The antenna analyser showed there was a dip at about 24.9MHz and an swr of 1.7:1, easily resolved by my rig’s ATU.  To my suprise, there was a bigger dip on 28.5MHz and an swr of 1.1:1 that covered the CW and SSB sections of that band.

So it looked like the antenna wasn’t too long, but too short!  Perhaps this was caused by the close proximity of tree branches?

Two bands for the price of one!

My K3 has dual antenna sockets, so switching between the Flowerpot and doublet on receive, I immediately noticed signals were affected by up to +/- 2-3 s-points on both bands.  Presumably signals ariving by different paths.  There was not much difference in the noise floor.

Now I can alternate between antennas when I put out a CQ call, and also choose the antenna with the strongest receive signal when I call someone.

 

 

 

 

+3000 miles on 1 watt!

February 12, 2025 By: Chris G3YHF Category: Club, Fun, News, Training

Each January it’s Wythall Radio Club’s ‘How low can you go?’ month devoted to QRP operating.

And what great results!  41 countries worked on CW and 66 on digital modes.  Several also on SSB.

Power was restricted to 5 watts CW and 10 watts SSB and digital – although several members thought this was too generous and used even less power!

Wire antennas were used – no beams to boost the dbs!

Kev G4XLO – our own DX member down there in Devon – worked 55 unique DXCC entities using digital modes, closely followed by Martin 2E0XFI (now M0XFI) with 48.  Lee G0MTN worked 59 countries using multiple modes. 

John M6KET topped the CW table with 38 countries.  Meanwhile Neil worked 10 countries using SSB with a mix of HF and satellite.

To add some fun, we ran a ‘miles per watt’ challenge. 

The top scorers were John 2E0XET with a stupendous 3543 miles/watt for his 1-watt CW QSO with Virginia USA and Lee G0MTN’s 713 miles/watt from his 10-watt digital contact with Argentina.

John used his trusty K2 (or was it his KX3?) and dog-leg doublet antenna. Great result!

Down in devon, Kev started off using 10 watts of FT8 but then dropped down to 5 watts for the last 2 weeks to see what could be achieved. 

Here’s his report….. 

“January was a really interesting month for me on the QRP challenge.  I was on 10 watts digital the first couple of weeks and my main bands were 30m and 40m. 

These gave me the normal European regulars as well as the USA one morning. 

The fourth week it all came alive.  I swapped between 5 watts and 10 watts maximum. 

Tuesday, I had a totally awesome day, working China, Japan, Brazil as well as Puerto Rico and Ceuta & Melilla in one day, and yesterday bagged Turkey as well.

Was good to work Belize yesterday – that was my best DX for the week at over 5000 miles away – ones that got away included Venezuela, Indonesia and Brazil although they were quite audible for me in the shack.

It’s been encouraging too to see other members efforts thru the month.”

As well as everyones’ great QSOs, our QRP signals have also been spotted in a variety of locations, including Australia and New Zealand.

Several members have 10 watt maximum rigs, but others have decided to turn down the wick to see what they can work with QRP during the rest of the year.

Just for comparison, here’s our report from last year’s QRP challenge!!

Talk on LF operating – this Tuesday 5th Nov.

November 01, 2024 By: Chris G3YHF Category: Club, Fun, News, Training

What’s happening at the low frequency end of the amateur spectrum?

Dave Pick, G3YXM, RadCom’s LF correspondent, will be revealing all on 5th November at 8.30pm, Darts Room, Wythall House.

All welcome. 

Have some refreshment at Wythall House bar before and after the event.

This is just one of the features in Wythall Radio Club’s new 12 month programme now available here – and on right hand side of our home page.

We’ll post updates as events are added and finalised.  

Photo of Droitwich aerial system courtesy of an anonymous rigger in late 1960s – source and more info here

Is 10 meters open?

September 30, 2024 By: Chris G3YHF Category: Club, Fun, News, Training

Is 10 open today?

That’s the question many of us are asking as we wait for the summer doldrums to disappear and sunspot maximum conditions to reappear.

One way is to put out a call and see if anyone answers. 

