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Becoming an Amateur Radio Operator with Dr David Maddison, VK3DSM Becoming a radio amateur, or “ham” as they are known, can be a rewarding hobby and is perfect for those who are already interested in electronics. D ue to my interest in electronics and communications, I have always wanted to become a radio amateur. I was first introduced to it in high school but never got around to it for various reasons. I finally decided to get my licence. This article describes that process and the sorts of equipment and activities associated with being a ham. This article is written from the point of view of a novice. There are many hams out there with decades of experience, but I wanted to document the process as someone who is entirely new to the hobby. This is a brief introduction to a hobby that is huge in scope. There are thousands, if not millions, of websites and links relating to amateur radio (Google lists 71,700,000 results for “amateur radio” without quotes). Here, we can only cover a tiny selection of possible topics. What is a radio ham? A radio ham is a licensed operator who uses approved portions of the radio spectrum for the following purposes, both recreationally and socially: 22 Silicon Chip • non-commercial radio transmission and reception • technical investigations and experiments with radio • self-education in the field of aspects of radio reception and transmission • communication with other radio hams For younger people, it can also open doors to a career in electronics and communications. It is certainly not to become a radio DJ or for entertaining others (someone asked me about that). A typical radio ham has equipment in a part of the house designated “the shack” (not necessarily a physical shack, but it can be!) including, at minimum, a transceiver, a standing wave ratio (SWR) meter for measuring antenna efficiency and an antenna tuner. Outside the house, there may be one or more antennas that can be connected to the transceiver. A ham may also be “mobile” and have similar equipment in a car or RV, or simply carry it to various locations in a backpack. Activities will be discussed later, but generally include making contact Australia's electronics magazine with other hams, either locally or across the world, using a variety of analog and digital modes. Apart from recreational use, for independent-minded people, there is the satisfaction of having a communication method that will work without other infrastructure. The recent Optus outage that left many Australians without communications is a reminder of the vulnerability of our communications infrastructure. What has changed over time? One of the biggest differences between the ‘old days’ of ham radio and the present is the extensive use of digital technology now, which has given the hobby a whole new lease of life and many new possibilities. One of the past attractions of becoming a radio amateur was free communication with friends and relatives around the world. Long-distance telephone calls were extremely expensive. That is no longer the case. Also, hams used to make most of their own equipment. Today, most equipment is commercially available. Even so, many prefer to make as much siliconchip.com.au Table 1 – radio frequency bands per the ITU (International Telecommunication Union) Frequency name Abbr. Freq. range Wavelength Some common uses Extremely low frequency ELF 3Hz-30Hz 100,000km10,000km Submarine communications Super low frequency SLF 30Hz300Hz 10,000km1,000km Submarine communications Ultra low frequency ULF 300Hz3kHz 1,000km100km Submarine communications, mine and cave communications Very low frequency VLF 3kHz-30kHz 100km-10km Submarine communications, radio navigation systems, time signals, geophysics Low frequency LF 30kHz300kHz 10km-1km Radio navigation, time signals, longwave AM commercial broadcasting in Europe and Asia, RFID, amateur radio (certain countries) Medium frequency MF 300kHz3MHz 1,000m-100m AM commercial broadcasting, amateur radio, avalanche beacons High frequency HF 3MHz30MHz 100m-10m Shortwave & amateur radio, 27MHz CB, long-range aviation & marine communications, radio fax, over-the-horizon radio Very high frequency VHF 30MHz300MHz 10m-1m Aircraft communications, amateur radio, emergency services, commercial FM broadcasts Ultra high frequency UHF 300MHz3GHz 1m-10cm TV broadcasts, microwave ovens, radars, mobile phones, GPS, wireless LAN, Bluetooth, ZigBee, satellites, Australian UHF CB Super high frequency SHF 3GHz30GHz 10cm-1cm Wireless LAN, radar, satellites, amateur radio Extremely high frequency EHF 30GHz300GHz 1cm-1mm Satellites, microwave links, remote sensing, amateur radio Tremendously high frequency THF 300GHz3THz 1mm-0.1mm Remote sensing, experimental uses siliconchip.com.au (continuous wave; for Morse code), beacon modes, narrow band, wide band, repeater inputs & outputs, amateur TV (slow scan TV), satellite etc. For further details and specific usage of the Australian amateur radio band plans, see the document from the WIA (Wireless Institute of Australia) at: siliconchip.au/link/absn Table 2: amateur bands and the radio spectrum 10m (28.0-29.7MHz) 2m (144-147MHz) 70cm (430-450MHz) 20m (14.00-14.35MHz) 6m (52-54MHz) 23cm (1240-1400MHz) 13cm (2400-2450MHz) 6cm (5650-5850MHz) As well as power limits, bandwidth limitations apply. EIRP is effective isotropic radiated power. Higher licence levels can also use bands for lower levels. 