Sommaire pour October 2024 de Practical Wireless

Keith Hamer Keith405625.kh1@gmail.com Garry Smith Garry405625.gs@gmail.com On Coronation Day, 2 June 1953, BBC Television carried, in sound only, Her Majesty’s broadcast to the nation, and beyond, as part of the day’s marathon transmission which finally came to an end with a fireworks display, staged on the South Bank of the Thames. The display began with a 41-gun salute followed by four set-pieces showing portraits, outlined in fire, of HM The Queen, HRH the Duke of Edinburgh, Prince Charles and Princess Anne. Hundreds of Roman candles were lit on two barges moored off the South Bank. The programme ended with the launching of 1,500 rockets. Earlier in the day, as soon as the tail of the Coronation procession had passed Marble Arch, the television unit at Grosvenor Gate was made ready…

Mike Richards G4WNC practicalwireless@warnersgroup.co.uk Andy Talbot G4JNT in a recent RadCom raised an interesting point about using SDR filters with WSJT-X software modes. Using anything other than the standard SSB speech band filter for modes such as FT8 and FT4 is not usually necessary. This is because WSJT-X uses its own narrow-band filtering to isolate the signals for decoding. Therefore, adding additional filtering simply limits the number of signals that will be decoded by excluding those outside the filter passband. Another point to note is that most filters introduce some phase distortion close to the filter skirt that can seriously impair any data channels in the vicinity. This used to be particularly noticeable when RTTY operators tried to filter too close to the desired signal and started encountering errors. Another…

Georg Wiessala wiessala@hotmail.com Irecently took a book down from a shelf I had not visited in some years. A most unusual tome, indeed – I had forgotten that I had it. In Shadows of the State (2018), the author Lewis Bush offers images of (what is left of the) locations of many former Cold War numbers stations, such as the ‘Lincolnshire Poacher’, ‘Cherry Ripe’, and many others. In a way, this is almost an ‘artistic’ kind of book, combining, as it does, accurate aerial photography with (radio) history, geography and the study of clandestine transmitters. Here, ‘mapping’ has come to mean cartographic plotting of many of the formerly covert stations. Unidentified signals and transmitters are still of great interest to many amateur radio operators and short wave enthusiasts today, and…

Steve Telenius-Lowe G4JVG teleniuslowe@gmail.com As a (mainly) HF operator, I have always considered HF DXers and contesters to be the ‘international ambassadors’ of amateur radio, promoting friendships across the world. This was brought home to me recently when I received an email from Yoshihiro Shoji JG7AMD, who I had last met 31 years ago when we were both working in Papua New Guinea. I was licensed as P29DX and Yoshi became P29JA after he took the PNG licensing exams – no mean feat when English is not your mother tongue and you don’t even use the Latin alphabet! (In those days there was no reciprocal licensing agreement between Japan and Papua New Guinea.) In early August Yoshi was on a business trip to the UK and on his way back…

REFURBISHING AN SB200 AMPLIFIER: Martin Evans GW4TPG describes the challenge of refurbishing a classic Heathkit amplifier to make it suitable for use in a modern shack. FACE BEHIND THE CALL: Roger Dowling G3NKH meets Bob McCreadie G0FGX, a presenter of amateur radio’s own popular television show ‘TX Factor’, as it celebrates its tenth birthday. A MAGNETIC LOOP ANTENNA: John Piątkowska-Vooght MW1CFN has a design for a homebrew magnetic loop. A TRIBAND ELEVATED VERTICAL: Billy McFarland GM6DX returns with a design for a simple portable antenna. THE PROTOCOL WARS: Joe Chester M1MWD has a personal take on the ‘wars’ between the various VHF/UHF digital voice modes. There are all your other regular columns too, including HF Highlights, World of VHF, Antennas, Vintage TV & Radio and Data Modes as well as…

Nils Schiffhauer DK8OK dk8ok@gmx.net The third largest magnetic storm since 1985 occurred on 10 May this year. It shook the ionosphere. The global network of magnetometers was the first to feel this shock – the more northerly their position, the sooner, the stronger. Fig. 1 [1] shows the values of seven European stations from north (Reykjavik) to south (Vienna). The German stations Wingst and Niemegk are in fifth and sixth position. What hit the Earth at around 1705UTC had its cause on the sun. Around 60 hours earlier, an explosion occurred above a huge group of sunspots, Fig. 2, which initially generated powerful X-rays, Fig. 3. Within an hour, this flare tore over a billion tonnes of charged matter (plasma) out of the sun by twisting magnetic fields and hurled…