When I first got my licence I was told it’s always worth calling on a band that seems dead – it may just be that everyone assumes the lack of activity means it’s dead, when in fact it’s open!

Another way for voice mode and CW operators is to see if they can hear any FT8 burbling on 28.074USB.  If there is, decoding signals may indicate what paths are open.

Then there is the VERY extensive beacon network.  There are beacons on all amateur bands, but 10 meters is very well served.  

Most 10 meter beacons are found between 28.200 and 28.300, with some below and above these frequencies.

Beacons transmit their callsigns in Morse code, and may also give their locator square, power and antenna details.  Listening to them can be good practice for copying Morse code!

There is a recently updated list of beacons here.

Remember to enable CW on your receiver to get the correct frequency!

Early this morning I could only hear the German beacon DL0IGI, transmitting on 28.205. 

At lunchtime, I couldn’t receive this beacon – but instead the Faroe Islands beacon OY6BEC was very strong on 28.235. 

This is part of a comprehensive set of beacons in a radome to protect from the weather – shwon in photo left!

 

 

 

There is a special worldwide set of 18 beacons on 28.200 – the International Beacon Project. 

Each beacon transmits for 12 seconds once every 3 minutes at 100 watts.  There are then 4 x 1 second dashes sent at 100, 10, 1 and 0.1 watts. 

Beacon MapThis lunchtime I could only hear 4X6TU in Israel, and I copied the 100 and 10 watt dashes, I could just hear the 1 watt dash, but not the 0.1 watt dash. 

Beacons may transmit a continuous tone between sending the callsign – so if you hear a tone, listen for a bit and see if a callsign appears.

At least it’s something to do if the band doesn’t have any QSOs on it!

 

 

 

Wythall Wisdom?…. delve into our archive of members’ projects, ideas and activities!!

July 27, 2024 By: Chris G3YHF Category: Club, Fun, News, Training

Do want to know how to use cheap drone transmitter/receivers to get on 5.7GHz? – the photo shows one in operation at Broadway Tower.

Or build a J-pole antenna for bicycle mobile operation? 

Or with more activity on the HF bands as we approach the solar cycle peak, perhaps you’d like to build a small profile ‘C’-beam for 20m using easily available plastic conduit?

It’s shown in the photo left.

It’s all there – and more – in the Wythall Radio Club newsletter archive!  Click here to find the index to articles.

Or brouse the issues by clicking here.

You’ll find lots of invaluable advice, projects and ideas.

We don’t publish a newsletter these days, but try to keep the world informed on this web site.

Or come along to the Club any Tuesday evening or to one of the special events. 

Our location and contact details are on this web site.

 

COMING SOON .. A REPORT ON OUR RECENT EVENING SPENT ON THE LAWN OF WYTHALL HOUSE WITH OUR VERTICALS AND THE VECTOR NETWORK ANALYSER (VNA)

 

Use a VNA to analyse your antenna

July 20, 2024 By: Chris G3YHF Category: Club, Fun, News, Training

Tiny VNAs can now be bought cheaply.

Here’s one Lee G0MTN used to test his rebuilt band-pass filters.

But how can we use them to analyse our antenna systems and improve their performance?

Wythall Radio Club members will be gathering next Tuesday 23rd. July for a practical workshop. 

We’ll be using a VNA to analyse some portable antennas.

We will plot SWR over a given frequency range and display this as a line graph.  And see what else the VNA will tell us!

As usual, 8pm at Wythall House (in the garden if the weather is ok).

Visitors always welcome – bring an antenna!

The Foundation Licence Experience

April 01, 2024 By: john daws Category: Club, Fun, Training

Following Chris’ (G0EYO) previous article on Training  for the Amateur radio Licence, Martin M7XFD describes his journey to the Foundation Licence (and beyond)

WHAT NO CW!! OR HOW I FOUND THE FOUNDATION LICENCE ..OR THE FOUNDATION LICENCE FOUND ME

Martin (left) receiving award certificate from Lee G0MTN

Always at the back of my mind has been the idea of getting licensed as a Radio Amateur.