630m (472-479kHz), 5W EIRP 160m (1.800-1.875MHz) 30m (10.10-10.15MHz) 17m (18.068-18.168MHz) 12m (24.89-24.99MHz) 3cm (10.0-10.5GHz) 1.25cm (24.00-24.25GHz) 7.5mm (47.0-47.2GHz) 120W to 400W 15m (21.00-21.45MHz) ADVANCED 40m (7.0-7.3MHz) 2200m (135.7-137.8kHz), 1W EIRP 10W maximum 80m (3.5-3.7MHz) 30W to 100W Australia has three licence levels: Foundation, Standard and Advanced. You can sit for any of these for your first licence; Standard and Advanced require greater knowledge. You can migrate to a higher licence level by taking another exam. As the licence level increases, more bands and higher power output levels become available. The Foundation Licence is a popular starting point. There is no minimum age to obtain a licence in Australia. Additional types of licences include those to operate a repeater or beacon station for the benefit of other amateurs. A list of what bands you can operate is shown in Table 2, while Table 1 shows the frequencies, wavelengths and uses of the main ITU (International Telecommunication Union) radio bands (for all purposes). Amateur radio signals can operate in all the bands shown in that table from LF onward (even including the THF band). Note that the term “band” has FOUNDATION Licensing different meanings in different contexts. For example, the ITU bands describe frequency decades, while amateur bands, such as 10m, 20m, 40m etc are much narrower. Each amateur band is further divided into segments for voice or digital, various analog modes such as AM, FM, SSB (single-sideband), CW STANDARD as possible, but you can just buy it if you can’t or don’t want to make it. 3.7mm (76GHz-81GHz) 2.5mm (122.25-123.00GHz) 2mm (134-141GHz) 1.25mm (241-250GHz) April 2024  23 VK prefixes Fig.1: the 40m amateur band is accessible to Foundation Licence members. Original source: www.wia.org.au/members/bandplans/data/documents/ Australian%20Band%20Plans%20200901.pdf An example of band usage from that document is shown in Fig.1 for the 40m amateur allocation. For that band, amateurs have exclusive use of the first 100kHz (primary users) but have to share with other users on the upper 200kHz (secondary users). Listening in We will discuss options for transceivers shortly, but even if you are not a licensed ham, you can still listen in on the bands. There are a few ways to do that. You can listen using free online software-­ defined radios (SDRs) that can be found at websites like http:// kiwisdr.com/public/ and http:// websdr.org/ They are located all around Australia and the world. These are also useful for when you become a ham and want to check how your signal is getting out. A particularly good one is the Ironstone Range SDR in South Australia at http://sdr.ironstonerange. com:8075 You can buy an SDR receiver from Australian company WiNRADiO Communications (https://winradio.com). It connects to a PC to operate. One model that covers 9kHz to 49.995MHz is the WR-G31DDC “EXCALIBUR”; see https://winradio. com/home/g31ddc.htm and our review in the June 2012 issue (siliconchip.au/ Article/636). 24 Silicon Chip Inexpensive SDR ‘dongle’ receivers based on the RTL2832U chip are available that work with open-source software, but for lower frequencies, you may also need an upconverter, such as the SiDRADIO (October & November 2013; siliconchip.au/Series/130). Also see these websites: • www.rtl-sdr.com • www.nooelec.com/store/sdr.html • https://gqrx.dk/ • www.gnuradio.org Another way to receive ham and other bands is a shortwave receiver. One highly regarded example is the Tecsun S2000, which we reviewed in the August 2016 issue (siliconchip. au/Article/10047). It is still a current model; refer to siliconchip.au/link/ abte How many ‘hams’ are there? In Australia, at the time of writing, there are 15,499 radio hams (see www. wiaawards.com/charts/amateurs. php). Many other interesting Australian statistics can be found at www. wiaawards.com/charts/index.php As of March 2023, there were 6730 hams in New Zealand (as per the PDF at siliconchip.au/link/abso). There were about 780,000 in the USA as of 2021 (siliconchip.au/link/ absp). It is said that there were about 3 million hams worldwide back in 2000, but there has been a decline in numbers. At present, we estimate there are Australia's electronics magazine Australian hams are allocated a unique callsign with a prefix based on their state or territory of residence as follows: VK0   Australian Antarctic Territory, Heard Island, Macquarie Island VK1   ACT VK2   NSW VK3   Victoria VK4   Queensland VK5   South Australia VK6   Western Australia VK7   Tasmania VK8   Northern Territory VK9C   Cocos-Keeling Islands VK9L   Lord Howe Island VK9M   Mellish Reef VK9N   Norfolk Island VK9W   Willis Island VK9X   Christmas Island around 1.75 million currently active. Earning a Foundation Licence The Foundation Licence demonstrates that you have enough knowledge and skills to assemble a basic amateur station from commercial equipment and supplies, and operate it according to the correct procedures and without causing inappropriate interference to other radio spectrum users. You would typically attend a training course with a local amateur radio club (or by yourself). However, before that, you should purchase and study the WIA publication “The Foundation Licence Manual – Your Entry Into Amateur Radio, 4th Edition”, available from equipment suppliers and radio clubs. The exam is based on that book. It currently costs $35 plus $15 postage – see www.wia.org.au/licenses/ foundation/foundationmanual Another supplementary book from the WIA is Peter Parker’s “Australian Ham Radio Handbook”, available from his website (https://books.vk3ye.com). The hard copy costs $24.95. Finding a club To find your local club in Australia, visit www.wia.org.au/clubs/ and access the pull-down menu that says “Affiliated Radio Clubs” or search Google. siliconchip.com.au New Zealand clubs can be found at www.nzart.org.nz/contact/branches/ list and information about becoming a radio amateur in NZ is at www.nzart. org.nz/learn I contacted two nearby clubs in the Melbourne area, the Moorabbin & District Radio Club Inc. (https://mdrc. org.au) and the Eastern & Mountain District Radio Club (EMDRC; www. emdrc.com.au). I took my course and exam with the one that first offered it at a convenient time. It is OK to join two or more radio clubs; many do, as different clubs cater to various interests. You will find ham radio clubs to be very friendly, helpful and welcoming of new members. Some radio clubs offer free licence training when you first join the club. Some clubs also provide members with discounts at stores like Jaycar and Altronics. The exam There is a set course curriculum for all licence levels. For the Foundation Licence, the WIA website says, “… you will learn the how Amateur Radio relates to other users of the radio spectrum, licence conditions, technical basics of electricity and electronics, transmitters, receivers, feedlines and antennas, propagation, electromagnetic compatibility (EMC), and electromagnetic radiation (EMR).” Since 2004, knowing Morse Code has not been required, although many people still enjoy using it. Randomly generated Foundation Licence practice exams can be found on the WIA website at www.wia.org. au/licenses/foundation/onlineexams/ foundation.php You can repeat these practice exams as often as you want to. Once you have studied and perhaps taken a course with a radio club, you arrange with the club to sit the exam. The Foundation Licence has a written exam with 25 questions with a passing grade of 70% that you have half an hour to complete. There is also a practical component to the exam, involving some oral questions and a demonstration of practical knowledge in connecting up a basic amateur station and putting it on the air. The results are sent to the Australian Communications and Media Authority (www.acma.gov.au/amateur-radio), who issue you a licence if you get a passing grade. As for the cost, the radio club may still charge for coursework and ACMA charges for certain services, such as an exam fee and callsign assignment. However, there is no longer an annual fee for the licence, similar to the USA, Canada, New Zealand and the UK. Before taking the exam, you might also want to watch some YouTube videos by Ron Bertrand on the Foundation Licence course. Some are slightly outdated compared to the current syllabus, but the differences are not significant, see siliconchip.au/link/abtc We haven’t tried it, but it is possible to sit Australian or American amateur exams online via Volunteer Examiners of Australia (https://vea.org.au). Now that you have a licence The first thing to do is set up your station. At the minimum, it should have a transceiver, an antenna tuner, an SWR meter and an antenna. Many modern transceivers incorporate an SWR meter and an antenna tuner, so separate devices may be unnecessary. Ideally, you will also have an internet-­ connected smartphone or computer nearby to look up call signs or other information. You can then call other hams. There is a procedure to call other amateurs, which you will learn during your course. After checking that a frequency is not in use, you might broadcast: CQ CQ CQ this is VK1ABC VK1ABC VK1ABC, over The response might be: VK1ABC, this is VK2XYZ, over. See the WIA manual for further examples. Note that you can look up the call signs of other hams on the website www.qrz.com and maintain a page with information about yourself and your equipment. They also have discussion forums. When using voice mode to contact others, the conversation should be polite with no expletives. Topics can include technical aspects of your station, such as your rig or antenna, ham radio in general, or even topics not related to radio. You may relay personal messages, but encryption or secret codes are not permitted, and neither is station operation for commercial or entertainment purposes. Controversial or divisive topics are not in the spirit of amateur radio. Some people choose not to converse, as they are just interested in making contacts or using digital modes. Quite a few special ‘Q-codes’ are used to shorten common terms and situations (especially when using Morse code). Until you are familiar with them all, keeping the list on hand during radio conversations would be a good idea. Some examples are shown in Table 3. The NATO phonetic alphabet is used for spelling things out, as shown in Table 4. Long-distance transmission via the ionosphere The ionosphere is fundamental to Table 3 – common Q-codes Table 4 – the NATO phonetic alphabet using ICAO spelling Q-Code Meaning A: Alfa B: Bravo C: Charlie D: Delta E: Echo F: Foxtrot G: Golf H: Hotel I: India J: Juliett K: Kilo L: Lima M: Mike N: November O: Oscar QRZ who is calling me? P: Papa Q: Quebec R: Romeo S: Sierra T: Tango QSB fading signal U: Uniform V: Victor W: Whiskey X: Xray Y: Yankee QSL acknowledge receipt Z: Zulu 1: Wun 2: Too 3: Tree 4: Fow-er 5: Fife 6: Six 7: Sev-en 8: Ait 9: Nin-er QRM man-made interference QRN static crashes QRP low transmitting power QSO a conversation QSY change frequency QTH location siliconchip.com.au 0: Ze-ro Australia's electronics magazine April 2024  25 Table 5 – typical amateur radio transmission distances Fig.3: types of HF radio propagation, including line of sight (LOS), ground wave, skywave and NVIS (near vertical incidence skywave). Original Source: www.qsl.net/4x4xm/HF-Propagation.htm long-distance (DX) HF amateur radio operation. This layer in the atmosphere, from around 48km to 965km, contains layers of ionised gases (with the outer electrons removed by sunlight). That renders them electrically conductive and thus capable of reflecting HF radio waves. The layers in the ionosphere change from night to day, as shown in Fig.2. Fig.3 shows the several propagation modes of radio waves. LOS (line of sight) transmission is when stations are visible to each other. UHF CB (477MHz) or FM commercial broadcasting (88-108MHz) are common examples of such a propagation mode. Ground wave propagation occurs at frequencies below about 2MHz during daytime. Radio waves follow parallel to the Earth’s surface and are interrupted by mountains etc. AM Broadcast stations are an example of such propagation. Skywave propagation is where radio waves are reflected off the ionosphere. NVIS (near vertical incidence skywaves) is a special form of skywave propagation suitable for transmission over limited distances and from areas such as valleys. It is often used by military or emergency services. Skywave propagation is the main mode for radio waves from about 3MHz to 30MHz (commonly called shortwave). The ionosphere also refracts frequencies from ELF (3-30Hz) to LF (30-300kHz). MF waves (3003000kHz) propagate by ground waves by day or ground waves and ionospheric E and F layer refraction at night (which is why AM radio stations travel further at night). VHF signals (30-300MHz) occasionally propagate via ionospheric refraction, tropospheric ducting (through a layer of air of different refractive index caused by a temperature inversion which bends the signal back to Earth) or meteor scatter (off ionised meteor trails) but are usually line-ofsight, passing through the ionosphere and into space. The ionosphere is imperfect; parts of it can ‘come and go’, and the layers can move up and down somewhat, which is why radio signals can fade and return. One such layer is called “sporadic E” – see Fig.4. There is a critical frequency at which a signal is either refracted by the ionosphere and returns to Earth or passes through the ionosphere Australia's electronics magazine siliconchip.com.au Frequency Band Range 3.5-3.7MHz 80m Up to 150km during the day and 3000km at night. 