Our 2022 Open Day and Rally is booked and being organised for Sunday 30th October 2022.
Read more »2022 Open Day – Sunday 30th October 2022 – Confirmed Traders
Posted by gdars
on August 29, 2022
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Club night – Colin’s 2m Cubical Quad Antenna
Posted by gdars
on July 25, 2022
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Everyone needs a nanoVNA for testing antennas!
He is now working on a similar antenna for operating on the 4m band (70-70.5MHz).
50MHz Sporadic E by John Berry GM8JBJ
Posted by gdars
on June 21, 2022
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A first (for me)
The Sporadic E (Es) season has been pretty muted this year. Maybe it will improve. It’s followed a typical trajectory with openings allowing paths from central/southern UK to central and southern Europe. But for us at 55˚N, it’s been more meagre.
As a newcomer to modern data modes, one event did stand out, during one 50MHz Es opening.
Background
Es propagation (via the E region at around 110km up) is caused ultimately by the Sun. Isn’t everything? In our summer, the Earth tilts such that the Tropic of Cancer (about 23˚N) is facing the Sun. The ionosphere at 23˚N gets cooked and electrons are produced in sufficient density. If incident at shallow angles, VHF signals may get returned to the Earth from reflection points at that latitude.
Up at 40˚N, above Greece for example, the cooking is a bit less efficient, and the electron density is lower. It does however densify from time to time because of electron movement. The cause of this sporadic densification is both complex and unclear, but two of several likely variables are atmospheric tides and waves, themselves caused by interaction between the Earth’s and the Sun’s geomagnetic fields.
The resulting Es propagation gives rise to a feeding frenzy on 50MHz data modes, with southern operators making the most of intra-regional single (1E) and two-hop (2E) paths. Great if you’re in the thick of it and want to clock up numbers.
Up at 51˚N (London), operators exploit reflection points about 600km away for a 1,200km path to central and Eastern Europe. And less frequently they exploit more distant reflection points, down to central Africa, the Middle East, and the like for a 2,000 to 5,000km twin hop. There’s often plenty to be had in early afternoon on a good summer’s day.
For us at 55˚N, it a different and more frugal picture. The sun’s cooking is less intense at reflection points over the south of England, and the incidence of usable reflection points is lower. We can participate a bit in the feeding frenzy, but any contact east-west and north is normally DX indeed.
7th June 2022
The day started normally enough with FT8 contacts in southern and central Europe with southern UK stations participating.
The efficiency of the reflections grew to a point at about 2:00pm where reports (of received signal power above channel noise) passed +10dB. For reference, FT8 is 23dB more effective than SSB phone and that’s why it’s so popular – distant contacts are possible on FT8 when they’re just a dream on SSB.
With such a good positive signal power I guessed a voice call might be possible. So, I tuned to around 50.150MHz, the SSB calling frequency. To cut a long story short I was working station after station across Europe on phone with signal reports of 5/9+20dB.
It occurred to me that if this was the intensity of the ionisation around 45-50˚N, it might have improved too at more northerly latitudes. As the afternoon bore on and the Earth turned, reflection points in mid-Atlantic might support northerly trans-Atlantic QSOs. So, I excused myself from the phone melee, fired up WSJT-X and turned the beam WNW towards Canada.
PSKReporter showed that I was lighting up stations on the east coast of the US and Canada. The PSKReporter screen is shown adjacent.
For those not familiar with PSKReporter, stations using WSJT-X can select a reporting mode. They will, on receipt of a data message from another station, telegram a central server via the Internet, reporting the received signal level. The time of receipt will be flagged on the PSKReporter web site. Those flags are shown in the adjacent image with the time since signal receipt.
Now, a couple of things to note. First, just because my signals are flagged as received does not mean the station doing the receiving is manned. Many amateurs leave their kit on to provide this reporting as a service. And, observing the FT8 signals, it was clear that many data messages were only being partially received, let alone decoded. This was sporadic E at its most sporadic.
