Making goes back a long time. Lone inventors have popped up here and there throughout history, and one might even argue that the very first makers existed well before recorded history. After all, iron and copper work appear to have existed so far before written language that the only record we have of their discovery is archaeological examples of early copper and iron work.
That's not really what "makers" means though. The term "makers" is fairly recent. Makers, in the modern definition, is actually a replacement for the term "hackers", which meant exactly the same thing until the 1990s and 2000s, when it was stolen by outsiders and redefined to refer to malicious infiltrators of computer technology. By the 2010s, the "hacking" community had rebranded under the name "makers", to avoid association with criminals. The thing that distinguishes makers from early inventors is community. No, this does not include workplace community, like Edison's invention factory. Making has always been hobby first. People do it for the love of doing it, and maybe there's profit or maybe not, but profit isn't the goal. The first real maker community in the U.S., and probably the world, was actually government sanctioned, and potential for profit was restricted and regulated.
HAM radio was the first maker community. In the U.S. it was and still is governed by the FCC. When the FCC was founded to regulate the air waves to prevent them from becoming so cluttered and noisy that they would not be useful for any practical applications, it was recognized that the invention of radio technologies required a certain degree of free access to the radio spectrum, and very tight regulation would ultimately halt progress and development of better radio technologies. So Congress determined that a collection of bands scattered across the usable EM spectrum would be reserved exclusively for hobby use. These bands could not legally be used for any commercial purposes, on pain of heavy fines (which are still regularly levied against unlicensed and commercial users). To use these bands, one must obtain a license, which requires learning enough about radio physics and technology to at least potentially contribute and "make". The licensing process was delegated to volunteer radio associations. They did not just conduct the tests, they also developed the tests. When an applicant passed a test, they would notify the FCC and request a license for the applicant. This made HAM radio inherently a community. To obtain a license, one must interact with a volunteer organization that is a HAM radio community in its own right. Testing proctors come from that same community, and the test graders must be licensed members of that community. The early HAM radio licensees generally made their own radios. It took some time before radios designed for HAM bands became commercially available. Many people who decided to become licensed were inventors or hardware "hackers" in their own right, and thus the first real maker community was born.
Fast forward to today though, and HAM radio has largely been excluded from maker communities. The interest in electronics and hardware in general is still there, but HAM radio, the original makers, largely are not. Why is this? Why have the founders of making been excluded?
I suspect the answer is commercial incentive. To be clear, I'm not talking about the makers themselves. I'm talking about the companies selling products to the makers. HAM radio kind of got old as it went into the 1990s. Commercial radio technology had become too complex for the average hobbyist to DIY. FCC regulations have gotten tighter and tighter, and that has made it a lot more expensive to built a homemade radio, because now you need elaborate filters and expensive testing equipment to ensure that you do not accidentally produce signals that interfere with other frequencies. As the hobby has gotten more expensive, fewer and fewer young people have been able to even afford to build or buy radios. HAM radio began to be viewed as an "old man" hobby, because there were more older people involved than younger people, due to the high cost threshold. Through the 2000s, the situation stayed largely the same. Radios were expensive, building radios was impractical, and while more younger HAMs started to enter the scene, they were less interested in the community aspect, probably because of cultural alienation of the young from the old in most developed countries. As HAM became less popular, it grew in profitability significantly less rapidly than other things. Radioshack, originally built around the HAM radio hobby, was mostly out of the radio business by the 2000s and has all but disappeared since. Other companies that sold hardware intended for HAMs have either gone out of business or dropped or marginalized their HAM product lines. It is hard to find HAM hardware nowdays, and many of the companies that do still sell it charge absurdly high prices, because there is very little competition.
