Innehållsförteckning för October 2025 från Practical Wireless

GRIDS ON THE AIR: The Grids On The Air programme has recently started issuing awards to participants in the challenge. They now have two members who have achieved the milestone of over 750 Maidenhead Locator Grid Squares contacted on HF legacy modes, one of whom is a hairs breadth from the 1000 mark, and 12 who have reached the 500 grid level. Grids On The Air is a scheme for uploading logs of contacts with locator squares or grids, using HF only and ‘legacy’ modes, ie SSB, CW mainly but also allowing AM and FM. The scheme offers award certificates at increments of 250 squares starting at 500. The website is in its early days so far, but in time will support uploading or entering of spots of rarer grid…

In this month’s On a Budget we are going to take a look at the Chinese made Version 2 of a Si4732 Receiver, called the ATS-Mini, Fig. 1. At a cost of £23.49, is it worth the money? Well, first, let us examine what we are buying. The Si 4732 is a ‘Radio on a Chip’ produced by Skyworks. According to the Datasheet, the Si4732-A10 is a “digital CMOS AM/FM/SW/LW/RDS radio receiver IC integrates the complete broadcast tuner and receiver function from antenna input to digital audio output.” Think of it as the very latest, and enhanced version of the venerable old TRF Radio on a Chip, the ZN414, which was featured in my Matchbox Receiver construction article in the February 2024 PW. Features The datasheet lists an impressive array…

Many of us use analysers rather than VSWR meters these days. How did they become so de rigeur? (No pun intended.) The reason, of course is convenience. Using an analyser, I can connect direct to an antenna and instantly read off a complex impedance and a VSWR. Using a VSWR meter I need a radio, and all I can know is the VSWR. But, when I see a number I like, can I simply believe it? I have three antenna analysers here and I’m going to do some comparisons. Analysers on test As Louis (the policeman) says in Casablanca, “Bring in the usual suspects”. See Table 1 and Photo 1. MFJ-269C (now superseded with ‘D’ model) This, or the older MFJ-259B model, is for many amateurs, the ‘hoover’ of analysers.…

practicalwireless@warnersgroup.co.uk Cardboard antennas? Dear Don, The M7GET item in PW August about a DIY microwave aerial was very interesting, as I made a similar one using a 2-element printed circuit type beam from WA5VJB. G3PHO drew my attention to the WA5VJB offering (and others). It is constructed on 1.5 mm polystyrene sheet (Modellers call this ‘Plastikard’. Strips of aluminium selfadhesive tape made the elements according to the published dimensions for such a beam. The matched feed is mounted on a 4mm square section plastic rod sliding in a slightly larger hollow square tube forming the boom. This prevents it turning. To calibrate, tune in a 1296MHz signal, adjust the boom length for maximum signal, then drill the square tube so as to fix its position with a miniature screw, yet…

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At the August Japanese Ham Fair, ICOM unveiled the new IC-7300MK2 HF / 50 /(70) MHz transceiver. Pre-release information & Slideshow video available: Key features: HDMI port for external displays • Built-in CW decoder • USB Type-C with dual virtual COM ports • Enhanced RMDR and Phase Noise performance • Ideal for contesting & DX hunting • 70MHz band is included in the European Version. The original IC-7300 was unveiled in 2015 and is reputed to have sold more than 100,000 units. This success is presumably what is behind Icom prolonging the life of the rig but adding additional features to match or improve on those of Yaesu’s FTdx10. Initial shipments are expected by the end of 2025.  www.icomjapan.com/news/4411…

Rabbit warren anybody? Two DV dongles walk into a bar. Actually, two separate bars on opposite sides of the world. For clarity, a DV dongle is just a device to enable use of digital radio from a PC or other computer. Connecting to the local WiFi in the eponymous bars, they then call up a DMR Talk Group to establish a comms link with each other, using this server somewhere in digital radioland. People then use this comms link to talk to each other. The question is: what callsigns should they use? I have deliberately left out any location data to help you reach the correct conclusion. The answer is of course none! The users may be radio amateurs, the server may have been set up by a radio amateur,…

Looking for something on ML&S’s website recently, I came across Gary Spiers’ video showcasing the G63, a simple 16-channel UHF handheld made by Talinfone in China. In 2022 I bought two of these on eBay, for £58, and somehow I lost them. But while they were with me, I did some testing and started an article, which, I’m glad to report, I’ve found! On discovering that ML&S sell these, I made one of those one femto-second decisions and ordered two more G63s at a cost of £90 plus delivery. Fig. 1 is a photo showing a new ML&S-badged G63 and, inset, one of my originals. That’s a cute radio; even smarter in black. The top surface has a Baofeng-style SMA connector and an on/off/volume knob. The left side has PTT…