As the minutes passed, the received signals to the US and Canada improved and reporting moved westward, starting at Nova Scotia, and ending around Ohio.
At 3:17pm I managed to exchange with WA1NLG in Massachusetts at received signals both ways of +4dB. Then the opening faded and received signal levels diminished. A first for me, then it was all over.
Those in the southern lands between 35 and 45˚N were still managing QSOs with the US at parallel latitudes. But for Scots at 55˚N, it was over.
At +4dB, I could dream about a phone contact to the US on 50MHz! Just a few more dB needed. Maybe next time.
8th June 2022
So, what happened the next day?
The day started in a similar way. Legacy ionisation was allowing some Es contacts, and even receipt of signals from the US and Canada. But few operators were completing any contacts. The distant stations’ CQs could be decoded, but then they faded. Incomplete QSOs were rife.
Again, Sporadic E at its most sporadic! In short, it was a dead duck.
So, what was different between the days?
People speculated on chats. Whatever caused the densification of electrons on the 7th had changed or was absent the next day. The electron clouds had dispersed. One thing different was that we were experiencing huge occurrence of lightning storms in northern hemisphere mid latitudes after a period of extensive high pressure over southern Europe.
Now, weather occurs in the troposphere up to around 12km. The E region giving Es is around 110km – above the weather and in the thermosphere. But lightning storms do cause upward turbulence. And they might be just the sort of occurrence to disperse clouds of densified electrons. Maybe that’s an explanation. More reading needed!
Post Note
On a QSO with GM0OQV he reported that on the weekend of the 11th and 12th June it had been the ARRL VHF contest. During that, he had several FT8 contacts with USA and Canada – and several phone contacts too – all on 6-metres.
Just my luck to have been doing something else that weekend!
John GM8JBJ
PW 144MHz QRP Contest Sun 12th June 2022 Report from MM3NTX
Posted by gdars
on June 16, 2022
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Myself (Mike MM3NTX), my dad George (GM1OPO) and Brian (MM7OYD) got to the site at about 0915 local time, coming through some light rain showers on the way from Peebles.
The wind wasn’t as strong as expected at the top of the hill.
We manoeuvred the vehicles and initially mounted the antenna pole base under the van wheel, but the poles were going to be too close to the (brand new) van bodywork when swinging in the wind, so we switched to mounting the antenna base under the wheel of dad’s Honda Jazz, then built up the antenna and mounted it on the poles.
Nigel (GM7GRH) arrived with a car battery and cable for connecting to the Yaesu FT-991A. We did have some 7Ah sealed lead-acid batteries but with a receive minimum current draw of 1A a bigger battery would be more suitable.
We set up the table and chairs in the back of the van, and set up the FT-991A. Slight panic when pushing the power button didn’t do anything, but then we found the crocodile clips weren’t gripping the battery terminals tight enough to get contact. Small adjustment and we had a lit screen and familiar SSB background noise through the speaker.
Tuning around 144MHz we immediately we started hearing stations and made our first couple of contacts, including a 5/4 report from the JO00 square East Sussex/Kent. I did like when finishing our first QSO, another station called in “GM4YEQ, can you QSY to .350?” and gave us another good QSO in IO84 (5/9 both ways). If only they were all that easy!
A few other contacts were heard that we weren’t able to get contact with, but otherwise the band seemed really quiet. I expected there to be dozens of stations heard while the antenna was pointing roughly south or southeast. So the bands seemed disappointingly quiet. I thought after previous days of VHF E-skip there’d be signals from all over England and even into Europe.
It is annoying when you’re 5 or 6 QSOs in, and then every time you hear a signal and zero-in on it, it’s a callsign you’ve already worked. Nothing heard while pointing north or northwest into the Highlands or even Edinburgh, Fife or Glasgow.
A couple of instances of hearing a QSO then both stations disappear into the QSB then never come back. We also heard what sounded like 2 simultaneous QSOs on the same frequency.
