Today, it is 350 years since Isaac Newton (1643 – 1727) sent the world’s first journal article to Henry Oldenbourg (1615-1677), secretary of the Royal Society of London, on 1672-02-06. It was about telescopes, and optics more generally. While authorship is important, Oldenbourg is historically important for introducing the concept of peer review to scientific writing.
Newton writes, “To perform my late promise to you, I shall without further ceremony acquaint you, that in the beginning of the Year 1666 (at which time I applyed my self to the grinding of Optick glasses of other figures than Spherical,) I procured me a Triangular glass-Prisme, to try therewith the celebrated Phaenomena of Colours. And in order thereto having darkened my chamber, and made a small hole in my window-shuts [shutters], to let in a convenient quantity of the Suns light, I placed my Prisme at his entrance, that it might be thereby refracted to the opposite wall. It was at first a very pleasing divertisement [diversion], to view the vivid and intense colours produced thereby; but after a while applying my self to consider them more circumspectly, I became surprised to see them in an oblong form; which, according to the received laws of Refraction, I expected should have been circular. They were terminated at the sides with streight [straight] lines, but at the ends, the decay of light was so gradual, that it was difficult to determine justly, what was their figure; yet they seemed semicircular.”
Of course, if one looks hard enough one can always find predecessors to almost everything. Thus, most historians working in the area add the adjective, modern, to the noun, review. In this way they can forget about the more original contribution made by Adab aț-Ṭabīb, = Morals of the physician, where modern readers could use practical ethics to replace morals, in the title. It was a historical Arabic book written by Al-Ruhawi, a 9th-century (probably) Nestorian physician who regarded physicians as guardians of souls and bodies. The twenty chapters of the work encompassed various medical topics, influenced by the works of Hippocrates and Galen.
In a weblog post titled Amateur Radio (2021-10-02), I confessed that I didn’t ever expect my radio equipment inventory to include a conventional amateur radio transceiver = sender and receiver.
Within a week of writing that, a radio that filled me with nostalgia was offered for sale, a Drake TR7. This is a 40 year old machine, that lacks many of the refinements/ finesses of a modern receiver. Unfortunately, it sold before I could purchase it. This was disappointing.
However, a more modern machine, an Icom IC-746, only about 20 years old, appeared in the same advertisement. It had a lot more refinements. Yet, it too was sold. This was actually a relief.
After a meeting of the Inntrøndelag/ Inner Trøndelag local group of the Norwegian Radio Relay League on 2021-10-21, I visited LB2KE (= a Norwegian amateur radio callsign) Svein Kåre Stubskin Tangen, leader of the local group. I ended up with a Ten-Tec (Tennessee Technology) Argonaut 505, with serial number 388, a transceiver from 1969 – 1973, a fifty year old machine, later paying NOK 350 for it. This machine belonged to LA8WG Jan Tverfjell, a silent key = deceased member of the group.
On Monday 2022-01-10, Alasdair and I visited Svein Kåre Stubskin Tangen again and came home with much more equipment originating with Jan Tverfjell, for NOK 500. This includes at least 2 x 2-meter band radios, an antenna matching unit = antenna tuner (AT), plus numerous small parts that may come in useful, at some time in the future. This equipment will be sorted and tested. Some of will be repaired, other pieces will be stripped into component parts.
I don’t need the 2-meter band radios, having one already, a gift from Alasdair. However, they can be useful in the recruitment of new amateur radio operators. I intend to give them away to people I know, and have encouraged to take their licence. I expect most of these will be women. In general, men have no inhibitions about buying hobby equipment for themselves. If one looks at the two genders, one finds very divergent purchasing patterns, in Norway and I suspect in Canada and USA! For example, I have managed to convince myself that I need 7 distinct types of electric saws to serve multiple use situations. These have all been purchased.
Patricia, my wife, manages to survive without any electric saws. In contrast, her knitting needle collection is large (easily exceeding 200). If I feel a need to knit, which I last felt working at Verdal prison in an attempt to break down stereotypic behaviour, I borrow needles from her. If she needs something cut with a saw, she typically enlists me to undertake the operation. With amateur radio, I expect that a lot of women would have difficulty justifying the purchase of a radio to themselves. It would be much easier for them to accept one as a gift.
I would like to encourage other radio amateurs to engage in similar behaviour, perhaps with a give it forward proviso. Radio recipients should be encouraged to give away equipment that is replaced, to someone new, without equipment. In other words, don’t give equipment back, give it forward. This concept can be traced back to Menander’s (c. 342/41 – c. 290 BC) play, Dyskolos = The Grouch, performed in Athens in 317 BC. Other people/ works expressing the concept include: Ralph Waldo Emerson (1803 – 1882), Compensation (1841), Lily Hardy Hammond (1859 – 1925), In the Garden of Delight (1916), and Robert Heinlein (1907 – 1988) Between Planets (1951). More recently Catherine Ryan Hyde (1955 – ) expressed it in her novel Pay It Forward (1999), which was made into the film of the same name in 2000, directed by Mimi Leder (1952 – ). There can be good reasons for keeping old equipment, including sentimentality. Thus, it is important that people do not allow themselves to be bullied into giving away/ selling equipment.