The Sun was quiet during July, but that changed in August when there was a whole series of M-class solar flares. Although ten times smaller than the X-class flares reported in the August HF Highlights, even M-class flares can lead to Coronal Mass Ejections and HF blackouts on the daylight side of the world. The August flares started with an M2.9 event on the 3rd which was followed by more most days until at least the 10th. The largest was an M4.4 on 5 August. This activity led to a G2 (moderate) geomagnetic storm on 9 August. According to the SolarHam website, Fig. 1, all this activity emanated from sunspot region AR 4168. SolarHam has been providing realtime space weather data and news for nearly two decades and is…

The first section this month is aimed at the Young Guns, those up-coming radio amateurs who may consider Morse Code an ancient art for ancient amateurs. Nothing is further from the truth so please don’t flip the page to the FT8 section or use your PC or handheld to do what amounts to making a phone call. Where is the sense of achievement in that? Give this section a read and give yourself a challenge. Become a Radio Operator and with an HF transceiver, a simple antenna and a Morse key; talk to the world! Making Morse code irresistible: why young people should embrace the ultimate communication art In an era of smart phones, social media, FT modes and instant everything, suggesting that young people learn Morse code might seem…

Back in the early 1980’s I experimented with 23cm for the first time. I built a DF8QK transverter which came from the VHF Communications magazine. When the transverter was partially completed, I decided to make an antenna to use with it. As commercial 23cm antennas were expensive at the time, I chose to build a small 10-over-10 slot-fed Yagi that I saw in an RSGB Radio Communication Handbook. The antenna was quite easy to build and I used 15mm plumbing pipe for the booms along with 2mm brass rods for the elements. When it was finished, I mounted it on the top of my antenna stack on the chimney. The partially completed transverter gave an output of around 100mW and with my new 10-over-10 Yagi I was able to work…

Last month, I opened the column by speculating that it had been a poorer than normal Es season and perhaps there was some connection with the peak of the solar cycle. Within 24 hours of writing those words, there had been a 2m opening from the UK to Israel! Around 1200UTC on 13 July, 4X5CD (KM72) was worked by at least a couple of stations, John G4SWX (Suffolk) being one of them. What was interesting to me, at least, that this wasn’t purely an east coast thing. Israel has been worked before on 2m from the east coast, but 4X5CD was heard further across the country, including in IO80 by Paul Pasquet G4RRA (Okehampton), which as far as I know is more unusual. Down in Cornwall, Dave Edwards G7RAU (The…

I’ve always enjoyed building my radio kit, as that’s how I started in amateur radio as a boy; it was all we could afford! However, advances in modern technology, such as miniature surfacemount components and multilayer PCBs, have made home construction of high-performing equipment increasingly difficult. One area of our hobby that has always managed to find a way is the world of QRP. This is thanks to many ingenious designers who devote many hours to creating clever designs that they then share with the rest of us. One such prolific designer is Hans Summers G0UPL/AB7BF, of QRP-Labs. One of the best current examples of his work is the QMX+ transceiver, Fig. 1. I’ve been looking for a new QRP rig that I could use in remote locations, and the…

BBC Broadcasting House, London: Part II By early 1931, the construction of Broadcasting House was progressing well, especially the areas below street-level, and the BBC were confident that the premises could be occupied by the autumn of that year. Broadcasting House was built on the former site of Foley House which had been demolished some years earlier. There were some initial building difficulties. The foundations presented various interesting problems. An old brick conduit, which carried a stream from Hampstead, traversed practically the whole length of the site. The problem was not only to cover this with a casing of concrete sufficiently strong enough to resist the weight of the building, but also in laying bare the conduit during the excavation to avoid the possibility of it bursting under the inward…

HAYTOR VALE REPEATER GROUP INSTALLS GB7HV - FM ANALOGUE AND C4FM REPEATER: The newly-formed Haytor Vale Repeater Group (HVRG) is proud to announce the installation of a new VHF repeater at Haytor Vale, in close proximity to the famous Haytor rock on Dartmoor, Devon. The repeater, callsign GB7HV, is situated just south of the famous granite outcrop and tourist site Haytor, which was formed over 280 million years ago! The group was granted permission to set up the repeater in May 2025. Key members of the team completed the installation on 9 August and GB7HV commenced broadcasts later that day. GB7HV is now fully operational with coverage tests showing excellent results, especially across the south coast of Devon and Dorset and onwards towards Bournemouth. Wires-X connectivity will follow in due…