As a young person I was a Short Wave Listener. My father had been involved in Radar during World War II and at a very young age I discovered a crystal set in his box of ‘bits and pieces’.

We used the metal frame of my bed for the earth, strung a long wire down the garden and with a pair of ex-army headphones rotated the stiff aluminium thing with corroded vanes to pick up the BBC Light Service on the medium wave. Hearing speech and music, with no batteries or electric power involved, was sheer magic to young boy!

Following on from that we had a valve radio that had shortwave that I was able to use and added a long wire antenna. I finally bought an ex-army radio, the size and shape of the top half of a large fridge. A battleship grey Marconi 52 I think. It weighed 50lbs, had glowing valves and UV sensitive dials that also could glow in the dark. I listened to Hams around the world and I wrote to them for QSL cards to confirm I had picked up and heard their signal.

The mighty battleship grey Marconi 52

It was the CW (Morse requirements) that put me off getting my licence (sorry editor)-  [Ed.unforgiveable!!]

Years flew by……….

With a career in electronics which led to computers, I retained my interest in radio and bought an airband radio that had three crystals allocated to Birmingham Airport’s Control tower, approaches and one other: (perhaps I only used two slots as the crystals were expensive.)

Living close to an airport I have updated my scanner and noticed technology changing with the advance of digital radio.

A few years ago I noticed that Wythall Radio Club ran training courses for the Amateur radio Licences and I toyed with the idea of finally becoming licensed.

Time passed. I gained another handheld receiver.

Some of my post-retirement hobbies changed, freeing up time, and in the summer of last year I emailed the club to inquire if I could get involved. As a result Chris G3YHF invited me to a talk at Wythall House in September and a few weeks after that to a ‘Plug and Play’ Open day in the fields at Wythall Community Centre.

G3YHF’s neat portable CW Plug and Play table

I was not the only prospective new member so the talk was on Amateur Radio in the modern world of today. What struck me was that despite the  decline in  numbers of active Hams , the focus has shifted to pursuing  different  ways of doing things in this digital age and the technical challenges within the hobby. I could see this as a way of finding out what would interest me most.

I took my wife to the open day so she could understand better what I was thinking about getting into. She had a good time and could see the range of interests and the camaraderie involved. The fact that every rig and antenna set-up was portable was good for me to see as my main interest is in handheld and portable systems. ‘How much is it going to cost?’, she said. ‘Oh not much’, I replied. ‘There are very cheap handheld radios from China’.

 Neil,G1TZC , taking time out from his satellite dish, reassured me that Morse code was not mandatory and showed me a copy of the Foundation licence manual, explaining me that studying and taking the exam was straightforward especially given my background in electronics. Other Club members encouraged me to have a go and again I checked : definitely no  CW requirement!! 

I sent for the manual from the RSGB the next day.

Wythall Radio Club do not run their own courses anymore as most of the courses have gone on-line, so in September and October  I took the Essex Ham course and passed my Foundation Licence in November last year.

                            

Neil’s Pop- up shack with captive audience . (Martin in there somewhere?)

From contacting a Wythall Radio Club to being licensed took less than three months.

To reassure those that might be thinking of getting into the hobby, even taking the exam itself was a pleasant experience as there is a pre-exam chat with a person who is also a keen radio amateur and the same person is on hand to facilitate the online exam session.

Martin’s current rig

I traded my scanners in for a very good Handheld radio transceiver (right). Even though I could get something much cheaper this was going to be my sole equipment for a while. As you will recall I said I wanted portability rather than a fixed set-up at home

However to get more coverage, with advice from Ian M0LQY, I have subsequently put together a hotspot. With the handheld radio I have three options. I can make contacts directly locally and on the move, via near and sometimes far repeaters, or through the hotspot over the internet. With the latter I can make contacts all over the world, but I have enjoyed most being able to contact  club members directly and via the Wythall repeater. I am also getting to know other Radio Amateurs locally and further afield – sometimes as I pass by on my travels

        MMDVM Pi-Star Rig

It was seeing a YouTube video on a ham using a Handheld radio and a hotspot in his house, contacting the World that was one of the triggers to contact WRC which led on to the Foundation Licence.