7.0-7.3MHz 40m Up to 1000km during the day; worldwide during good conditions at night. 14.00-14.35MHz 20m Reliable worldwide contacts, day and night, during sunspot maxima or in the daytime during sunspot minima (requires a Standard or Advanced Licence). 21.00-21.45MHz 15m Worldwide, mostly during the daytime. 28.0-29.7MHz 10m Worldwide during high sunspot activity and up to 3000km in summer. This is the widest HF band and close to the familiar 11m/27MHz unlicensed CB band, with similar propagation characteristics. 52-54MHz 6m This VHF band has propagation characteristics between HF and VHF. During high sunspot activity, worldwide propagation is possible (requires a Standard or Advanced Licence). 144MHz 2m Local coverage (more via tropospheric ducting); worldwide via repeaters. 430-450MHz 70cm Local coverage (more via tropospheric ducting); worldwide via repeaters. Fig.2: the ionosphere’s radio-reflective layers and sub-layers change between night and day. Source: https://w.wiki/93Xz 26 Silicon Chip and goes into space. This frequency depends on the amount of ionisation in the atmosphere (electron density) and the radio wave’s incidence angle. With the right frequency and ionospheric conditions, even with the 10W or less permitted to a Foundation Licence operator, an amateur radio signal can propagate anywhere in the world. A beginner with a primitive hookup wire antenna around 10m long, raised a few meters or more off the ground (higher is better), and an antenna tuner, should have few problems getting 1000km contacts on the 40m/7MHz band. Far better antennas are easily possible and inexpensive; we will discuss them later. Of course, achieving long ranges is not the only criterion by which success in the hobby should be judged. Some operators are perfectly content with local contacts. Repeaters VHF and UHF signals, such as on the 2m and 70cm bands, propagate mainly via line of sight. A network of repeaters, maintained by volunteer hams, has been established to increase their range. They are primarily located on buildings, towers and mountains; they receive and re-transmit signals to dramatically increase the available range. Digital modes such as C4FM, D-Star (www.dstar.org.au), DMR (https:// vkdmr.com) and P25 are supported by various repeaters. Worldwide contacts are possible with some modes; some repeaters are connected via the internet. Repeaters have different ‘input’ and ‘output’ frequencies, as shown in Fig.5; this mode is called duplex, as opposed to station-to-station communication, which is called simplex (the same frequency for reception and transmission). Maps of Australian repeaters can be found at: www. onlinerepeatermap.com EchoLink (www.echolink.org) and IRLP (www.irlp.net) use software to connect individual amateur stations or repeaters over the internet. Typical transmission distances that can be achieved are shown in Table 5. Fig.4: the ionospheric layers during the day and night, including the sporadic E layer and electron density (ionisation level). Original source: www.sws.bom. gov.au/Educational/5/2/2 Sunspots Sunspots are temporary regions of lower temperature on the sun caused by intense magnetic fields. Sunspots come and go according to an 11-year siliconchip.com.au Fig.5: how a repeater works (top, duplex) compared to station-to-station transmission or “talk around”, in which the repeater is bypassed (bottom, simplex). Original source: https://w.wiki/93X$ Australia's electronics magazine April 2024  27 solar cycle (see Fig.6). The sun is more active when there are more sunspots, which causes more ionisation of the ionosphere, a favourable condition for long-distance radio propagation. We are currently approaching the peak of the present solar cycle, making it an excellent time to become a ham – see Fig.7! Building your own equipment Fig.6: historic sunspot activity showing the approximately 11-year cycle. Source: https://w.wiki/93Y2 (GNU FDL). Fig.7: the present Solar Cycle 25 measurements and predictions show favourable radio conditions for the next few years. Source: www.weather.gov/ news/102523-solar-cycle-25-update Fig.8 (above): Icom’s IC-705 portable transceiver. An optional backpack is available for transport. Fig.9 (left): the (tr)uSDX pocket transceiver. 28 Silicon Chip Australia's electronics magazine Because modern commercial SDRs (software-defined radios) are so good, it is tough to build a competitive transceiver, although some people do. Of course, it is still possible to make traditional analog transceivers, but these days, hams are more likely to focus on building antennas; there are lots of online instructions for doing so. If you want to build your own transceiver, Paul VK3HN has made several videos about ‘scratch-building’ various transceivers and other items. See his YouTube channel at siliconchip. au/link/abtf and also https://vk3hn. wordpress.com LimeSDR (siliconchip.au/link/absq) has applications in ham radio; for more on that, see siliconchip.au/link/absr Peter Parker VK3YE has also produced many books and videos about building your own equipment – see https://books.vk3ye.com Choosing a transceiver You could start with a second-hand rig from a hamfest, but there are risks with any second-hand goods. Inexpensive rigs are available that are made in China, some of which are frowned upon by some hams. Then there are the traditional quality brands commonly available in Australia, like Icom and Yaesu. Since I like travel and bushwalking, I wanted a portable rig. I also wanted a durable, high-quality rig that I could use at home as a base station, one that I could grow with that was supported with accessories and worked on HF, VHF, UHF etc. I also wanted a “waterfall display”, which shows which frequencies have activity. I chose the Icom IC-705 (Fig.8), as it had all the features I wanted; it is a veritable “shack in a box”. The IC-705 is highly regarded worldwide and does everything you need as a beginner ham, both for base station and mobile use. For example, it has full coverage for receiving and transmitting on all amateur bands in the siliconchip.com.au What happened to shortwave radio? Fig.10: the Quansheng UV-K5(8); you also need the programming cable. HF, VHF and UHF frequencies from 160m to 70cm (every band most amateurs are likely to use). The advantage of an all-mode, wide-coverage transceiver is that it theoretically avoids the necessity of buying more equipment later (but good luck with that!). Its power output is limited to 10W on external power or 5W on battery. 