Category Archives: 144MHz

OId news…

Wow! I haven’t posted for quite a while, perhaps I’ve too busy actually being “on the air”, rather than spending all my time on various forums moaning about FT8 or some other nonsense? Anyway, I’d better generate a few updates and here’s the first.

First of all, of course, is the fact that I’ve finally made a 2-way qso with D4 on 2m. D4Z, in fact, operated by Mark, EA8FF, on-site in Cape Verde, HK76MU. This was on 5th August 2018 at 16:15z, using CW at 4163km. I was extremely happy to make this contact: it’s been a personal ambition of mine since I first became interested in VHF way back in the 1970’s – an awful long time to wait! At one time I even had genuine thoughts of living on Cape Verde to explore the V/UHF possibilities, although that never came to fruition…

Video or audio at both ends are here:

As for the qso, it was only a matter of time, having heard the beacon so many times in the past. For that very same reason, I personally didn’t make much of a “song and dance” about the fact it was, at that time, a distance record; I had no doubt it would easily be exceeded, sooner or later. Despite that, our qso did receive a lot of publicity, which was a great help in encouraging others to be aware of the possibilities. Since that day the distance record has already been extended several times by D4Z and D41CV, and it will be again, thanks to the great efforts of the team at D4C. I continue to be excited at just how far we, as a V/UHF community, can push the limits and will strive to make sure we do just that!

My own target now is to work towards a D4 qso on 70cm. Rumours are that would be a world record, not that I care ūüėČ

Contest + Meteors + SDR = Fun!

The first weekend of May each year hosts a Europe-wide VHF/UHF contest. It’s one I always look forward to: there’s a decent chance of tropo on some of my favourite bands (unfortunately not this year); a slim chance of Es (definitely not this year!); and, most reliably, it’s around the peak of the Eta Aquariids meteor shower.

Eta Aquariids meteors are quite unusual because they are relatively swift (at 66.9km/s) compared with many other shower meteors. When seen visually, they leave long and persistent trains in the night sky. In a similar fashion, from a radio perspective they often result in long and intensely strong “bursts”. Combined with a decent peak hourly rate of 40 and a lot of QRO, well-sited stations all over Europe, this can make for some interesting listening! This year did not disappoint with many bursts heard on 144MHz, some lasting tens of seconds.

A step up from simply tuning around searching for meteor-scatter bursts is to use a Software Defined Radio (SDR), with appropriate software, to record a portion of spectrum to hard disk for a period of time. This data can then be viewed after the event, tuning across the recorded spectrum as if it was in real-time. As an example, I used Simon Brown’s excellent SDR-Radio suite (Version 2.3 in my case) to do just that at various points through the weekend, capturing several very good meteor bursts.

Included below is a video of me using SDR-Radio’s data file analyser to play back signals captured during one good burst on 144 MHz, which I’ve annotated with information about each station received, wherever possible.  Enjoy!

This data was captured in IO51vw using an 11el F9FT antenna at 6m a.g.l., azimuth 095 degrees, a mast-head preamp into an active 0dB loss splitter, feeding an RTL SDR dongle on one port. The recorded spectrum was originally 1MHz wide, centred at 144.280MHz, but I’ve used the data file analyser to zoom in such that the spectrum now covers from approximately 144.150 MHz to 144.410 MHz.

 

More transatlantic aurora

On the 17th December, shortly after 09z, there were two solar coronal mass ejections (CMEs) in rapid succession, both of which directed at least some of their ejecta towards the Earth. This was fair warning of the possibility of aurora due some time on the 19th, depending on exactly how fast the material was traveling. The strength of any aurora would also depend on the alignment of the Interplanetary Magnetic Field; for maximum effect we would need a strong southerly component.

As anticipated, the CMEs passed the ACE spacecraft at 13:05z on the 19th, hitting the Earth approximately one hour later. The good news, from our point of view, was that the IMF had a significant southerly component for much of the time, resulting in excellent coupling of the CMEs into the Earth’s magnetic field causing¬†a nice strong aurora!

