Practical WirelessDecember 2024的目錄

Itend not to be an early adopter of radio products, as on a few occasions now, I have become disappointed with early performance of some radios until firmware updates come along to fix them, in some cases taking as long as a full year to get the functionality promised at the outset. I had been aware of the Malahit brand for some time and conducted plenty of due diligence via social media groups dedicated to the brand, and in particular the DSP2. The team behind the product are Russian, but since the invasion of Ukraine and Western sanctions, they decided to licence their products to the Chinese to manufacture. This move, clearly to allow the continued sale of their products, troubled me somewhat as I had a personal dilemma over…

DX Féile [1] is the brainchild of Dave Deane EI9FBB and the members of the EI DX Group [2]. The first one being held in 2017 on Inis Mór, Aran Islands (EU-006). Then in 2018 they returned to Inis Mor as the last stop on their Irish Islands IOTA Tour 2018 programme. They had two stations on the air using the call EJ1D, with approximately 25 attendees and it was decided to hold the event each year. 2019 was to be the last time at Inis Mor before the pandemic closed down all travel and gatherings. It resumed again in 2022 at the Shannon Springs Hotel, Shannon. This year it was held at the Temple Gate Hotel, Ennis, County Clare, with over 50 attendees from around Ireland and the world.…

1. Who lived at Villa Griffone? 2. 18100, 21074, 24915. What comes next? 3. Russia is made up of how many DXCC entities? 4. What major amateur radio operating event will take place in the UK in July 2026? 5. What do callsigns 1A0C, S01WS and Z61DX all have in common? 6. What is the joint claim to fame of DL8JJ and G0VJG? 7. A single “dah” is the only thing that separates the names of two countries when spelt out in Morse code. What are they? 8. What, in the world of amateur radio, is an RIB? 9. If you had a single licence to operate from London, Poland and Paris, what would be the prefix of your callsign? 10. When would it have been possible to make contacts…

It’s some time since I last looked at satellites. Quite a lot has happened in the meantime. Probably the most noticeable event has been the arrival of QO-100 (also known as Es’hail-2) on the satellite scene. Nearly all amateur radio satellites orbit the earth. They require a means to predict when they will be above the horizon at your location. The pass duration will typically be under ten minutes, although some are much longer. Unlike the orbiting satellites, QO-100 is in geostationary orbit. This means that the satellite stays in the same place in the sky all the time – above the Democratic Republic of Congo on the Equator. This has the big advantage of not needing to predict when the next pass above the horizon will be visible –…

For wireless coverage of the 1953 Coronation on 2 June, microphones were grouped at a number of strategic locations, each having a temporary control room to house equipment and engineers. The microphone outputs intended for transmission abroad were routed to a main control room installed at the Colonial Office while those for the BBC’s transmitters at home were connected to another main control room in Westminster Abbey. Audio outputs from both centres were sent to Broadcasting House for distribution to their various destinations, most of them going via BBC and Post Office transmitters, and others by landline to the Continent. There was a good deal of duplication of equipment and circuits to guard against possible breakdowns, although in fact, none of it actually proved to be necessary. Vintage coronation television…

ORLANDO HAMCATION 2025: The Orlando Amateur Radio Club is hosting the 78th Annual Orlando HamCation on Friday, Saturday, and Sunday, 7-9 February, at the Central Florida Fairgrounds and Expo Park. HamCation is the second-largest ham radio convention in the world, with the inaugural event dating back to 1946. Since the first event, HamCation has continued to grow, with a record attendance for all three days in 2024 reaching 25,321. The HamCation website offers easy-to-use features and a ticket purchasing system. Those who want to attend can purchase tickets, SWAP tables, tailgate spaces, and make RV reservations online now. The user-friendly site also provides information on HamCation activities, vendors, and hotel partnership discounts.  www.hamcation.com PROPAGATION: “Solar Cycle 25 likely reached the highest sunspot number yet - a value of at least 299.…

Although this column is being completed in mid-October, it is the December issue of PW, so I would like to wish all readers a very Merry Christmas (or happy Hanukkah, as appropriate). I hope Santa brings you that new IC-7760, FTdx101, TS-890S, or whatsoever you wish! There is even more HF news than usual this month, so I’m grateful to the Editor, Don G3XTT, for finding an additional page for HF Highlights so as to squeeze it all in! Two new DXCC entities on the horizon? On 3 October the UK government announced that it will be ceding sovereignty of the Chagos Islands, which includes the UK-US military base on Diego Garcia, Fig. 1, and handing control of the islands to Mauritius. According to the BBC news website, a joint…

I am pleased to kick off this month’s column with news of another AN-SOF Antenna Simulator update. Version 9.5 has now been released with a number of useful new features, quoting the press release: Simplified Polarization Analysis: All radiation pattern metrics—power density, directivity, gain, etc.—are now easily decomposed into Vertical (VP), Horizontal (HP), Right-Handed (RHCP), and Left-Handed (LHCP) components. A new toolbar on all graphs lets you quickly toggle between these polarisation components, making analysis more intuitive than ever. Enhanced Geometry Input: Helix Primitive Updates: Design axial mode helices and QHAs (Quadrifilar Helical Antennas) more easily by entering values for Diameter, Pitch Angle, and Wire Length. New ‘GB’ Command: Import and export wire arcs using this command, which is more versatile than the traditional ‘GA’ command and simplifies the modelling…