To continue to extend my knowledge I am now studying for the Intermediate Exam which is taking longer, but  equally enjoyable.

   For me Amateur Radio has so much a lot to offer.

I am enjoying VHF/UHF and surprising world wide contacts when I want. With the summer coming then HF with a portable set up may be something to try.

Shall I learn morse code? … I am not rushing!! (you never know Ed. !!)

The Full Licence? An Introduction and Guide to the full Amateur Radio Experience- by G0EYO

February 13, 2024 By: john daws Category: Club, News, Training

The full amateur radio experience is within your grasp: read on and discover.

A recent pass of the Full Licence Examination by our Hon Sec. Clive (now M0KNP) got our Training Co-ordinator Chris G0EYO thinking about how wonderful it is that people who have an interest in radio communications, but no technical, engineering or academic training can pass an examination in which some of the questions require them to learn a high level of technical and electronic theory and scientific calculations.

Chris G0EYO has written an article “Achieving the Impossible by Getting That Full Amateur Licence”  where he describes how the structured approach of the Bath Distance Learning Team has got around 1000 amateurs through their Intermediate and Full Licence examinations with their courses which have an award winning success rate.  It is based around a Syllabus which is produced by the Radio Society of Great Britain (RSGB) and approved by Ofcom. Each course ties in the material in Course Books (again published by the RSGB) with the requirements of the Syllabus, so that everything that is examinable is covered by the course.

The team behind the course have put in an incredible amount of time and research to make sure there are no gaps in the training and that each week’s topics tested by a quiz which the students do under timed conditions. The weekly tutorials are optional but are at the same time every Wednesday evening on Zoom. If a student is unable to watch a tutorial in real time a YouTube video of it is available to watch the next day. The tutorial is also supported by a power point presentation and this also available as a PDF to download the next day. 

At the end of the course, the student is expected to have a go at several Mock exams similarly structured to the ones set by the RSGB. It is the tutor’s job to supply the students with worked answers for all the quizzes and mock exams after they have been submitted and to help them with any queries they may have on the questions or course material. The tutor also keeps in contact with the student over his progress and will chivvy them along if they fall behind.

The BBDL Intermediate course runs for 19 weeks and the Full course runs for 20 weeks. Both of these courses call for a serious commitment from the student. In addition to the 2 hour weekly tutorial, you will need to spend another 2 to 4 hours studying each week’s material, preparing for and doing the weekly quiz.

https://www.wythallradioclub.co.uk/?page_id=13341&preview=true

 

YOU WILL FIND THE ARTICLE IN THE LIBRARY/ARTICLEOF THE WEBSITE OR THROUGH THE URL LINK ABOVE

From the Workbench – Kanga Rooster QRP Kit Part 1

December 17, 2023 By: Chris G3YHF Category: Club, Fun, News, Training

Kanga? ROOster? Christopher Robin meets ham radio?

No, just the latest kit from Kanga products.

With Wythall Radio Club’s ‘How low can you go? QRP month looming in January, I thought I’d dig out some of my kit QRP radios. 

Back in 2000 I built the Foxx 3 kit from Kanga Products.  This 1-watt CW rig was crystal controlled on 7030KHz.  It was based on the original 1983 Foxx circuit by George GM3OXX (SK) published in Sprat – the magazine of the G-QRP Club.

Club members have had a lot of fun with this kit.  It’s produced contacts with other QRP-ers around Europe.

However, being a direct conversion receiver mine suffered from considerable break-through from the Droitwich Long Wave transmitter about 15 miles away from my QTH.

Now Kanga have produced an updated version of this design called the Rooster

Like Foxx 3, this is a QRP CW rig for 7030KHz.  However, power output has been increased to 2-watts and there is much improved sensitivity and selectivity due to its active audio filter.  This is centred on 750 Hz with a 500 Hz bandwidth.  

And rather than being mounted in an Altoids tin – the preferred method for Foxx 3 builders – the Rooster is supplied with its own aluminium case.

There are less components and tasks to undertake than when building the Foxx 3 as it uses SMD (surface mount devices) that are pre-installed on the PCB and 20 through-hole parts that the builder needs to solder in place.