10W is the maximum power for a Foundation Licence; you could pair it with a compatible linear amplifier or buy a base station for more advanced licence classes. Do not use a linear amp with the optional AH-705 antenna tuner, as it won’t handle the power. The IC-705 costs a little under $2000 from Australian retailers, while the strongly recommended matching AH-705 antenna tuner is around $550. If you want only a base station, another possible model is the Icom IC-7300, for around $1600. It has a built-in antenna tuner and can deliver 100W, so it would be a better deal if you don’t need portability. The IC-705 is very similar to the IC-7300 but with fewer features. However, the IC-7300 does not have 2m and UHF coverage like the IC-705. Both rigs require a 13.8V power supply, which can be generic. The IC-705 requires 3A on external power, while the IC-7300 requires 21A at maximum output. Many radio amateurs got their start by listening to shortwave radio broadcasts at a young age. Many of these broadcasts came from national governments such as Australia (Radio Australia), the UK (BBC) and the USA (Voice of America). When the Cold War ended, the stations were either shut down (as in the case of Australia) or their services dramatically reduced. The abandoned frequencies were mostly taken over by the government of China, which now has hundreds of stations. China took over Australia’s radio slots for the Pacific Islands; however, Radio New Zealand Pacific maintains a presence (see www. rnz.co.nz/international). Australian radio amateur Dave Stuart VK3ASE took over two of Radio Australia’s frequencies, 2310kHz and 4835kHz. He broadcasts his own musical program from central Victoria at about 100W as a commercial licensee. The station is non-profit and is called Shortwave Australia. See the videos titled “Tuning in to Shortwave Australia” at https://youtu. be/qrfvcJHti0M (Peter Parker) and “Shortwave Aust Latest Developments” at https://youtu.be/V-0uag9qdhs Icom IC-7300, with HF and 6m but not 2m or UHF. Much smaller HF transceivers are possible for CW-only (Morse code) operation, so a much smaller transceiver is possible if you do not require voice capability. Handheld transceivers for the 2m and 70cm bands are common. The (tr)uSDX (Fig.9) is a five-band/ multimode QRP transceiver in a pocket format (90×60×30mm & 140g). It is an open-source kit, but there are many suppliers; make sure they are selling the authentic product as specified on https://dl2man.de/ The Quansheng UV-K5(8) (Fig.10) is an extremely cheap handheld transceiver that works on the 2m and 70cm bands at 5W. There is an enormous online ham community writing custom firmware for it; if you buy one, get a programming cable too. Some low-quality transceivers are available with unfiltered outputs that can interfere with other services. Be wary of fake equipment of all varieties, especially antennas. To name just two examples, an enormous number of fake “Nagoya” and “Diamond” brand antennas are available online. Don’t ruin your experience, and possibly your radio, with a fake; buy from reputable dealers. Note that transceivers imported from Japan or elsewhere might not conform with amateur bands in Australia and usually cannot be converted to do so, even if a similar model is sold here. So check first. Antennas Along with your transceiver, the antenna is a vitally important item. Antennas are usually cut to a specific length to resonate at a particular frequency or a range of frequencies, although there are also non-resonant designs. The basic antenna types are: • the dipole (Fig.11) or folded dipole antenna, half a wavelength long • the vertical antenna (Fig.12) with a ground plane • the Yagi (Fig.13), which is highly directional Other options The Elecraft KX3, Xiegu X600 and Lab599 TX-500 are other portable rigs worth considering. The Yaesu FT-710 AESS is a 100W base station radio with a built-in antenna tuner; it is worth considering for a beginner. It has a price and features similar to the Fig.11: a dipole antenna. Original source: www.arrl.org/single-banddipoles siliconchip.com.au Australia's electronics magazine April 2024  29 Fig.12 (left): a field-expedient vertical antenna supported by a squid pole. Source: www.vk5pas.com/squid-poles.html Fig.13 (below): David’s Yagi antenna (on the left; the TV antenna on the right is also a Yagi). • the end-fed antenna, one of the simplest and easiest to get started with • the magnetic loop antenna (Fig.14) There are vast numbers of variations on all of those designs. All antenna designs have advantages and disadvantages; there is no perfect antenna. For example, dipole antennas are large, especially for the lower HF frequencies. Magnetic loop antennas have a narrow resonance range (high Q) and must be retuned as you make slight adjustments to the frequency (some can do this automatically). It has been said that “the best antenna is the one you have at the moment”. Any antenna, no matter how primitive, is better than nothing; even a 10m or so length of random wire with an antenna tuner is better than nothing and can get you on the air. The higher off the ground it is, the better. An important consideration for an antenna is the take-off angle. Operation near salt water also significantly improves range. There is a German brand of thin wire for portable antennas called DX-Wire (www.dx-wire.de), which is lightweight and contains reinforcement. Quality antenna wire can be obtained from DXCommander (siliconchip.au/ link/abss). However, by all means, try regular wire for your antenna experiments. Some people swear by speaker wire, split in two to double your length! Antenna couplers/tuners can be purchased or made yourself. One DIY design by Peter Parker VK3YE is shown in the video “Yet another QRP L match antenna coupler” at https:// youtu.be/JwVuvu-C30c You can search YouTube for “VK3YE coupler” without quotes to find his other designs. It is possible to generate hundreds of volts on an antenna during transmission, so as a safety measure, they should not be touched during transmission and should be kept out of reach of people and animals. You can simply follow