I did spend some time sitting on a frequency and sending CQ calls but nothing heard back.
It did really help that we were able to operate from inside the back of the van when there were frequent, sometimes heavy, showers and some gusty winds at the leading edge of the showers. It also saved any logging paperwork being blown around in the wind or smudged with raindrops.
Logging was done on paper, with a scratch sheet for taking the initial details of the QSO, then those details copied into the main log sheet. This meant that I could listen to a station talking to someone else and note down their callsign, locator and signal strength all ready for when I had my own QSO with them (if they heard me) and it just meant confirming the details I’d already overheard, adding the signal and serial received from that station, then adding the time logged.
I did have a logging spreadsheet on my tablet but ended up not using it as paper worked fine. If we’d had a higher volume of contacts (or daresay a pileup) I’d have switched to the tablet.
Operating with the Yaesu FT-991A was easy once I’d figured out the menu options for audio filtering. The waterfall display wasn’t as useful as I’d hoped as only the strongest of signals were showing up on the display and no sensitivity adjustment available (unless there was a setting I missed), so it was back to mk-I earhole and listening to the whistles of passing signals while tuning around. The voice keyer was useful though, recording a CQ call with callsign in letters and phonetics with locator square, then just needing to hit a button to send the call, leaving a few seconds to listen for any reply. It saved the voice and also avoiding tripping over words when repeating the same phrase over and over again hundreds of times.
Around 1330 we started to transfer stuff to cars and pack up Brian’s FT-991A as he had to leave early for family duties, so we moved to the Honda Jazz dashboard and my dad’s Yaesu FT-817 running off 7Ah SLA battery. Still sheltered from the continued heavy rain showers and wind gusts. No voice keyer so manual CQ calls done every minute or so for a while when not scanning around the band. I did send some CQ calls out on FM simplex channels in case any local club members were scanning around but with no response. Maybe using a non-directional vertical antenna would have been better for FM.
We didn’t make any more contacts after switching to the FT-817 (or even the last 20 minutes with the FT-991A) so by 1530 (local time) we decided to pack up while we were in a dry spell between showers, so the radio and antenna was dismantled and packed into the car.
It was disappointing that we only made 9 contacts, in 7 squares but I got my first experience operating the club station in a contest. Usually I’m helping with logging or just assisting as other members set up and operate the station but this time I was operating so I learned a bit about that. It was also recent club member Brian’s first experience seeing the club station operating a contest, giving him some new knowledge and ideas in mobile operating and amateur radio in general when seeing my dad doing some HF operating with the Yaesu FT-817 and Alinco DX-70.
Many thanks to Brian for letting us use his new FT-991A and his even newer van for working in, my dad George for the antenna, poles, and the FT-817 backup transceiver, and Nigel for the big battery with cable, and guidance for when I was on-air, and basically everyone for helping get everything set up and running with no hitches. We even remembered to plug the coax onto the antenna before erecting it this time!
It would have been better with bright sunshine and no wind and we’d been able to operate outside, and of course if band conditions were more favourable, but it’s always good to get out operating and catching up with with club members for the day outside our normal 2-hour meetings on Wednesday evenings.
Hopefully with the RSGB VHF field day at the start of July we’ll have better weather, better propagation and more club members out with us.
Mike MM3NTX
Location: Yarrow/Ettrick Swire IO85MM
Rig: Yaesu FT-991A (also Yaesu FT-817 but no contacts made)
Antenna: 2m 7-element ZL Special Yagi
Unfortunately didn’t get a chance to take photos of the station in the back of the van.
PW 144MHz QRP Contest 2022 – Sunday 12th June 2022
Posted by gdars
on June 11, 2022
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Some members of the club will again be going up the hill to operate a portable station for the Practical Wireless 144MHz QRP contest on Sunday 12th June. We will be using the callsign GM4YEQ/P.
The contest runs between 0900-1600 UTC (1000-1700 Local/BST). We’ll likely be on site from 0930 (local) if not slightly earlier for setting up.
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