I am back to Plan A, the DIY/ homebrew/ home made rack-mounted HF = high frequency transceiver, that could provide different modulations, including SSB = single side band (a power-saving form of AM = amplitude modulation), FM = frequency modulation, and digital modes. VHF = very high frequency/ UHF = ultra high frequency are not being considered at the time. Nor is CW = continuous wave = Morse code .
Quaint fact: Amateur radio equipment has traditionally used 13.8 V as its standard voltage. In the circles I frequent, and to add to any confusion, this is pronounced, twelve volts.
As I prepared to write this post, my mind returned to the mid 1960s, and to the electronics classes I was taking. Making devices at that time was a much more complex undertaking, because electronic components were needed to implement many more different types of operations. Today, these can be programmed in software. Once a program is made, it can be used on countless other devices. This explains one reason for the popularity of not just software defined radio, but many other products.
The reasons for Plan A are relatively simple. However, there are general reasons, and personal reasons.
Until the beginning of the new millennium, most living rooms were only half social environments. The other half of the space was active storage. Music was stored on LP records or CD disks. Playing that music involved a number of devices: a turntable, an amplifier and at least two speakers. There were also books that were stored in a paper format on shelves. A television brought a signal into the living room. After a few decades, assorted recorders and playback machines allowed viewers to record programs, and to save them for later viewing, on VHS/ Betamax cassettes, then DVDs. Photography involved a camera, film, processing, slides/ negatives/ prints (depending on film type), photo albums/ slide storage containers, slide projector and screen, with extra bulbs.
Today, music, books and other forms of literature, audio-visual products including documentaries, television episodes and movies, and photographs can all be stored on and transferred to a variety of devices, included servers/ handheld devices such as phones and tablets/ laptops/ desktops/ wallframes. The last one is a new name for a screen that used to be called a television, that can be used to display static images, when not being used to show moving pictures! Life is so much simpler, with less hardware. Apart from professionals, everyone else takes photos with their favourite hand-held device.
As in these other areas of life, radios too are becoming less hardware and more software. The challenge comes with the educational opportunities of radio operators. In North America, until about 1970, there was a strict sexist divide, that required boys to undertake industrial arts: woodworking, metalworking, electronics and draughting. At the same time girls were prohibited from taking these subjects, but were offered home economics courses: cooking and textiles, that were unavailable to boys. Later, both genders were allowed to select from both sets of subjects. In addition, new subjects gradually emerged to supplement and to a certain degree replace, these older ones. These new subjects included automotive mechanics and computer science/ programming.
My most important personal reason is that my office occupies an area of less than 4 square meters. Even with an expansion consisting of a new 1 500 x 300 mm shelf populated with 3 Ikea Moppa, mini-storage chests, and a 320 x 300 x 140 mm Biltema assortment wallbox, there will not be an excessive amount of room for radio equipment.
Related to this is my approach to tools. While I still have a number of self-contained tools, such as multimeters, that operate independently of a computer, I prefer tools that share components. An oscilloscope provides a good example. It is an electronic test instrument that graphically displays waveforms. Even today, these instruments frequently have their own built-in displays. Yet, why should one invest in yet another display, when every desktop computer already has one. For a person with some vision issues, a large, adjustable display is a much better solution. In addition, using a computer to process data and to display graphics is one way to save money, that could be invested in a more precise instrument.
Thus, I plan to build my own radio hardware including amplifier using commonly available electronic components and store it inside a rack located away from the office, in the basement, that houses our NAS server. This halves the distance from my desk to the antenna/ flagpole, but necessitates the use of remote access procedures to operate the radio. The rest of the radio will be made in software, and stored inside one or more computers.
Similarly, there is no need for physical dials and switches, when these can be implemented as part of a graphic user interface, that use a keyboard and pointing device, if not a touchscreen. Apart from reserves that should be kept on hand in case something breaks, there is no need for more than one microphone, or one headphone set.
Amateur radio can be an enjoyable hobby, but one should know what one wants to get from it, before starting. It can be an effective tool that can be used in emergency situations. Some people are interested in actually communicating with others. Many have little interest in people, but like to win competitions. Another group avoids people altogether and concentrates on building radios and other components.
Personally, I am more interested in the equipment than any communication. I am more interested in digital capabilities than voice, especially using QRP = low powered equipment. However, I also have an interest in experimental (audio-)visual communication, involving both still images and video, especially for use in emergency situations.
In terms of instruments, I have found that a Red Pitaya could act as my primary workbench tool. It saves workbench space by being able to perform multiple functions. It attaches directly onto a computer with screen that is already taking up workbench space.
Radios require antennas. There are many different types, some suitable for specific bands, but not others. These have to be built to match the type of activity envisioned. We are considering an HF antenna suitable for several bands, that can built into/ operate from our 8 m high fibreglass flagpole.