some basic rules to make your own basic dipole or long-wire antennas. However, experimenters can model more advanced designs with free software such as MMANA-GAL. A free basic Windows version for non-commercial use is at http://gal-ana.de/basicmm/en/ (see Fig.17 and the video “Our Obsession with Ham Radio Antennas” at https:// youtu.be/MSNvaDzCA1c). Fig.15: David’s radio shack (not the author). Fig.16: Stan “Stax” Schwartz (www.qrz.com/ db/KE5EE) lives in Molina, Florida and has an impressive antenna farm and shack, the latter shown here. If you have the money and the land, why not? 30 Silicon Chip Australia's electronics magazine siliconchip.com.au antenna made from power line cable and hardware, as it is designed to support such great spans. See the video titled “HAM RADIO MONSTER ANTENNA – ZL3SV” at https://youtu. be/7ah95zW9-WM and his website at https://angelsnz.net/zl3sv.htm A local ham, David, showed me his shack (Fig.15) and Yagi antenna (Fig.13). Standing wave ratio (SWR) Fig.14: a magnetic loop antenna. Source: https://w.wiki/93Y4 (GNU FDL). Another free antenna modelling program is 4nec2 (www.qsl.net/4nec2). For a Linux version of NEC2, see www. xnec2c.org EZNEC (https://eznec.com) is also free and has many tutorials, but there is no support or updates from the author, W7EL, as he has retired. There are also many online calculators and software for all aspects of radio ham activities. Generally, resonant antennas can be shortened to half or a quarter of a wavelength; fractions such as one-third or one-eighth are unsuitable for various reasons. An end-fed antenna should not be one-quarter wavelength long, as described online at siliconchip.au/ link/abst and siliconchip.au/link/absu Amateur Gary Watson, ZL3SV in New Zealand has a 640m-long The SWR measures the amount of power the antenna reflects back to the transceiver. Such power is not propagated, so the SWR should be kept as low as possible. It is minimised by correct antenna tuning and the correct use of baluns or ununs (more on them later). In general, aim for an SWR of less than 1.5:1, which indicates a 4% power loss. 2:1 represents an 11.1% power loss, while 3:1 is a 25% power loss. For much more detail on this, see the PDF at siliconchip.au/link/absv DIY end-fed antenna projects The end-fed antenna is just a length of wire that may or may not be resonant depending on the frequency and whether it is fed via a balun or antenna coupler/tuner. If resonant, it can be a half-wave antenna, a so-called EFHW (end-fed half-wave). The end-fed antenna is very versatile and cheap to make. One example is in the article by Peter Parker VK3YE at siliconchip.au/link/absw A good video about end-fed antennas titled “End Fed Antennas – Portable, Emergency, Stealth Installations” is at https://youtu.be/Fk2vahBnfbQ Another simple end-fed antenna project from EARC is described in the PDF at siliconchip.au/link/absx A “squid pole” is like a telescopic fishing pole and comes in lengths up to around 10m. It is suitable for elevating lengths of lightweight wire (like hookup wire) for use in portable operations or even for home use (as I am currently doing). The Haverford squid pole is an example; see siliconchip. au/link/absy Not all wire lengths are ideal for end-fed antennas. The best lengths are discussed at siliconchip.au/link/absz Antenna analysers A vector network analyser (VNA) was, until recently, an extremely expensive item of laboratory equipment to measure the amplitude and phase of a signal as it goes through a circuit. Such devices are now available to hobbyists at affordable prices. Of course, hobbyist-grade VNAs are not as good as expensive laboratory devices but they are still useful. They are great for various amateur radio applications, such as measuring antenna SWR, impedance, frequency response, cable losses, and filter measurements. The NanoVNA is an inexpensive VNA that uses open-source software and has a large support base. See our review from April 2020 (siliconchip. au/Article/13803). If purchasing one, make sure you get the appropriate adaptor leads for your application. Travel as a ham Fig.17: sample output from the MMANA-GAL antenna modelling software. siliconchip.com.au Australia's electronics magazine There are reciprocal arrangements with other countries to take your portable rig internationally; check with the authorities in the proposed country of travel. For overseas amateurs visiting Australia, check with the ACMA: www.acma.gov.au/ overseas-amateursvisiting-australia April 2024  31 The Mini 1300 is a similar antenna analyser, optimised for that purpose. Other devices for analysing antennas are RigExpert (https://rigexpert. com) and several from MFJ Enterprises (siliconchip.au/link/abt0). The SARK-100 is a public domain design available as various kits (https://sites. google.com/view/sark100), while the SARK-110 is a more advanced version (www.sark110.com). Antennas in difficult situations Most people are limited in how large an antenna they can use, so there are many ideas for compact antennas. Try searching for “stealth antennas” or “HOA antennas”. Some people build antennas in their roof spaces (not suitable with a metal roof or with aluminium sarking). Others use hollow, non-metallic flagpoles, although domestic flagpoles are not terribly common in Australia. There is a video titled “How to Build an All Band in an HOA Stealthy Backyard Broadband Antenna – Corey Ruth, KD3CR” at https://youtu.be/ lu3SDp7ZvXw The PDF at siliconchip.au/link/ abt1 describes a ‘broadband butterfly terminated dipole’ (BBTD) antenna, A short history of amateur radio Amateurs have been involved in radio since Hertzian waves were discovered and utilised for communications by Marconi in the 1890s, although no licence was required then. The first commercial devices for amateur radio use (transceiver and receiver) were sold in 1905 – see below. This is perhaps the first commercial ham radio set, in an advertisement from Scientific American, November 25th 1905, page 427. In 1908, US amateurs started the Columbia University Amateur Radio Club. The Wireless Institute of Australia was established in 1910. In 1912, the US Government passed the Radio Act, which restricted amateurs to wavelengths of 200m or less (1500kHz or more) to preserve the radio spectrum. Those frequencies were considered useless for commercial, military and