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Tropo on the edge…

It’s been¬†some months¬†since we’ve seen any sort of decent tropo opening on VHF/UHF, in this part of Europe at least. However, there really was no excuse for being unaware of¬†this one in advance because the¬†forecasting websites (F5LEN¬†and Hepburn) had been¬†predicting something nice for the end of September for at least week prior. It turned out to be exceptional!

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Super Atlantic tropo!

I’d been keeping an eye on the F5LEN and Hepburn¬†Atlantic tropo forecasts prior to the 20th of May¬†because they¬†looked promising for good propagation towards the south:

Hepburn North Atlantic forecast 06z May 20, 2015

Hepburn North Atlantic forecast 06z May 20, 2015

F5LEN Atlantic forecast 00z 21st May, 2015

F5LEN Atlantic forecast 00z 21st May, 2015

Lots of bright colours over much of the North Atlantic! There looked to be some possibility of a repeat of Dave, PJ4VHF’s incredible¬†reception of the Cape Verde beacon, over a distance of some 4700km (and perhaps further?), as well as a north-south path touching on Ireland.

Up until lunchtime on the 20th there was nothing¬†other than a slight¬†enhancement on my AIS receiver (a useful propagation tool at 162MHz, online at MarineTraffic) showing ships slightly further south of Cork than usual – certainly nothing exceptional. I wasn’t even hearing the stalwart ED1ZAG beacon in IN53 but the forecast maps were marginal for that direction.

At approximately 14:35z, a weak cw-keyed signal appeared just very slightly above 144.436MHz, rapidly becoming strong enough to identify as D4C in HK76mv!¬†The Monteverde Contest Team’s beacon is¬†at a distance of some 4165km from EI3KD, with a tolerance of five¬†kilometers or so, which probably makes it the furthest tropo distance yet heard from within IARU Region 1.

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“St Patrick’s Day Aurora”, 144MHz

The aurora of 17th March 2015, St Patrick’s Day, was a superb event: It was good enough to propagate signals on 50MHz across the Atlantic, which I found particularly interesting. Unfortunately I haven’t had much time to get anything in the blog about conditions on 144MHz, so here’s an effort to get at least something recorded!

The QSO map for 2m looked like this:

"St Patrick's Day" Aurora, 144MHz

EI3KD (IO51vw) QSO map for 144MHz during aurora on 17th March, 2015

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Cloudy, with a chance of DX – super tropo.

A baby 70cm station is born, ready for action!

EI3KD antennas

2m (11el F9FT) and 70cm (19el F9FT) at EI3KD

Some months ago I added a 432MHz 19el F9FT antenna to the mast (approximately 4.5m a.g.l.), with the help of G4CLA – thanks Pete! My¬†FT857D is capable of 20 Watts output on 70cm, but I did find an old sspa that, with a reduced drive from the rig, bumped it up to a massive 30 Watts! Every decibel¬†counts, right? Anyway, the sspa’s built-in preamp was probably a small improvement over the rig’s front-end. Even with such a small set-up¬†I’ve managed to give away a few points in the RSGB UKAC 70cm contests, and also had a few DX contacts during brief spells of enhancement. I also have a higher power sspa to modify for 432MHz, but that’s another story.

Since added the 70cm antenna¬†I’ve been looking forward to a decent tropo opening, and early February wasn’t going to disappoint! Apologies for the length of the blog that follows, but it was an exceptional tropo opening…

Worked and heard maps 8-12 Feb 2015

144MHz worked and heard, 8-12 Feb 2015

144MHz worked and heard, 8-12 Feb 2015

432MHz worked and heard, 8-12 Feb 2015

432MHz worked and heard, 8-12 Feb 2015

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Update…

I thought I’d better post an update, having not posted anything for a while; the reason being that not a lot has been happening!

The Eta Aquariids meteor shower peaked on the 6th of May, producing some fine, long meteor bursts: The best I heard was one from DF1JC (JO31) on 2m that apparently lasted for over 130s at S9, and there were a number more from various people lasting 20/30s. The one downside of this shower was quite a low meteor rate, so we¬†had to be patient especially over the longer distances. We’re actually at the bottom of a twelve-year cycle for this shower, so the rates should only get better over the next six years. I didn’t work anything sensational, but was very happy to complete with the Camb-Hams DxPedition, GS3PYE/P (IO68ul) for a new square.