Warning: the remainder of this post is more technical. Some people may prefer to hop over the details of amateur radio communication.
The Ten-Tec Argonaut 505 transceiver is a pure QRP machine, with 5 W out, 13.8 V and 1.2 A in. Some work remains before it is ready to receive or to transmit. A microphone has to be adapted to fit the line input on the radio. There was no power supply unit (PSU) with the machine. Fortunately, I have a 0 – 30 V, 0 – 5 A linear PSU, that should do. Antenna components have been acquired, but are not yet in place.
19-inch racks: A 19-inch rack is a standardized frame or enclosure for mounting multiple electronic equipment modules. It was developed by the American Telephone & Telegraph Company in about 1922, making it 100 years old. Each module has a front panel that is 19 inches (482.6 mm) wide, including protruding edges/ ears on each side, that allow the module to be fastened to the rack frame with screws or bolts. The height of a rack is measured in Us, with 1U = 1.75 inches = 44. 45 mm high. A full height rack is 42 U tall. Such units typically occupies data centres, and corporate offices.
The rack in our basement is half-height = 21 U. The length of the unit is 800 mm. The top of the rack has been transformed into a desktop, which holds a computer screen, mouse and keyboard, plus an assortment of tools. The top of the rack/ desk is 1010 mm off the ground.
The rack currently has a lot of vacant real-estate, probably in excess of 10 U. Thus, new equipment could (theoretically) occupy 400 litres. I suspect that a radio should not occupy more than 2 U in height, or about 80 litres. In contrast, an Icom IC-746 occupies about 11 litres, and weighs about 9 kg. This means that using a rack there is no need for excessive miniaturization. A shelf 250 mm long has been fitted, but could be augmented or replaced with longer shelves if necessary.
There are two ways in which radio frequencies are described. The first is to use the frequency itself. There is a certain amount of imprecision used in amateur radio slang. high frequency (HF) is very specific both in terms of frequency (3 to 30 MHz) and wave length (100 to 10 m). However, a HF receiver will typically take in signals from 0.03 – 60 MHz, with wavelengths from 10 000 m to 5 m. A VHF receiver would take in frequencies 300 to 30 MHz, of which 144-148 MHz, covers the main amateur radio FM band. Signals in the VHF range have wavelengths of 10 to 1 meter
For radio transmission, specific bands are set off for different purposes, including amateur radio. Once again, the bands represent the wave lengths: 160 m = 1.800 – 1.999 MHz (technically, this is MF = medium frequency but is often clumped together with the HF bands); 80 m = 3.500 – 3.999 MHz; 40 m = 7.000 – 7.300 MHz; 30 m = 10.100 – 10.150 MHz, a popular HF band; 20 m = 14.000 – 14.350 MHz, another popular HF bands; 17 m = 18.068 – 18.168 MHz; 15 m = 21.000 – 21.450 MHz; 12 m = 24.890 – 24.990 MHz; 10 m = 28.000 – 29.700 MHz; 6 m = 50.000 – 54.000 MHz (Wavelengths between 10 and 1 m are in the VHF = very high frequency range); 2 m = 144.000 – 148.000 MHz (One of the main FM transmission bands).
Some of the bands are more important than others. For DX = typically, intercontinental communication, one would want to use bands with longer band widths, possibly 40 m. Shorter wave lengths are useful for more local communication.
Alasdair, my son, owns a Red Pitaya with a transceiver. It is often described as a Swiss army knife for engineers. It can replace many different instruments including: oscilloscope, to visualize wave forms; LCR meter, for measuring the characteristics of passive electrical components: R = resistance, C = capacitance, L = inductance and Z = impedance, and many more; spectrum analyzer, that measures the quality of signals; logic analyzer, for digital signals; Bode analyzer, that measures frequency responses in electronic circuits; and, a Vector Network Analyzer, used to test and optimize the performance of radio frequency components, such as antennas and cables.
Disruptive changes are happening throughout the technical world. At the end of 2021-12 Canon Chairperson/ CEO Fujio Mitarai stated: “Canon’s [single-lens reflex =] SLR flagship model is known as the ‘EOS-1’ series, the first of which appeared in 1989. The latest model ‘EOS-1D X Mark III’ released in 2020 will be the last model in fact.” PetaPixel, a photography news website, then predicted that both Canon and Nikon would not invest in new digital SLR cameras, which are bulky, in part because of their use of mirrors, and are now focused on the mirrorless camera market. They said they would be surprising if either company released a new SLR model in the future.
Initially, the language used in pre-college computer science was Logo, a programming language specifically designed for teaching in 1967 by Wally Feurzeig (1927 – 2013), Seymour Papert (1928 – 2016) and Cynthia Solomon (1938 – ). Logo is from the Greek logos, meaning word or thought. It used turtle graphic commands to move a floor/ screen robot (turtle).
Squeak an object-oriented, class-based, and reflective programming language derived from Smalltalk-80, and released in 1996, and Scratch, a high-level, block-based programming language, first released in 2003, have largely replaced Logo. They are more sophisticated than Logo, but I am not convinced that they are any better at teaching programming concepts. In fact, their complexity makes them worse.