maritime services, but amateurs discovered they could be used for long-distance communication via the ionosphere. Amateurs first communicated between the USA and Europe on 200m in 1921. After that, amateurs were shifted to shorter wavelengths, such as 150m/2MHz, as the commercial and other importance of the medium-wave bands was recognised. In 1924, three shortwave bands were allocated to amateurs: 3.75MHz/80m, 7MHz/40m and 14MHz/20m. In 1927, 28MHz/10m was added, which amateurs still use today. John Iringle was a 14-yearold ham radio operator from Chicago in 1922. He is in his shack with the equipment he made. Source: http://hdl.loc. gov/loc.pnp/ cph.3b39715 32 Silicon Chip Australia's electronics magazine invented by Bonnie Crystal KQ6XA. It is a type of ‘travelling wave’ antenna that is non-resonant and thus broadband in nature. Vertical antennas can be useful in restricted spaces. Peter Parker VK3YE discusses several designs on his YouTube channel (search for “VK3YE vertical” without quotes). These designs are typically used with a squid pole (mentioned earlier). Magnetic loop antennas are also helpful in space-restricted circumstances but are resonant over only a small range of frequencies and need constant retuning with frequency changes. See the video by Peter Parker titled “100 watt 7 MHz magnetic loop for units and apartments” at https:// youtu.be/Cv_RnLpZ9gw Lightning protection As a general rule, it’s a good idea to disconnect the antenna from your rig when it is not in use and, if possible, lower it to minimise the possibility of damage from nearby or direct lightning strikes. Lightning surge protectors are available to place in the antenna feed line to direct excessive charge buildup to ground, but are unlikely to do much in the event of a direct strike – see Fig.18. Remember that lightning strikes can travel many kilometres; there are limits to what you can do to avoid being hit. Do not operate a ham station during an electrical storm. For further information, see siliconchip. au/link/abt2 (PDF) and www.arrl.org/ lightning-protection Baluns and ununs ‘Balun’ is short for balanced/ unbalanced and describes a type of transformer used for RF impedance matching. The awkwardly-named ‘unun’ is a similar device with unbalanced windings at both ends. Some antenna designs require a balun or unun between the transceiver and the antenna, but not all do. In ham radio, a balun matches the impedance of a balanced antenna to an unbalanced feed line (like a coaxial cable). In contrast, ununs match an unbalanced antenna to an unbalanced feedline. The feedline connects to the transceiver, which has a 50W impedance. The objective is to minimise SWR and losses. Some antenna tuners require their use, as impedance matching may not siliconchip.com.au Fig.18: a lightning surge protector that can direct excessive charge buildup to the ground to minimise damage from a lightning strike. be possible with the antenna tuner alone. In other cases, such as the Icom AH-705 tuner I got with my radio, an external balun or unun is unnecessary; it appears capable of tuning and matching just about anything (within reason). A balun is stated to have a certain ratio, which relates to the ratio of turns of the windings. The impedance transforms according to the square of the winding ratio. So a 3:1 turns balun will give a 9:1 impedance ratio, allowing you to match a 450W antenna or feedline impedance to a 50W transceiver. There are a great many designs for these devices online; they are pretty easy to make, or you can buy them. They are basically a ferrite toroid with wires wound around it. One example of a DIY balun for an end-fed antenna is the “49:1 Impedance transformer for EFHW antenna” – siliconchip.au/ link/abt3 We also found an unun kit available at siliconchip.au/link/abt4 – see the video titled “TEST: Mini 49:1 UNUN (EFHW antenna)” at https://youtu.be/ OOe5EvYjiW0 Beacons The International Beacon Project (www.ncdxf.org/beacon) has a system of transmitters worldwide, including Australia and New Zealand, that send out signals for monitoring propagation conditions. The beacons transmit on 14.100MHz, 18.110MHz, 21.150MHz, 24.930MHz and 28.200MHz. Fig.19: the 324 Maidenhead fields of the world. Source: https://w.wiki/93Y6 • FreeDV (https://freedv.org), an open-source amateur digital voice mode. • FT8, supported by WSJT-X, is a popular mode for weak signal text message communications. • Echo is a mode supported by WSJT-X for moonbounce activities (see PDF at siliconchip.au/link/abt6). • PSK Reporter (https://pskreporter. info) shows reception reports for a large variety of digital modes. Map data can be seen at siliconchip.au/ link/abtg • Reverse Beacon Network (www. reversebeacon.net) maps reception reports and propagation paths from stations heard by listening stations. • VarAC (www.varac-hamradio. com) is a peer-to-peer chat program for hams developed by Irad Deutsch 4Z1AC. • WSJT-X (https://wsjt.sourceforge. io/wsjtx.html) is a software suite that can utilise many popular digital modes such as FST4, FST4W, FT4, FT8, JT4, JT9, JT65, Q65, MSK144, WSPR and Echo. • With WSPR (Weak Signal Prop- agation Reporter), a station sends out an extremely low-power digital signal that others hear and report via the internet. It enables the determination of current propagation paths. The mode is unsuitable for conversations. It is supported by WSJT-X. Some people run WSPR all the time; you can even buy a dedicated low-power transmitter to do so (www.zachtek. com/wspr-tx). You can find maps at siliconchip.au/link/abth For additional information on digital radio, see our articles on that subject in the April and May 2021 issues (siliconchip.au/Series/360). Maidenhead Locator System The Maidenhead Locator System, also known as the QTH locator, grid locator or grid square, among other names, is a system used by hams to indicate their approximate location for various applications (see Fig.19). The world is divided into 324 Maidenhead fields, which themselves are further divided into 100 squares. The locator for any address can be determined at siliconchip.au/link/abt7 Using ham radio in emergencies The large variety of digital modes that hams can use includes: • Digital mobile radio (DMR), a digital voice mode. • D-STAR digital voice mode for Icom, Kenwood & FlexRadio systems. After Cyclone Tracy hit Darwin in 