Geoff Theasby G8BMI geofftheasby@gmail.com For many of those who are overcome by ill health in their old age, there are those who can continue their activities with suitable assistance. I speak of the constructors amongst us, who perhaps cannot solder wires together due to tremor of hands or lack of grip. Unlike those who once actively played some physical activity, those pursuing a solitary existence need not give it up. The Radio Amateur Invalid & Bedfast Club caters for those needing aerial erection, equipping a shack or its modification, or the loan of equipment. For more detailed activity, there appears to be little available. I have therefore assembled a number or ‘workarounds’ which should help make life easier. Let me introduce myself. I am Geoff Theasby G8BMI, potentially active on…

Colin Redwood G6MXL practicalwireless@warnersgroup.co.uk Welcome to this month’s What Next. I’m starting by looking at PSK Reporter which works with FT8, RTTY, PSK and other data modes. I’ll then return to the exam theme to look at the various books that are available for those taking the exams after 1 September 2024. What is PSK Reporter? One statement that I’ve often heard from newly licensed amateurs is, “I’m not sure if I am getting out”. Well, if you aren’t making contacts, you need to know if your transmitting system is working. You could measure the power coming from your transmitter when connected via a power meter into a dummy load. Ideally, you’d like to get reports from other stations. But if you aren’t hearing them, what can you do? Another…

21/22 September EAST MIDLANDS HAM & ELECTRONICS RALLY: Beckingham Village Hall, Southfield Lane, Doncaster DN10 4FX. Although the venue has a Doncaster postcode, please note that it is in fact very close to Gainsborough and well connnected to road networks. We invite traders, special interest group exhibitors and visitors with an interest in any aspect of radio - whether amateur, CB, PMR, Meshtastic or in computers and electronics to attend and make this a fantastic weekend! As this will be a 2-day event, we are offering overnight camping on Friday (20th September) and Saturday (21st September), and a Saturday evening barbecue. Refreshments are available on both days. Strictly no dogs (except assistance dogs) allowed at this venue. Doors open for visitors: Saturday 9.30 am until 4 pm, disabled 9.15am;…

News from India Rajesh Vagadia VU2EXP reports, A special workshop on ‘Wireless Technology and its Practical Solutions’ was conducted for Rajkot - Police Wireless Department at Gujarat (India) on 20 July 2024. The venue was the Police Training Center at Rajkot Headquarter. Regional Coordinator of AMSAT-INDIA & The Amateur Radio Society of India, Mr. Rajesh Vagadia VU2EXP gave insight into various Radio Communication protocols, types of modulation, modes & various applications used in Amateur Radio & Police department. As this workshop was targeted for 25 technical wireless officers & radio operators, we focused on the radio communication enhancing methods, utilizing various techniques, using different antennas for specific applications and diagnosis of wireless setup with various measuring instruments incl. SWR/Power Meter, NanoVNA/Antenna Analyzer. We extended a handful of maintenance tips for…

Keith Rawlings G4MIU keith.g4miu@gmail.com Imentioned in last month’s column that MultiPSK now has a new feature that enables it to monitor HF beacons in the NCDXF/IARU International Beacon Project. MultiPSK is a Windows ‘Digi mode’ software package for amateur radio operators and also ‘Utility’ listeners. I’m not sure how long it has been going but it is a long time, and its author Patrick Lindecker F6CTE has been continually updating and improving it over the years. It has benefited from having a good CW decoder for much of its life and in more recent times an NDB decoder was introduced under its CW decoding ‘Button’. Now under the CW mode it has the ability to monitor the NCDXF beacons that are spread throughout the world. The beacons can be used…

Roger J Cooke G3LDI roger@g3ldi.co.uk Prior to me becoming G3LDI, it was usually a home-made transmitter purposely made for NFD by Bill G3CQE, Ted G3IVH or Don G3JIE. That decision had to be made long before the date, of course, to enable construction. It would be a valve device, with relay switching, and muting of the RX. I still have a transmitter built for that purpose by Ted G3IVH. I thought you might be interested in the construction of this transmitter. Ted was very meticulous in his construction techniques. He was an engineer for the electricity board. He built the transmitter with tracking tuning of the PA with the VFO. The pictures, Figs 1, 2 and 3, are self-explanatory but interesting even so. This dates back to the mid 1950s.…

Daimon Tilley G4USI practicalwireless@warnersgroup.co.uk First licensed as a teenager in the early 1980’s, although my first HF rig was a second-hand Kenwood TS-520, I always had a keen interest in QRP. I remember, very well, the Heathkit HW-9 being launched in 1984 and looking at the ads in Practical Wireless with envy. I knew that as a schoolboy, I was not going to be able to afford the HW-9 kit, which was, to me at least, very expensive. I cannot seem to find the purchase price for 1984, but when Ham Radio Today reviewed the rig six years later, in the June 1990 edition (see link below) it was £250 for the basic version and just under £300 if you wanted to add the WARC bands kit – a long…