This means that older men may have more of a focus on electronics and the hardware aspects of radio, while younger people may be more focused on programming and the software aspects of radio. Thus, before computers became part of everyday life, electronics and the construction of radios, often from kits, was an acceptable hobby. The difference between electronics as a hobby in, say, 1980 and from 2010, is mainly in the use of microprocessors, or their less powerful microcontroller relatives, especially built onto boards. Since about 2010, the Arduino Uno board has been a major focus. However, the AVR chip used on it does not meet the requirements needed in an amateur radio system. The Raspberry Pi is a much better match. Some people also make receivers with Teensy microcontrollers.
While I am fond of unusual programming languages, especially for my own personal projects, using one is not always the best approach if a community of users is expected to work together. My prejudiced opinion is that currently there are only two families of languages that are suitable for a community building the software components of a radio. These are C (and its derivatives, including C++) and Python. People who do not already have a sizeable investment in C, developed in 1972 by Dennis Ritchie (1941 – 2011) at Bell Telephone laboratories, Murray Hill, New Jersey, are encouraged to use Python, developed by Guido van Rossum (1956 – ) in 1991, who was working at Centrum Wiskunde & Informatica (CWI) = the Dutch national research institute for mathematics and computer science, in Amsterdam.
Technological Education: Before & Beyond Code Club. A second weblog post with a focus on amateur radio.
We live in a world of celebrities, where people with influence attempt to promote activities they know little about. My favourite celebrity, for illustrative purposes, is Paris Hilton (1981 – ), who is world famous, for being famous. Much further down the list is Clare Sutcliffe who, with Linda Sandvik, developed Code Club in 2012. They, and Code Club, are world famous for trying to teach children, aged 9 to 13, to programme or, at least, write code. They know a little about children, and a little about programming. I am not certain how much they know about teaching children.
As noted before in previous weblog posts, in Scandinavian teacher education, Lev Vygotsky (1896 – 1934) is probably the most important theorist. His Zone of Proximal Development (ZPD), is the range of tasks that a child is in the process of learning. While some level of proficiency (the ZPD lower limit) is possible with the child working independently, higher skill levels can be reached with teacher assistance. The teacher’s role is to construct a learning scaffold, a support that allows the child to develop confidence and capability. Over time, the scaffolding is gradually removed, until – once again – the child works independently.
In North America, a related concept is that of a teachable moment, that was popularized by Robert Havighurst (1900 – 1991) in Human Development and Education (1952). “A developmental task is a task which is learned at a specific point and which makes achievement of succeeding tasks possible. When the timing is right, the ability to learn a particular task will be possible. This is referred to as a ‘teachable moment.’ It is important to keep in mind that unless the time is right, learning will not occur. Hence, it is important to repeat important points whenever possible so that when a student’s teachable moment occurs, s/he can benefit from the knowledge.”
Swiss developmental psychologist, Jean Piaget (1896 – 1980) argued that children develop abstract reasoning skills in their last developmental stage, the formal operational stage. He suggested this occurs between the ages of 11 and 16. Many educators make an arbitrary choice, which is the beginning of junior secondary school. Before this age there should be a focus on the concrete, and the physical.
The key to teaching technology is to find a suitable start point for abstract thinking. Programming, like many related tasks, requires abstract thinking. Many in that 9 to 13 age group are just not mature enough, and will find the tasks impossible, potentially putting them off programming forever.
With Code Club there is no focus on either scaffolding or teachable moments or an ability to think abstractly. It appears to be unsystematic in its approach using Scratch, HTML & CSS, Python and a variety of other coding languages. In certain jurisdictions, the initiative also provide free BBC Micro:bits to children above the age of 9, this provides a potentially disingenuous economic incentive.
Code Club states that its purpose is on children having fun, while coding games. My experience is that children are less motivated by fun, than by an opportunity to be of service, and to be respected for their mature behaviour.
Games have other negative aspects. There is a potential for lifelong gaming addictions. On 2021-08-30, China introduced new restrictions to limit the time under-18s can spend online gaming. They may only play on public holidays, Fridays, Saturdays, and Sundays from 20:00 to 21:00. All online games have to link with a state anti-addiction system. In the west there seem to be no limitations imposed despite the fact that many students are unable to remain awake in their classrooms, because they have spent their entire nights gaming. Games are addictive. Code Club originally wanted to limit its activities to one hour a week. However, not all children (or their parents) are in agreement with this.
Relying on games is also problematic, because they are divorced from reality. They can blur moral boundaries, allowing players to choose between being good or evil or somewhere inbetween. I am in agreement with Chinese authorities that games should not give players this moral choice.
Another challenge relates to the evaluation of game quality. Any discussion can be treated as a subjective opinion. There is seldom any tests of correctness that can be applied. This contrasts with physical computing where the programming is incorporated inside an electromechanical device that has to serve a purpose, and there are metrics that can be used to determine if the goals incorporated into the device have been achieved.
