Indholdsfortegnelse for August 2022 i Radio User

The Perseus22 is a 4-channel, direct sampling receiver with continuous frequency coverage from 10kHz to 225MHz and a typical image rejection larger than 70 dB. All channels are sampled synchronously, by a high-SNR, 14 bits A/D converter, and a software-defined digital down converter processes them. This is implemented on an FPGA, the outputs of which are routed to the host PC by a USB 3.0 controller, allowing wide-bandwidth IF applications. Frequency coverage is split into 2 groups of channels (two for the VLF-HF frequency range, the others for VHF), each one capable of ‘diversity’ reception. This can, it is claimed, reduce noise in the order of tens of dB. All channels include an analogue RF front end, equipped with attenuators, preselection filters, and amplifiers. The receiver enclosure is machined from…

martin_butera@yahoo.com.ar The first digital radio transmission in Brazil was made in 2020, on 11910kHz (in DRM). After more than two decades of controversies surrounding the format, it seemed that digital radio in Brazil was finally taking off. The historic initial transmission was captured successfully in various parts of Brazil, French Guiana, the United States, Canada, New Zealand, Japan, and other countries. However, subsequent DRM broadcasts turned out to be relatively short-lived, and they mysteriously disappeared from the air, with no further news. I will try to unravel the mystery of what happened, through an interview with Francisco Braccini, one of the main enthusiasts of digital radio in Brazil (Figs. 1 and 2). Francisco has a military background and a degree in Communications from the Agulhas Negras Military Academy. He has…

wiessala@hotmail.co.uk In the world of aircraft tracking, things have moved on from the ‘dongles’ and ‘pucks’ that many of us used to operate in the shack in years past. Therefore, when John Power at ML&S offered me a review unit of the jetvision Air!Squitter (Figs. 1 and 2), I flew at the chance because I wanted to see just what is possible these days, especially in terms of the range of reception of ADS-B signals. Out of the Box jetvision is a brand of Günter Köllner Embedded Development GmbH (N.B.: ‘GmbH’ is ‘Gesellschaft mit beschränkter Haftung’ in German; a limited company). The jetvision Air!Squitter is sold here in the UK by ML&S Martin Lynch & Sons Ltd. The device aims squarely at those aircraft monitoring hobbyists who would like to…

gi7ivx@btinternet.com This month, I will be looking at Digital Selective Calling (DSC) and at numbers – no, I am not going to give you a maths lesson but an insight into the various numbers associated with shipping that may be confusing for some readers, especially the novice starting to listen to maritime communications. It has been several years since I last looked at DSC, and I am only too aware of many newcomers to the hobby who might be unsure regarding the various maritime communication modes. DSC Distress and urgent transmissions are available on the following MF, HF and VHF marine frequencies: 2187.5, 4207.5, 6312, 8414.5, 12577, 16804.5kHz, and 156.525MHz (CH70). These are the most common DSC frequencies monitored. However, there are many other MF/HF frequencies allocated for DSC use.…

Scottandrew.caldwell@yahoo.co.uk The famous Hall Street Marconi factory in Chelmsford started life as a silk mill, built by John Hall of Coggeshall in 1856. The site was subsequently purchased by the Courtaulds of Braintree in 1865. Even later, it was acquired by Guglielmo Marconi (1874-1937; Fig. 1) in 1898. A plaque on the east wall commemorates the site’s past life as Marconi’s first wireless factory. But why did Marconi select Chelmsford? London was the commercial capital of the Empire at the time and was initially considered the prime location for Marconi to site his first wireless factory. However, London had many disadvantages when compared to Chelmsford. The most prominent of those concerned the high levels of electrical noise that originated from tramways and lifts. Chelmsford was also still relatively underdeveloped, in…

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50 million adults in the UK continue to listen to the radio (Q1 2022, RAJAR). McIntosh has worked diligently to get the best from the much-loved medium with the new MR89 AM/FM Tuner (£6,800). McIntosh’s high-end audio engineers have recently turned their attention to maximising sound quality from AM/FM broadcasts, culminating in the launch of the new MR89 AM/FM Tuner. A thoroughly updated stereo receiver for the modern music lover, the new MR89 benefits from a plethora of advancements including adjustments to the sensitivity, signal-to-noise ratio, harmonic distortion, channel selectivity and stereo separation. The MR89 also features exclusive McIntosh radio frequency (RF) circuitry that can receive both strong FM signals from nearby stations (avoiding the overload and distortion that can plague everyday receivers), while also being able to tune in…

dj.daviator@btinternet.com The Royal Jubilee Flypast on 2 June 2022 (Fig. 1) involved over 70 individual aircraft and was a marvel of precision timing and superb planning. The faster participants gathered over the North Sea to enter holding patterns and eventually formed into line astern under the direction of RAF controllers of 78 Squadron, based at the London Area Control Centre at Swanwick. The overflight of Buckingham Palace was made at between 1,000 and 1,400ft. As soon as the flypast ended, the controllers were able to restart normal operations. In the meantime, London Heathrow and City Airports had suspended operations, with inbound traffic in holding patterns to the southeast and northwest. The playback facility on Flightradar24 shows just how efficiently the aircraft were peeled off the stacks in the most efficient…