The kit arrived with components neatly packaged in small bags so checking they were all there was a simple task.  The 26-page downloadable instructions are in Kanga Products’ usual excellent clear and illustrated format, with instruction for testing each stage after it is completed.

A current limited 12v supply is recommended for testing, but there is probably low risk of damage using a conventional 12v (not 13.8V) supply or battery PROVIDED the location and soldering of components is thoroughly checked after each stage

I use a magnifying table lamp for checking my soldering, especially for identifying any solder splashes that might result in short circuits.

I spent about 3 hours building and testing the kit.  I could have taken less time, but I like to savour the process of construction.  In addition, I had a couple of problems (discussed later) that added some time.  Kanga suggest that the rig could be built in an hour, eg at a Build-a-thon.  It could be with experienced builders, but it would be a rush!

I only had 2 problems.  The first was in testing the audio amplifier, where plugging in the headphones and touching a metal screw-driver to particular components should result in a ‘buzz’.  It didn’t.  There was a weak scratching noise but no buzz. 

Using the circuit diagram and my trusty analogue multi-meter, I checked continuity of the audio section, and it was all OK.

The soldering was very straightforward, so I decided just to press on.  My faith was rewarded as the next task was to install the side-tone components.  When I tested this, it worked perfectly.  So clearly, the audio-amp was ok.

The other problem was my error in installing the diode in the neighbouring holes intended for one of the inductors.  Just lack of concentration.  Unfortunately, I’d trimmed the leads before I realised what I’d done!

However, I use minimal amounts of solder, so it was easy to remove the diode and clear the holes by pushing one of the trimmed leads into the hole, heating it with the soldering iron, and pulling it through with fine-nosed pliers.

Luckily, the holes the diode should have gone in were not spaced as far apart, so I could fit it and have a tiny bit of the leads poking through the PCB for soldering!

In the final desk test I could hear CW using the short length of coax to the dummy load/watt meter as an antenna.  Always a good sign!  And the rig produced 2-watts of RF.

So it worked first time – hurrah!

Now let’s get it on the air!

I plugged in my 40-meter dipole and I could hear masses of stations within the receiver’s passband, but unfortunately they were all engaged in an international CW contest!  I copied stations in 9A, SP, E7 and YO, so that proved the receiver was working very well.  And no sign of Droitwich long wave!

Just to check, I plugged in my Foxx 3 and there it was – a football programme over the top of those CW stations!

The Rooster definitely has a much better receiver! 

It also has masses of audio output but no volume control, so DON’T POWER UP WITH HEADPHONES ON!  I need to wear my ‘phones off my ears to reduce the volume.

As the connections between components are not visible on the PCB, I can’t see how to add a small volume potentiometer similar to the one on the Foxx 3.  Maybe someone at the Club will advise!

What are the lessons from this build?

Some of the components have solder-points in close association, so if your soldering is rusty – or you’ve never soldered – find or scrounge some Veroboard and components and practice.  Check continuity afterwards with a multi-meter set to resistance.

A narrow chisel-type soldering iron tip will work much better than something bigger.  It will provide more control where there are components near to each-other.

A temperature-controlled iron will also help with getting enough heat onto the big lugs of the antenna socket so that they have a good electrical and structural connection.

A dummy load is required.  One can be built from resistors, or there are also dummy load/watt meter kits for QRP rigs available.

The fittings that go through the front and back panels (eg DC input, RIT) must be aligned with the edge of the board.  I used the panel to make sure they were in the right place, and a bit of tape helped hold them in place until the first lug was soldered.

Overall, this has been a very enjoyable little kit to build.  It’s priced at £37.99 plus P and P and given it includes a metal case I think that’s a reasonable cost. 

It’s a good first step for anyone starting out with construction, and could then lead to the QRP Labs QCX-mini one band, fully featured CW rig (not crystal controlled!) currently at £44 plus £16 for the case plus P and P.

Once I’ve had a play with the Rooster on 7030 I’ll post an update on how it performs.