On a more positive note, game-related tools, such as simulations, can be useful in teaching subjects as diverse as social economics, and ecology.
In terms of preparation for learning, there are three key things parents can do. They can ensure that children eat healthily, sleep sufficiently and are physically fit. In elementary school (typically grades 1 to 7) one approach is to focus on outdoor activities that encourage endurance (stamina), strength, mental well being, an understanding of the natural world, and an appreciation of other human beings.
As an example, these concepts will be applied to amateur radio.
Teaching typically relies on a curriculum that shows how various activities mesh together in a comprehensive whole, to provide insights and knowledge to students. This allows any teacher to know the specific educational goals to which s/he is working, so that s/he can choose the most appropriate pathway. In terms of amateur radio, this means knowing which components, ICs, MPUs and programming languages are going to be used, and why.
In amateur radio, the most popular FM communication frequencies are restricted to line of sight. This means that local groups often build repeater stations on high elevation points at remote locations that can facilitate communication over longer distances. These repeater stations are typically not on the grid. They need power from some local source, a battery rechanged with a generator powered by an engine using tanks of propane gas, a miniature windmill or a solar panel. Regardless, these will need to be inspected and serviced at regular (typically annual, intervals). Thus, one activity is to encourage younger children to accompany adults, walking the trails that lead to the repeater stations to check them out, and service them if required. At the same time they might learn something about FM communication, batteries and other equipment through osmosis. Older children might even be able to carry some of the equipment needed, and thus feel even more useful. At some point the child will be in a position to actually undertake the complete servicing.
The fabrication of antennas is another area where children might be able to participate. Under adult supervision, they can be given a diagram of the antenna to be built, with instructions detailing the lengths of wire to be used, and how they are to be attached to black boxes, more generally called baluns and traps in radio circles, which are needed to make antennas function optimally. Here the skills needed will be physical, an ability to measure, mark, cut, fasten and assemble. All of these activities require the use of simple, non-electric hand tools. Fabrication provides an opportunity for children to learn work safely, to be orderly, systematic and accurate, and to have respect for other people and tools. It can also teach the value of cleanliness, in that workshops have to be cleaned regularly.
This list is far from complete, and I would ask that radio amateurs and others who have ideas for activities suitable for children to contact me with their suggestions.
In terms of more abstract activities, I would certainly not begin with programming, but with electronics. Electronics has become a simpler subject since the introduction and wide scale adoption of transistors, integrated circuits (ICs) and microprocessor units (MPUs). That said, it is often easier to program a solution, rather than to develop a circuit. However, one must understand the advantages and limitations of both, starting with electronics.
One understandable electronics textbook is Electronics: A Self-Teaching Guide (1979) by Harry Kybett. This was followed up with a second edition in 1986. The third edition appeared in 2008, that had its title changed to All New Electronics Self-Teaching Guide. It also added Earl Boysen as co-author. The latest edition is Complete Electronics: Self-Teaching Guide with Projects (2012). Here, the order of the authors is reversed, Earl Boysen and Harry Kybett. I used the third edition as my main source of electronic information, for the last years of my teaching. However, when in doubt I do check information with more recent, typically online, sources.
Another book that attempts to impart basic electronic insights is Make: Electronics (2009) by Charles Platt (1945 – ). It is the hands-on experimentation that makes this book valuable. This was followed up with Make: More Electronics: 36 Illustrated Experiments That Explain Logic Chips, Amplifiers, Sensors, and More (2013).
Microprocessors have existed since the Intel 4004 was released in 1971. There have been any number of microprocessors used to teach aspects of computing. There are many other families of microcontrollers that may be used to solve real-world challenges, including the construction of radio circuits. These include BeagleBone, ESP, and Teensy. However, since 2005, three families of microprocessors have attracted attention for educational purposes. These are: Arduino, Raspberry Pi and Micro::bit, in release date order.
Of these, Arduino is the oldest of these, and shows its age and limitations, although it does have some excellent attributes. Despite its limitations, the Arduino can be an appropriate place to start learning, especially if one has an Arduino based starter kit of electronic components. In 2011, Jeremy Blum made a number of video tutorials, introducing people to Arduino. I used these extensively in my teaching. He developed projects where components are fitted onto a breadboard, and then joined to ports on the Arduino including ground (negative) and 5 V power (positive). The Arduino is connected to a power supply connected to household current.
Blum wrote a book Exploring Arduino (2013), second edition (2019). Radio amateurs should note that chapter 15 in the second edition discusses wireless radio frequency (RF) communication, providing a useful introduction to the electromagnetic spectrum, and the use of RF to control assorted devices, such as doorbells, lamps, and relays. The next two chapters discuss Bluetooth communication and WiFi communication, respectively.
One important family of Arduino devices are shields. These are printed circuit boards with various components already installed on them, capable of performing a specific function. They fit onto an Arduino board without any wiring or soldering.