RADIO USER AT THE 29TH BRAZILIAN BROADCASTING CONGRESS: Our South American roving columnist, Martín Butera, was recently accredited to participate in the 29th Brazilian Broadcasting Congress, whose central theme will be Radio and TV: For Everyone, Everywhere. The meeting will take place on November 16th and 17th 2022. The event will also pay tribute to 100 years of radio in Brazil and 60 years of ABERT (Associação Brasileira de Emissoras de Rádio e Televisão). The meeting will be an opportunity to discuss relevant issues for broadcasting in the context of technological convergence in Brazil and the rest of the world. This congress is considered the largest radio and TV event in Brazil and South America and will be attended by renowned national and international personalities, as well as political and…

SDRplay: What’s New Those familiar with the SDRplay series of receivers will have, no doubt, used the SDRUno software. The software is very nice to use, but the big snag is that it only runs on Windows machines. Earlier in the year, SDRplay announced SDRConnect. What’s SDRConnect? Well, in short, it’s a cross-platform piece of software to work in conjunction with the SDRplay receivers. Demonstrations have been seen at the Dayton Hamvention and also Friedrichshafen, where the software was seen running on a Mac (OS X) and a Raspberry Pi. There will also be the option to situate the receiver remote from the computer running the SDRConnect software. This sounds very exciting. The bad news is that the software is still in development and a few months away from being…

Icom’s SHF-P1 concept model and the IC-PW2 HF/50 MHz 1kW linear amplifier were shown at the recent Dayton Hamvention, one of the world’s largest amateur radio events held between May 20th-22nd 2022. The event, which saw it celebrating its 70th anniversary had the Icom team out in force with new products including the forthcoming IC-T10 dual-band hand-portable and glimpses into these future products. The ICOM stand was bustling with many amateur radio operators asking questions about the SHF-P1 concept project model, part of the development project called the ICOM SHF Project (Super High-Frequency Band Challenge) aimed at developing a new amateur radio for use in the 2.4GHz and 5.6GHz bands. Visitors were also excited to be getting a good look at the forthcoming IC-PW2. To find out more about these…

wiessala@hotmail.co.uk The Tecsun PL-368 is the successor model to the Tecsun PL360/CountyComm GP-5 DSP and Tecsun PL365/CountyComm GP-5 SSB radios. It weighs less than those. The PL-368 receiver comes in a small box with a range of useful accessories, such as a carrying pouch, earphones, the rotatable set-top AM aerial, and a USB charging cable (Fig. 1). The unit under review carried serial number PL368BNV2204036. There are 28 (small-ish) pushbuttons at the front of the PL-368, for frequency entry, mode-control and some other essential functions. About half the casing is taken by the loudspeaker. The charge (5V) port, tuning wheel and volume control are on the left-hand side of the unit. They are also used for bandwidth and time adjustments. There is a (not-too-sturdy) belt clip at the back, and…

July 30th (Saturday) BATTLE PROMS: Highclere Castle, Newbury RG20 9RN. Another two-hour orchestral programme in a stately home setting, with appearances by the Red Devils Parachute Display Team, plus a Spitfire. July 30th and 31st (Saturday and Sunday) OLD BUCKENHAM AIR SHOW: Old Buckenham, Norfolk NR17 1PU. An excellent mix of ‘warbirds’ and civilian aircraft, classic and military vehicles, plus many ground-based events. www.oldbuckenhamairshow.com July 30th to August 6th (Saturday to Saturday) SWANAGE CARNIVAL: Swanage Bay, Dorset BH19 1LD. A week of family activities, which usually includes some air displays. www.swanagecarnival.com August 1st (Monday) DUXFORD FLYING DAY - ‘YOUNG AVIATORS’: Duxford, Cambs CB22 4QR. A themed show aimed at fostering children’s interest in aviation. https://tinyurl.com/5cv4bkxh August 5th to 14th (Friday to Sunday) FALMOUTH WEEK: Falmouth Seafront TR11 3DF.August. Mostly sailing…

artwork@silverbirch.me.uk In January 2021, the Radio Enthusiast website published an article on amateur radio astronomy and the United Kingdom Radio Astronomy Association (UKRAA). https://tinyurl.com/2vyf8svj My interest is in astronomy, and – as this is a radio magazine – my focus will be on using radio and electronic instruments to record the natural world. There are a surprising number of ways that enthusiasts can make a real contribution to science, and these can be an interesting addition to our hobby. In my view citizen science projects seem to fall into three broad categories: Examining and classifying. This is exemplified by the withChrisLintott as Principal Investigator. Recording and observing. Here the data is gathered by the participants for analysis by scientists. The best-known example in the UK is probably the Working as…