 

Signals from Space with a Handheld

September 22, 2023 By: Chris G3YHF Category: Club, Fun, News, Training

The ISS (international space station)’s digipeater can be heard with a 2 meter handheld when one of the ISS passes is overhead.
 
And if you can connect your 2m FM rig to a computer, you can send and receive messages through it – and receive the special ISS QSL card!
 
Now is a good time to try as the ISS is passing over the UK at a good elevation twice most early evenings.
 
Find the ISS pass times HERE – remember to add 1 hour as times are UTC.  Ideally, look for 70° or 80° elevation when ISS is passing close to overhead.
 
The live ISS locator is useful to track its position and digipeater footprint.
 
Tune to 145.825 FM with squelch OFF and listen for the short bursts of data.  You will only hear these for a couple of minutes during each pass.

The contents of data packages received by the ISS are instantaneously retransmitted by the digipeater and received by one of the SATGATEs where they are automatically uploaded to the ARISS web site HERE along with the list of stations whose transmissions were received and maps of their locations.
 
Only short messages can be sent, and here are some examples from earlier this evening:
 
00:00:01:12 : G0GOO]CQ,RS0ISS*,qAR,ED1ZBF-3::G7HCE :QSL and 73 via ISS
00:00:01:32 : G6UQZ-1]APDW17,RS0ISS*,qAU,DO6DD-10:!5204.75N/00034.94EyPHG200073 de Andy in Clare, Suffolk
00:00:01:39 : G3YHF]CQ,RS0ISS*,qAU,DO6DD-10:=5226.15N/00152.30W-IO92BK 73 de Wythall RC {UISS54}
00:00:01:41 : RS0ISS]0P0PS3,APRSAT,qAR,ED1ZBF-3:’v&l SI]ARISS-International Space Station=
00:00:01:42 : G7HCE]APK004,RS0ISS*,qAR,F1ZRP-3::G0GOO :Copy 59{5
 
The highlighted message is the one I sent this evening that was received and retransmitted by the digipeater after 6 or 7 attempts!
 
It gives the age of the retransmission, my call, the callsign of the digipeater – RS0ISS* is the Russian ISS call sign, DO6DD is the German SATGATE station that received and uploaded the packet to the ARISS site, and then there is my message: my APRS location in lat and long and Maidenhead square, and a few words of greeting!  The ‘ – ‘  instructs the ARISS site to add my QTH to its map.
 
Occasionally, the digipeater is temporarily shut-down for spacecraft operational activity like a spacewalk.
 
To send a message through the digipeater, connect a rig that can transmit 2m FM to a computer.  The rig will need an internal soundcard or if not use an interface like Signalink.  
 
I use my Yaesu FT7800 mobile rig on 5 watts with Signalink and a collinear. 
 
I also have an old Kenwood TH-D7 handheld with internal TNC and APRS functionality – this puts out 2.5 watts and I’ve been received by the digipeater again using my collinear.
 
Then download and configure UISS , which has been designed for communicating with the ISS digipeater.  Configure so it talks to your radio.  Then set ‘path’ to ARISS and add your APRS data and a short text.
 
There’s lots of on-line advice on how to set up UISS and use it to send a message – e.g.  on the AMSAT site
 
DON’T USE HIGH POWER!  ISS is line of sight, so 5 watts to a collinear will work very well.  High power will put exessive demand on the ISS rig’s batteries and block other stations from using the digipeater. 
 
The digipeater is simplex and lots of European stations will be calling so it may take several goes to get through.  On the current west to east trajectory of ISS, it’s best to try early on a pass before it’s in range of continental Europe
When your message is retransmitted by the digipeater, it will often appear as a highlighted message in UISS.
 
However, you may not receive this retransmit due to fading or other factors causing even one bit of data to be lost, so affecting the checksum.  
 
So it is always best to search for your call on the ‘Amateur Radio Stations heard via ISS’ page at ariss.net as a ground station operating a SATGATE may have received the retransmission and automatically uploaded it to the ARISS site.
 
Wythall Radio Club members had a go with conducting a brief QSO using the digipeater a couple of years ago, and two of us used it to score points in our Christmas Contest.  
 
Have fun!