Micro::bit is a political project, organized by the British Broadcasting Corporation. Because they wanted to ingratiate themselves with a large number of corporate sponsors, there is abundant choice. The Norwegian Department of Education has decided to deploy Micro::bit in Norwegian classrooms, not because of its educational merits, but because a Norwegian company had its parts incorporated into it. I am avoiding it because of some major pedagogical weaknesses.
This leaves the Raspberry Pi (RPi) as the most suitable technology for teaching about microprocessors. One of the reasons it has been adopted by teachers and hobbyists, is its General Purpose Input Output Pins (GPIO). These 26-40 pins provide a physical interface between the RPi MCU and the world, because it allows for the connection of a range of sensors/ activators/ other components typically placed on breadboards. When developed into a circuit, the components can interact with software installed on the Pi. These include a number of amateur radio applications.
RPi HATs (Hardware Attached on Top) are specially designed boards that perform specific tasks, that plug directly onto the GPIO pins. These provide the same type of function as the shields do on Arduinos. James Stevens in his MoJCQ’s Hamblog provides ten amateur radio uses involving RPis. More recently, Kedric Hart has written Coolest Raspberry Pi Amateur Radio Projects in 2021. Both of these articles have one weakness. They are reporting on projects developed by other people. Some of the projects are good, others are less good, but left unimproved. Thus, none of the projects can be incorporated into a teaching project without being reworked.
Books related to Raspberry Pis and amateur radio include: Dwight Stanfield’s Hamshack Raspberry Pi for Amateur Radio Activities (2018) and Jeremy Stephens, Hamshack Raspberry Pi: A Beginner’s Guide to The Raspberry Pi for Amateur Radio Activities (2017).
Much of the learning necessary for amateur radio activities happens when the student works on experiments. An experiment should be an investigation that allows for an exploration of a topic in some detail. Microprocessors bring a new dimension to the construction of an electronic devices. They will be made out of electronic components, but also contain code run inside the microprocessor.
Code here should be regarded as a software component. It is inserted and run, producing results that can be documented. Code can also be modified, in much the same way that a component of a different value can be substituted for another, resulting in operational changes that can be measured.
After a student has become proficient in building and modifying devices, including the software, that s/he should be encouraged to programme. There are any number of languages that can be chosen, but often these are related to the microprocessors being used. For example, Arduinos use a variety of Wiring that looks almost like C. Raspberry Pis are often programmed in Python.
Rob Thubron, in an Techspot article dated 2021-09-27, titled Some students don’t understand the concept of computer files and folders, that begins, “To readers of this site, the idea that some students on courses ranging from engineering to physics don’t know what files and folders are might seem strange, but it’s true. According to a new report, the fault lies with popular modern operating systems and devices that include all-encompassing search functions or hide file structures from plain view.”
He ends, quoting physicist/ astronomer/ associate professor Peter Plavchan, addressing fellow educators who look on aghast at students unable to comprehend filing systems, “This is not gonna go away. You’re not gonna go back to the way things were. You have to accept it. The sooner that you accept that things change, the better.”
If terms of radio technology there are going to be generational divides. Boomers (while they still exist) and GenXers will educate Millennials and GenZs in accord with their understanding of the world. Hopefully, the teachers will take to heart the advice of Lev Vygotski, and concentrate on building the scaffolding so helpful for pupils to learn. How the Millennials and GenZs respond is up to them!
Note 1: Code Club was merged into the Raspberry Pi Foundation on 2015-11-03, as a wholly owned subsidiary. On 2018-03-16, Clare Sutcliffe, then executive director at Raspberry Pi, announced she was leaving both Code Club and Raspberry Pi.
This post is being published because I have passed my amateur radio licence exam, and been issued the Norwegian call sign: LB2XJ. I am not the first person in my immediate family to have such a licence. My son, Alasdair, aka LB6HI, earned his in 2019. Both of us also have previously taken VHF = very high frequency, maritime radio certificates (now called SRC = short range certificate). The primary reason for taking this earlier certificate was to be able to seek help in emergency situations while boating, although it allows other forms of communication between boat operators. The reasons for taking this amateur radio licence are more complex, and the subject of this weblog post.
I would like to thank four people for their assistance in gaining this certificate. These are Per-Dagfinn Green (LA1TNA), Peter Ebsworth (LA7ZMA/ LB0K), Jan Stewart Rambech (LA7VV) and Robert Eliassen (LA6GHA). The first two were instructors for the online Amateur Radio course given by the Bergen Group of the Norwegian Radio Relay League, which is the national organization for amateur radio enthusiasts in Norway. The course consisted of 17 course evenings from 2021-02-03 to 2021-05-11 with 22 participants completing the course, of which 19 have so far passed their exam. Jan organized an exam for me in Trondheim on 2021-06-19, which I managed to fail. Robert organized a second exam, held at Cliff Cottage, on 2021-09-25, which I managed to pass. I would also like to thank Lars Gjøsund (LA9EMA) for his encouragement to get my ticket, as North Americans would say.