When the summer edition of the G-QRP club’s SPRAT magazine arrived I was immediately taken by the image on the front cover of a transceiver that was unfamiliar to me. It was the subject of a restoration by Guy Marchal ON5FM and after reading his article I decided I had to own one. The radio was a Ten-Tec Argonaut 509 and I learned that it is rated at 2 Watts minimum in CW and SSB modes from 80m to 10m with a very capable receiver, Photo 1. I quickly found the Classic Argonauts section on groups.io and started asking questions. This produced a contact from an SWL in the UK who had one that he hadn’t used for some years. A deal was done and I was the proud owner…

Amateur Radio Exams Dear Don, As the Training, Development and Examinations Officer for my local club, The Halifax & District amateur Radio Society (HADARS), I was surprised and dismayed to receive an email from the RSGB, that will no doubt come as a shock to many other Amateur Licence Training Schools everywhere. The email contained an announcement by the RSGB that paper examinations in clubs and examination centres across the UK would be discontinued on 31 December 2024. The RSGB, were quick to claim that the online examination system that they imposed during the Covid lockdowns had been a ‘Huge Success’ (which of course it will be if you offer people very little alternative choice!), but it seems the decision has been made without much consultation with Clubs and Examination…

The new Pro version of the Anytone AT6666 10m mobile transceiver builds off of their popular design with increased power output, noise reduction technology, programmable mic button, and TX bandwidth settings. The AT6666 Pro boasts 80W (PEP) on AM/SSB, and 50W FM, where the original version had 60W AM/SSB and 45W FM. The built in noise reduction function works on both receive and transmit to clean up any static or interference. • Frequency Range: 28.000-29.700MHz (Programmable)• Channel: 40 channels (programmable) in each band• Frequency Band: A/B/C/D/E/F/G/H/I• Frequency Control: Phase-Locked-Loop Synthesizer• Frequency Step: 10Hz, 100Hz, 1kHz, 5kHz, 10kHz, 100kHz, 1MHz• Frequency Tolerance: ± 5.0ppm• Microphone: With push-to-talk/UP/DN and coiled cord• Input Voltage: DC 13.8V normal• Dimensions: L-252 x W-158 x H-48mm• Weight: 1.27kg• Antenna connection: UHF SO239• Temperature Range: 20 to…

2024 saw 46 entrants submit logs in the 41st Practical Wireless 144MHz QRP contest held on Sunday 9th June 2024. The entrants made a total of 1391 valid contacts with stations in 33 different squares (Fig. 1). Entries were down on 2023, possibly due to the weather. 2024 winners The overall winner, leading single operator and leading Welsh station is again the Hereford VHF Contest Group GW1YBB/P operated by Steven Clements G1YBB from Pen-Y-Gadair (800m asl), the second highest peak in the Black Mountains in South Wales IO81KW (Fig. 2). He used a Yaesu FT-817 transceiver and a 9-element DK7ZB antenna. • Runner up and the leading English station is Steve Marsh G4TCU/P operating from IO82WJ. • The leading fixed station is Tony Collett G4NBS operating from JO02AF. • The…

I have been using a single lever Vibroplex paddle since the early 1960s. It has been used with a large variety of keyers, ranging from the early one that I built, the OZ7BO keyer, to some of the latest keyers on the market. All the Vibroplex paddles of the day were constructed in the same way and indeed you can still buy a paddle with same arrangement these days. In fact, a modern Vibroplex paddle looks very similar to my old one, still using springs in fact. The movement could have standard non-jewelled trunion screws and pins and there are also those that have industrial-grade jewels inserted. Other than that, it is essentially the same as the one I had bought for me when I was around 20. The main…

When operating portable, I do enjoy the convenience and simplicity of operating with a random long wire (LW) and ATU. Some would argue this is inefficient, but I use about 12in of coax between rig and ATU, and connect the LW and counterpoise directly to the ATU output, so feedline losses are minimal, and user convenience (and user efficiency) are high! In the past I have built various manual ATU’s for this purpose, including transmatch and L Match versions. I have previously reviewed the Kanga Transmatch, which is excellent but costs nearly £50. A recent L Match I built into my homebrew/P transmitter was built from the junk box, but I reckon if you had to source the polyvaricon, inductor core, wire, switches and knobs, then you would be talking…

As always (well, I did miss one, when I was on the other side of the world!), I made sure I was at the RSGB Convention in October – my ‘must attend’ event of the year. Not that I get to many of the lectures as, for me, it’s an opportunity to catch up with friends and acquaintances, including of course many PW readers and contributors. Once again, the event was at Kents Hill Conference Centre in Milton Keynes although there were some changes to the booking system and the format this year. For example, registration was at the entrance to the Convention area, not in the foyer. Apparently, this was at the venue’s specific request but unfortunately it led to long queues at the registration desk. Something for the…

Steve Rawlings G4ALG kindly wrote, providing a little more information about the CW activities known as ‘Two Metre Tuesdays’. “Two Metre Tuesdays take place from about 18:00 UTC each Tuesday evening around 144.050MHz. Firstly, it’s important to highlight that these weekly events are not contests, but simply an opportunity to have a natter on 2m CW. These activities started in October of last year when fellow UK QRP Group member Chris G3XIZ posted a message on the Group’s email reflector suggesting that members give 2m CW a try. The first Two Metre Tuesday was subsequently arranged for 24 October 2023. Chris G3XIZ had already made a 5-element Yagi, and I soon assembled a 6-element Yagi for use with, at the time, my only 2m rig: an ageing Icom IC-290E. Several people took…