The 1990s-2000s dearth of affordable hobby radio technology has flipped now though. With the advent of companies like Adafruit, producing very low cost microcontrollers with radios built in, radio has become a lot more affordable. Unfortunately, the offerings are very limited, and there is nothing for HAMs, just things that HAMs can hack to fit their uses, if they can afford the expensive bits required to meet their needs. Audio radios are pretty cheap. A decent dual band, 8 watt Baofeng can be bought off Amazon for under $30. The range is not great. You can get ten to twenty miles in a flat, fairly low population area. In a big city, you would be lucky to get even a few miles. With repeaters, you can extend your range significantly. HAMs are authorized to transmit up to 1,500 watts on many bands though, and at least 200 watts on the majority. That's enough to communicate with people several states away, and under the right conditions, it is enough to communicate around the world. Even 200 watt transmitting hardware is pretty expensive though. Most HAMs spend most of their time under 100 watts, even if they do have equipment capable of far more. (In fact, one of the legal restrictions for HAM radio is that you only use as much power as necessary for your current purpose. If you are hoping to reach stations around the world, that completely justifies 1,500 watts or whatever the maximum for the particular band is, but for regular short to medium range communication 100 watts is generally plenty). Adafruit's microcontrollers, on the other hand, transmit mainly in the millwatts range. They are designed for very short range communication, not for HAM level communication. They use unlicensed bands restricted to very low output power, but those unlicensed bands often overlap with HAM bands, where licensed operators can transmit with much higher power. For example Adafruit's Radio Featherwing 900MHz (not a sponsor) can transmit at 868 or 915 MHz. 915 MHz is right in the middle of the 33cm HAM band, which allows transmission up to 1,500 watts (I cannot find anything saying there is a lower restriction on this band, and the default is 1.5kHz) or 10 watts for spread spectrum (which may be necessary around industrial, medical, and scientific complexes that radiate on this band). To do this though, you will need an amplifier, and decent amplifiers are hard to find, especially when looking for 5v ones that can run off the same USB power as the device itself. Adafruit also has offerings that operate at 433 MHz, which is in the middle of 70 cm HAM band, but again, while we can legally transmit up to 1.5 kW, amplifying the output requires devices that are just hard to find commercially, especially in the context of small, low cost projects. In addition, these are just two bands, and very narrow parts of them on top of that. 915 MHz is great, unless hundreds of HAM licensed makers are all trying to use the exact same channel or narrow range of channels at the same time. (I am actually not sure if "868 or 915 MHz" means a few channels around those or only those exact frequencies, because if it is the second, that is lame and makes these practically useless for HAM, because if more than a few people are transmitting at even a few watts at a time within a few miles, the interference will just ruin the whole thing.)
What do HAMs need for this technology to be useful to them?
First, we need hardware that can be tuned to a range of frequencies within the desired bands. If that 915 MHz and the 433 MHz are single monolithic frequencies that the devices can transmit on, as I said before, they are practically useless for HAM applications. At their default power, the potential for cross talk is limited to operating mostly in the same building or maybe one building over. For unlicensed use, this might be reasonable. For HAMs, we are looking at transmitting at at least 5 watts at the absolute minimum. That will cover an entire neighborhood and the next one over, at the absolute minimum. Under the best conditions, we are talking miles. Even in a moderate sized town, there are likely to be enough HAMs for that to be a serious problem.
Second, we really need low voltage amplifiers. I mean 5 volts. Adafruit's microcontrollers almost entirely run off of USB power. Requiring an additional 12 volt power supply for a 5 to 10 watt RF amp is just plain unreasonable, especially for small devices designed to accommodate mobile applications. Ideally these devices should be able to run off of USB "phone charger" batteries. In fact, some Adafruit devices run off of 3.3v lithium batteries, so it might be even better if they can run off of 3.3v and have a regulator onboard to allow 5v input just like the Adafruit boards that use 3.3v internally. Now sure, I know that this is a tall order. There's a reason you cannot find 5 watt RF amps that run off 5 volts. Voltage is the critical part of RF amplification, because the voltage is what essentially forces the current out of the antenna. It's very likely that RF amplifier ICs do not support less than 12v for 5 watt output. In theory it should be possible to design and fabricate ICs that do support this, but companies like Adafruit are not in the IC development game, so it is probably not reasonable to ask them to do this. They might be able to find such a chip if it already exists though. They are quite good at that! And 10 watts at 5 volts is probably even less reasonable. But, there is a solution that companies like Adafruit can manage. While they do not do their own ICs, their bread and butter is doing PCBs, and a PCB could easily be made that integrates a 12v 5 watt or 10 watt RF amp with a 5v to 12v boost converter. Now, of course this will reduce efficiency, and it will take a considerable amount of current at 5v. That's a given, but it will at least provide some good medium range power output options for licensed HAMs, that will work directly with Adafruit's other hardware. Imagine a 5 watt 5v RF amp with a U.FL cable that can be connected to the Adafruit Feather RP2040 RFM69 Packet Radio. Now you have a very HAM friendly option. If Adafruit wants to avoid selling things to people who are not authorized to use them, they can require purchasers to have an Adafruit account, and they can request and verify the buyer's HAM call sign to make sure they are legally licensed. I am totally willing to give Adafruit my call sign, so that they can verify that I am legally allowed to use what I am buying, and I am sure most HAMs are. I am not certain how this would work for buyers outside of the U.S., but if their countries have online registries where you can look up someone by their call sign, the same mechanic could be used. And because Adafruit specializes in hobby volume production, they would be ideal for serving a smaller hobby market (which frankly is a lot of what they already do). Of course, Adafruit is just one example. Sparkfun could do this as well, as they have a similar business model as well as products in the same domain. I especially like the idea of something like the above RP2040 packet radio though because it has a built in U.FL port for an antenna or RF amp and a STEMMA port for simple interface with other peripherals. It also has plenty of GPIO pins on top of that.