My first encounter with amateur radio was through the wolf cubs/ boy scouts at Sixth Avenue United Church, New Westminster, where one of the leaders who lived nearby on McMartin Street, had radio equipment that we were invited to see (and hear) in use. If anyone knows the name of this person or other early New Westminster radio amateurs, I would appreciate the information. Yes, I have attempted to contact the New Westminster Amateur Radio Club (NWARC) to find out if they know, as well as to find out who else I know there. However, they don’t seem to accept unsolicited emails. How they will be able to function with this approach in any sort of emergency is beyond my comprehension. Ed Frazer of the British Columbia Amateur Radio Coordination Council was able to help me, and sent my email onwards. Thank you, Ed. My experience is that some amateur radio local groups are surprisingly bad at communicating, especially when it comes to the internet. Some don’t even provide an email contact address on their website. NWARC was formed in 1996 as a non-profit society to deliver emergency communication services. The club is part of BCWARN, a provincial network of emergency operations centers (EOCs) and radio clubs, which support emergency communications.
In the 1990s, I constructed a software Morse code trainer in Pascal that ran on a PC. It would read a written document stored on a file, then produce an audio version through a speaker at a speed determined by the user. In 2002, in Molde, I undertook amateur radio studies, but quickly realized that I would not succeed, and did not even attempt to take the exam. This was because, at that time, the certificate included a requirement to communicate in CW = continuous wave = Morse code, outside of radio circles. This requirement ended in 2003. Yes, I should have used the Morse code trainer more!
In the early years of the new millennium, I was in contact with another radio amateur with my very name, Brock A. McLellan (KC8KOD), with A in his case standing for Adam. However, this communication was about our common ancestry, not radio. Information obtained more recently from my sister-in-law, Aileen Adams, leads me to believe that he and I are more closely related than I was aware of at the time. He currently lives in Bad Axe, Michigan.
If one listens to amateur radio operators, there are any number of good reasons to become licensed, including the opportunity to connect with people around the world, and to participate in any number and type of competitions. There are many different radio bands (including 160, 80, 40, 20, 6, 4, 2 meter, and 70 cm nominal wave lengths) that use different types of equipment, especially antennas, and different modulation techniques (such as SSB = single side band, a form of AM = amplitude modulation; and, FM = frequency modulation) that are used for different purposes. These opportunities were not what has attracted me. If I want to talk to someone on the far side of the world, my preferred method is to use Signal software, with a headset attached to a laptop. In addition, I have a hand-held device aka cell/ mobile phone.
Yet, there is a use for real world radio transmissions by amateurs, it involves providing emergency communication in situations where broadband internet and cell phones no longer function satisfactorily. One scenario could be a power outage leaving a community without the ability to communicate with their outside world. Personal prejudice require me to state that voice radio wastes resources in such a situation, as data-communication is much more effective. Others could argue that CW is even more effective. Regardless, in such situations electrical power becomes a critical resource, typically requiring batteries and mechanisms to charge those batteries. While solar energy is often preferred, this is not particularly useful in the winter, above 60° latitude.
Many members of local search and rescue organizations express an interest in amateur radio, until it comes time to actually learn something about it. In part, this is because they generally prioritize hands-on activities in the outdoors, rather than spending time indoors learning tedious details about electronics and radio-frequency communication. However, both types of people may be needed in an emergency situation.
For example: On 2020-12-30, a quick clay landslide occurred in the early morning hours at Ask village, the administrative centre of Gjerdrum municipality, Norway. The flow off area spanned 300 by 700 metres, but the landslide caused an additional 9 hectares of debris flow. Several buildings were destroyed, most of them houses and apartment buildings. Initially, it was thought that 30 people were missing. In the end, thirteen people were rescued, while ten lives were lost. At first, one could only look for survivors from a helicopter due to safety concerns. Then it was decided to send search crews, including dogs, into the landslide area. Each searcher was equipped with a tracker, which is useful, because then the precise location of each is known at all times. Monitoring of the searchers was performed by radio amateurs.
I don’t ever expect my radio equipment inventory to include a conventional amateur radio transceiver = sender and receiver. In part this relates to my interest in computers and software, and my obsession with miniaturization, and power minimization. In amateur radio circles this codes as QRP operation. If 1 000 W of transmission power is allowed in Canada and Norway (1 500 W in USA), then 100 W is good, but 5 W is better, and is often regarded as the defined limit for QRP, although some might allow 10 W. Extreme minimalists, willing to restrict their power to 1 W or less, code as QRPP. I am not quite at that point. Note 1: There are power limits specified by the band, type of broadcast, certificate status, and country. Regardless, one may only use the amount of power needed to communicate, which could be considerably under these limits. Note 2: One of the earliest proponents of QRP was Karl E. Hassel (W9PXW, ex-8AKG and sometime user of 9ZN, 1896 – 1975), a co-founder of Zenith Electronics, the American radio/ television manufacturer, the company that invented the remote control!