1974, communications and power were lost. It was hams who first reestablished comms links to authorities. The story is detailed at https://armag.vk6uu.id.au/1984-dec-AR.html (pages 14-15). Also, from the WIA, “Amateur Radio notably handled emergency communications for the 1939 Black Friday bushfires, Cyclone Tracy in Darwin 1974, Ash Wednesday bushfires 1983, the Newcastle Earthquake 1989, and the Black Saturday disaster in February 2009. There have been numerous other rescues and searches.” The Wireless Institute Civil Emergency Network (WICEN; https://wicen.org. au) is an organisation of Australian hams that provides emergency communications in the event of a failure of public communications infrastructure. The Bendigo Amateur Radio and Electronics Club (www.barec.net.au) also practices emergency preparedness. A report on one of their exercises is at siliconchip.au/link/abtd siliconchip.com.au Australia's electronics magazine Digital modes April 2024  33 Field Fig.20: how a Maidenhead locator specifies a location. Source: https://w.wiki/93Y7 Square Subsquare Longitude Extended square Extended square Latitude Subsquare Field Square Fig.21: Hiro, VK3EHG demonstrates ‘working’ an amateur satellite. Entering the Silicon Chip office address gives a grid square ID of QF56pf. The coding of the Maidenhead locator is demonstrated in Fig.20. There are four pairs of numbers; the subsquare and extended square pairs are used for additional precision. handheld rig. Satellite QSOs were demonstrated at the recent Rosebud Radiofest near Melbourne by Hirotaka (Hiro) Horiuchi, VK3EHG (see Fig.21). It is also possible to use SSTV to contact hams on the International Space Station. Amateur radio activities Distance records A complete list of VHF and UHF distance records for Australia is available at siliconchip.au/link/abti A record was set in the 50-54MHz band at 28,397km, between VK6JQ and TL8MB. In the THF band at 324GHz, the longest distance obtained was The following is a small sample of possible activities apart from QSOs (conversations) and digital modes. Amateur satellite It is possible to contact other hams via satellite with as little as a between VK3KH and VK3XPD with a range of 25m (they probably could have just shouted!). Field days There are many field day contest activities. Typically, the objective is to make as many contacts as possible on given frequencies. One I visited at McLaughlins Lookout in the Wombat State Forest was run by EMDRC member Peter Forbes VK3QI, about 80 minutes’ drive from Melbourne. The contest was run for VHF and UHF frequencies 50MHz to 24GHz. Around 500 contacts were Fig.22 (left): a partial view of the (foggy) Field Day site showing some antennas, including two dishes and an equipment van. The top dish has a 24GHz amplifier and transverter behind it, while the lower dish contains preamps and an antenna for 1.2GHz – 10GHz. Fig.23 (below): the transverters and amplifiers for 1.2GHz to 10GHz. 34 Silicon Chip Australia's electronics magazine siliconchip.com.au made over the 24 hours of the contest – see Figs.22-24. Hamfests and radiofests You can find a schedule on the Hamfests Australasia Facebook page (siliconchip.au/link/abt8). Moonbounce This activity is for advanced amateurs. Signals are bounced off the moon and returned or used to establish contact with other amateurs. There is an ABC news story about an Australian moonbounce pioneer Ray Naughton, VK3ATN at siliconchip. au/link/abt9 Another Australian pioneer was Doug McArthur VK3UM – siliconchip. au/link/abta Outdoor activities IOTA, Islands On The Air (www. iota-world.org) “...promotes radio contacts with stations located on islands around the world...” POTA, Parks On The Air (https:// parksontheair.com/) is “...for international portable amateur radio operations that promote emergency awareness and communications from national/federal and state/provincial level parks.” SOTA, Summits On The Air (siliconchip.au/link/abtb) “...is an award scheme for radio amateurs and shortwave listeners that encourages portable operation in mountainous areas.” Amateur radio organisations and societies ● Wireless Institute of Australia (WIA; www.wia.org.au) ● New Zealand Association of Radio Transmitters (NZART; www.nzart.org.nz) ● American Radio Relay League (ARRL; www.arrl.org) ● International Amateur Radio Union (IARU; www.iaru.org) ● Australian Ladies Amateur Radio Association (ALARA; www.alara.org.au/index.html) ● The Radio Amateur Society of Australia (RASA; https:// vkradioamateurs.org) Radiosondes Some hams track, find, reprogram and repurpose radiosondes launched by the Australian Bureau of Meteorology (BoM) for weather measurements (see Fig.25). For example, they launch radiosondes twice daily from Tullamarine airport. They can be tracked via https:// sondehub.org and they eventually come down. If found, they can be reprogrammed and then used for ham balloon launches, radio orienteering (ARDF; https://ardf.org.au), or “foxhunting”, where one or more of these devices are hidden in the bush, and others have to find it. Note that these items are disposable, and the BoM does not want them back. WWFF “The WWFF program encourages amateur radio operators to operate portable equipment from designated parks and/or protected nature areas Fig.24: a ham radio operator using a transceiver inside the equipment van. siliconchip.com.au Australia's electronics magazine around the world...” (visit the www. wwffaustralia.com). Hamclock Hamclock (siliconchip.au/link/abtj) is a free app for the Raspberry Pi and other Unix-like systems that provide important information for hams. Specialised bands Specialised bands available to advanced amateurs, such as 2200m (ULF, 135.7-137.8kHz), 630m (VLF, 472-479kHz) and bands between 23cm (UHF, 1240-1300MHz) and 1.25mm (EHF, 241-250GHz). They usually require custom-made equipment, although the recent Icom IC-905 allmode microwave transceiver covers 144MHz (2m), 440MHz (70cm), 1200MHz (25cm), 2400MHz (13cm), 5600MHz (5cm) and 10GHz (3cm). That concludes our article, to find out more, we have placed useful links, YouTube channels and videos in a PDF SC (siliconchip.au/Shop/6/376). Fig.25: a disassembled Vaisala RS41 radiosonde, a type that can be reprogrammed. Source: https://0xfeed.tech/2022/05/ repurposing-vaisala-rs41radiosondes-for-amateur-radio-highaltitude-balloon-tracking/ April 2024  35