Third, we need tunable modular filters. Many devices can produce RF signals with PWM, but PWM is incredibly dirty. PWM is a sort of phase modulated square wave signal, and square waves are composed of infinite harmonics. This means that a signal generated using PWM will interfere with an enormous number of other frequencies, which is illegal. Radio in general, but definitely HAMs, have regulations requiring such spurious signals to be kept below certain thresholds, to avoid harmful interference both within and outside of the band being transmitted on. A great example is the Raspberry Pi. At least from Pi 2 onward, PWM can be used to generate signals from 5KHz to 1,500 MHz. That covers the vast majority of the practical HAM bands. The problem, as mentioned before, is that PWM is incredibly dirty in terms of signal purity. To legally transmit with a Raspberry Pi using PWM to generate the signal, it is necessary to have a very good filter between the Pi and the RF amplifier, to filter out all of the undesired harmonics. But, you cannot just have a filter for say, the 70 cm band. I have not looked at the frequency output range for a Pi being used this way, but I would guess that there are also some spurious emissions in the transmission band, so the filter would likely need to be narrow and tunable, to filter out spurious emissions on frequencies near the transmission frequency. (It is possible I'm wrong here. Square waves generally only contain higher frequencies than the base frequency, so there may not actually be spurious emissions in the HAM bands below the PWM frequency. That said, because the duty cycle is changing to generate the RF signal and does not change with infinite precision, it is likely that there is some within or very near the transmission band. Maybe a manually tunable filter that is narrower than the band could be used, allowing the user to tune it to the desired portion of the band, while being narrow enough to filter out any nearby harmonics.) Anyhow, what it comes down to is that for microcontrollers with PWM, it is possible to generate RF signals without needing any radio at all, and this is generally more flexible than a dedicated radio IC, which typically only transmits in a very narrow range, but a fairly good filter is required. These are not terribly difficult to build if you have the right equipment for very precisely measuring capacitance and impedance, but if companies like Adafruit sold high quality RF filter ICs, that would really help the HAM community. And if they had some very narrow band I2C tunable versions, that would be even better. It would not make building radios entirely from scratch much easier, but it would definitely make it feasible within existing FCC regulations, and it would significantly reduce the need for expensive analysis hardware that is normally required to make sure your hardware adheres to regulations.
I think this is important and valuable. The 1990s and 2000s were not a great time for HAM radio, but we have pushed through that, and modern technology is better than ever before for HAM. Licenses are much easier to get now, with the removal of the Morse code requirement. Even just a Technician license (the lowest level available) grants permission to use the cheapest bands to operate on (the HF bands are heavily restricted for Technicians, but they require very large antennas that can be very expensive to install). In addition, all of the VHF and higher frequency bands available to Technicians allow Technicians to transmit data, making them ideal for technological applications. Companies like Adafruit could really help the HAM community by putting some resources into creating products lines exclusively intended for HAM, but they could also help revive HAM radio and make it interesting for younger people by bringing it into the realm of modern hobby technology. HAM was once cutting edge radio technology. It lost that because companies supporting that disappeared. Companies devoted to serving makers and hobbyists not only have a perfect market just waiting for someone to serve it, they also have an opportunity to turn HAM into a much bigger and more interesting hobby.
I personally became a HAM radio operator because I was interested in the technology. I am far less interested in the personal communication aspect of the hobby. I recently got my Amateur Extra license, and shortly after that I got my first radio. I got my General license in 2010 (I skipped Technician, passing the Technician and General tests in a single sitting), and it took me over 10 years just to get my first radio, largely because my primary interest was in the technology and less in the personal communication, and no one was serving the market I represent. Sadly they still are not, but 13 years later there are a lot more people like me, who are interested in HAM for the technology (including a surprising number of older HAMs, like the one who taught the Technician licensing course I recently attended with some of my children), but who have little motivation to get involved, because the technology is just is not available. It does exist, but even companies who claim to be devoted to serving the maker market are failing to serving the original makers.
I want to see HAM radio return and take its place at the head of the maker movement. Old people are not just washed up has-beens. They are troves of valuable knowledge. HAM radio itself could evolve into far more than just radio. I want to go to HAM club meetings and talk about programming radio enabled microcontrollers. I want to go to HAM meetings and talk about using radio communications for more than just talking to each other, accessing very limited portions of the internet, or gathering weather telemetry. HAM clubs should be learning about adding RF technology to your home and your appliances, so that you can control them remotely. But when the majority of HAM technology is handheld radios that are only good for talking to people you seem to have little in common with, it frankly sounds and is kind of boring.
So I guess this is my challenge to Adafruit, Sparkfun, and anyone else to claims to be dedicated to serving the maker community: Don't forget the HAMs. Start producing products designed for them. Start using whatever learning platforms you have to encourage makers to get their HAM radio licenses and start learning to use more advanced radio technologies. You can turn HAM radio into the hobby it was always intended to be. All you need to do is serve the original maker community as well as you serve the rest, and we can bring them together as an incredible power for the development and progress of not only radio technology but also the broader maker movement and technology in general. HAM should not just be about radio. It should also be about applications. If we do not have the appropriate hardware though, we cannot build applications around HAM radio. Please, please fix this problem.
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