My primary interest in radio relates to education as a mechanism to make a more equitable world. At one time, our family’s major charity was an educational program for girls in countries that restricted their opportunities, such as Haiti. Then, the charity itself made it technically too difficult to route funds from Norway to them. Despite this, supporting education is a primary interest. Thus, when I think of radio it is in a context of technology that can provide educational opportunities to everyone, but especially to those who have been denied it from before. Thus, my interest is broader than amateur radio, yet more selective. It should be further noted that my interest is related to technological solutions, rather than educational content or its dispersion in the real world.
In order to make the world a fairer place for everyone, I am an advocate of open-source hardware and software. However, I am also aware that much of this software on offer is second-class. Transforming this into world-class software is challenging. I am currently developing online lectures in Norwegian on topics related to open-source hardware and software along with other computer related topics, and their intersection with amateur radio. These will be presented as part of the Bergen Group’s lecture series, held every other Monday at 20:00 CET/CEST.
Not all radio activity requires a licence. Citizen’s band (CB), known as Private Radio in Norway and much of Europe, and renamed Citizen’s radio in USA, does not have this restriction. It is a land mobile radio system allowing short-distance person-to-person bidirectional voice communication using two way radios operating on 40 channels near 27 MHz (11 meter). Some countries require users to register and to use an assigned call sign. Since 2021-09, USA’s FCC approved the use of narrowband FM modulation for the CB Radio Service, analogous to the European CEPT standard. Readers who are uncertain as to whether they want to become involved in amateur radio, may find that they want to start with CB, which could give them a taste of opportunities, despite its many shortcomings. My CB handle is Marmot.
I would also like to thank my son, Alasdair, for providing me with my first transceiver, a TYT TH-UV88 hand-held analog two-way radio operating on VHF and UHF FM amateur bands. He has a matching unit. While some people advertise these units for US$ 40, that is without anything, including postage and taxes. Thus, one should expect to pay about US$ 100 for a radio equipped for operation in the field.
This radio will soon be supplemented with a Red Pitaya STEMlab 125-14 unit for SDR = software defined radio. Alasdair has one of these. As usual, I find it convenient to buy identical equipment to people I know, so that I can take advantage of their experience and insights. SDR is often used in mobile communication. Remote software updates are used to improve hardware, update standards and implement new protocols.
Antennas and radio masts are problematic, especially for MF = medium frequency, and HF = high frequency communication. This summer, our old flag pole was removed, and a new one has been purchased and installed at a different location on our property at Cliff Cottage that should allow it to function as a radio mast. The next step is to provide a suitable coax cable connection from my desk to the base of the flagpole.
Another of my interests in radio relates to audio circuitry. Admittedly, my main audio interest relates to synthesizers, but also music more generally, including audio production (with and without video). This interest stretches back in time. In my youth I soldered together a Heathkit receiver, that eventually worked. Later, I made active speakers equipped with their own power amplifiers. My interest in synthesizers also emerged at this period, but they were far too expensive to consider making at the time. New Westminster public library was my primary source of information. In addition to many other unrelated topics, I regular read their books and magazines about electronics. My favourite magazine was Elector, which came out in an English edition, starting in 1975. After discussing it for many years, I now have a green (digital version only) subscription to it, that includes access to all back issues. I find it equally fascinating to read both new and ancient articles about the same topics, while admitting that progress in electronics is almost overwhelming.
Much of my teaching after 2008 involved the use of Arduino Uno microprocessors. The Arduino project was started at the Interaction Design Institute Ivrea (IDII) in Ivrea, Italy. These used Atmel ATmega8 microcontrollers. The AVR architecture was developed by two students at the Norwegian Institute of Technology (NTH) in Trondheim, Alf-Egil Bogen (1967 – ) and Vegard Wollan (1967 – ). For students allergic to computer hardware, I have often developed projects using Processing, a graphical library and integrated development environment (IDE) built for teaching non-programmers the fundamentals of computer programming in a visual context. Processing was developed by Chris Rea (1972 – ) and Ben Fry (1975 – ).
Because of various issues of deception related to Arduino, I have abandoned it for Raspberry Pi boards, based on Broadcom processors. The Raspberry Pi project originally promoted the teaching of basic computer science in schools, especially in developing countries. The boards are inexpensive, modular, and have an open design. They are extensively used by radio, computer and other electronics hobbyists.
People simply wanting to be entertained with amateur radio may want to see one or more of the many movies about this topic. Personally, I am currently watching films (or at least scenes) about amateurs using radios, including: Nancy Drew, Detective (1938); Handle with Care (1977), originally released as Citizens Band; and, El Radioaficionado = The Radio Amateur (2021).
For those wondering, let me state explicitly that I have no intention of raising homing pigeons. Those with an interest in these birds are encouraged to read Arthur Ransome’s (1884 – 1967) Pigeon Post (1936), the only book in the Swallows and Amazons series that does not involve some form of sailing.
I would especially like to know if any readers of this weblog are themselves radio amateurs, or are engaged in radio transmission in other ways. Readers of this post wishing to discuss amateur radio, superficially or in depth, are asked to contact me privately.
This post was originally written on 2021-05-14 starting at 22:00. It was updated immediately prior to publication.