The much-anticipated Sporadic E (Es) propagation has started in Europe, giving a few lucky people 6m links into TEP and F2 propagation further south. The only thing of interest heard here recently was the ZD8VHF (II22TB) beacon on 50.0325MHz at around 21z on 5th May, via an Es link into evening TEP, weak but audible:

East and Northern Europe have had the first Es opening of the year on 2m, on the 13th of May Рone of the favourite dates each and every year!

On 2m EME I’ve worked a few new initials (now up to 114), including I3EVK (JN66) and IK7EZN (JN90) both in new squares for me. However, a¬†highlight was a contact with the Team Athletico expedition to Senegal, 6W/PE1L (IK14jp):

6WPE1L qso EI3KD, 2m EME, JT65B

6W/PE1L qso EI3KD, 2m EME, JT65B

A lot of concentration and patience is required for this sort of EME contact, given I was trying to work a modest, albeit highly optimised, two-yagi station with my single short 11 element yagi: I missed a few opportunities at the start of the expedition because, for a few days, they had a local obstruction causing a minimum 7 degree horizon, which meant the moon was already above my ground-gain peaks by the time it “rose” for them. However, when I began to get common windows I concentrated on them at every opportunity. I heard/decoded the expedition quite a few¬†times but was, unsurprisingly, unable to break their pileup during the very short times¬†when my ground-gain was enough to see them – a maximum of two periods each about twenty minutes long after moonrise, with no possibility at moonset due to local noise. In the end the time spent paid off and¬†after many¬†failed calls¬†and one or two near misses we finally made a fine contact. The team can’t be thanked enough for their unsurpassed¬†dxpedition and operating skills – thanks once again guys!

Hopefully my next update will be reporting a massive 2m Es opening, or some extraordinary tropo – we live in hope!

Aurora!

Who’d have thought, 11 (or even 22) years ago, that aurora would be so rare this time around? There have been hardly any openings this far south, but we’ve had a couple in recent times.

On February 23rd, I worked Clive, GM4VVX in IO78ta at 17:38z. For some reason Clive was hearing me a lot better than I could hear him – I do have a lot of band noise the nearer north I beam, but it still seemed non-reciprocal?

On February 27th we had a slightly better opening. I worked a couple of Gs and GMs, but best dx was to SM4IVE (JO79sd/1682km) and SM7GVF (JO77ga/1565km) – all QSOs at a heading of 035 degrees.

The signals from SM7GVF were quite strong at times:

SM4IVE was weaker but still peaking around 54a. I haven’t found him on my recording yet (it may have been off at the time) – if I do I’ll add it to the playlist.

A small milestone…

Conditions have been poor and the weather has been terrible, but I reached a small milestone: I completed a moonbounce QSO with my 100th unique station (initial), and have since gone on to work a couple more. I’m happy with that, given my ridiculously small antenna and the fact that I’m limited to moon-rise only. The low height of the antenna above ground (approximately 6 or 7m) results in only two usable ground-gain peaks (around 2.5 and 12 degrees elevation), so my windows of opportunity for EME are indeed very limited!

I’m sure there are people with similar systems to mine that have never considered EME, perhaps thinking their antenna is too small. Please do give it a go! As an incentive, here’s a few statistics from my 102 unique EME stations:

  • Number of EME DXCC: 34 (15 are unique to EME)
  • Number of EME Squares: 88
  • Number of EME Fields: 22
  • EME best dx:¬†ZL3TY, RE57OM, 18956km

I’ve also heard quite a lot more stations that I’ve not yet worked, including a better ODX, so there could be more to come…

I arbitrarily chose the 100th initial as a target to reach before making any changes to the system. Now that’s done I can think about what to do – current plans are to add 70cms, and perhaps add elevation and/or a second 2m antenna.