Of old men, digial noise and digital Modes

/ digimode, om, ft8, shortwave, wsjt

Digital modes are the grand-grand-grand children of Morse code, which is called CW in the HAM world. They enable low power transmissions, can be received even through increasing noise levels and are a fun and interesting entrance to the world of worldwide radio communication. But since they also require the use of computers, not every HAM is so happy about them.

Digital Modes give high frequency back to the city dweller

I just started tapping into the wide world of digital modes for Amateur radio. Digital modes enable city dwellers to still enjoy high frequency (HF), which otherwise requires power and antenna lengths not necessarily compatible with neighbors, available space and entertainment electronics. When I used my antenna with enough power to be heard in SSB on the venerable WebSDR in twente, I had my girlfriend complain about hearing my voice on the speakers in the living room. SSB on HF requires antenna that resonate and considerable power output into such an antenna. Combine both with other conductors around like speaker cables around the house you suddenly have more than the intended antenna sending and receiving. This can cause all kinds of trouble and needs to be avoided. That is why using HF in an electrically crowded environment requires finding methods compatible with the needs of its neighbors. Side note: I mitigated the problems in my house via new or shielding existing cables.

The fun stopping electric noise

Electric noise is an increasing problem for people living in cities. VDSL, Powerline modems & cheap Chinese electronics tend to create noise massively affecting radio reception. Not only traditional shortwave feels the pain, but also frequency ranges used by "normal" people not stuck in the last century. Radio controlled garages, baby monitors, WiFi and many other end-user electronics are affected by increasing noise in the urban space. Whenever you cheap out on a transmitting device by buying it online from China, that little power brick, that one cable coming along in the packages has a great chance to be a polluters. Sadly, very few people are aware of this and even fewer care. And of those who care, some are wack-jobs afraid of electronic smog affecting their health. In Germany, every citizen has the right to clean air. Clean of electrical noise, that is. Not many know it, but you can call the authorities in the form of the Bundesnetzagentur to come your location and check the air for electric pollution. All electronic devices sold in shops in Europe have to adhere to the CE-norm, which includes regulations on radio emissions. In practice, the CE norm is useless, since companies can buy the seal. The Bundesnetzagentur can scan the bands and locate polluting transmitters. The measure then taken differ, but it's good to know that this service exists and can be used to either help a HAM to his hobby or stop a rogue HAM from ruining the Tatort for the neighbors. For traditional modes like SSB, AM and older digi modes, the increasing levels of noise on the bands is a problem. But digital modes exists, designed to help out, are there to keep the plagued HAM on the air.

Old men in new times

Morse code could be considered the first digital mode. The signal was either off or on. A binary signal. You can decipher morse just by listening the dashes, no computer is needed. Even today, some countries require HAM's to learn morse code. The idea of being able to transmit and understand morse code without any machine is an attractive one. CW is still very popular on the HAM bands and enables reaching far without too much power. But it's also an old mode, as are its operators. Many HAMs picked up amateur radio when long-distance calls were prohibitively expensive, unreliable, not even talking about international calls. Also nearly forgotten, but there was a time before the Internet, before WhatsApp. Just think of this time for a second: Long-distance is very expensive and with delay, eMail don't exist and Smartphones were Star Trek. Suddenly SSB or CW are amazing ways to reach far. To me this explains the spirit and dedication older HAMs have for their hobby and also for their ways of living their hobby. Many active HAMs are not just called OM, but truly are "old men". For them Amateur Radio is squeezing a microphone and talking to peers directly or sending CW signals across vast distances. I've heard complaints from veterans that squeezing the mic on, not just listening to bands is on the decline. That young people don't speak on the bands that often. If you listen on-the air, there are truly many old men to be heard at any given time of day. And they talk about bad health, antenna, electric noise and maybe a bit more about their antennas. Which is also what many digital modes enable you to do automatically, but I get to that later.

Embrace the struggle with open source

Digital modes require expertise in IT. They also require the ownership of new rigs (that how we call our Transceivers) or auxiliary devices connecting rigs with Computers. While any excuse to get a new part for your rig is welcome, setting up the IT-landscape for proper usage can be challenging. Besides the Hardware to send and receive, one also needs Software to decode, encode, log, locate and upload communications and contacts. Since Amateur Radio embraces and protects open source, quite a few HAMs use Linux as their daily drivers, ideally connected to hardware of their own making. I'd say the wet dream of a hardcore HAM would be a modularized, open source Notebook, running a self-compiled Kernel on a bootstrap Linux, with all software packages self-compiled, connected via self-crimped cabling to a Transceiver, designed by the community, soldered and programmed by the HAM, transmitting via a self-made and tuned antenna, ideally located remotely and connected to the shack via ham net (ham net is, btw, amazing). Writing all of this, I got excited myself. It sounds like a great idea for when I have half a year of free-time and unlimited budget for failed hardware builds. Using Linux as a Desktop operation system, like Windows or MacOS, is a pain. It requires dedication and expertise. Linux for Desktop usage is like walking on a ridge line on top of a beautiful mountain. It's all super great if you walk on the designated and safe path, but if you deviate, you gotta know your shit to save yourself and get back up on the ridge. To those who use and embrace Linux as Desktop daily drivers, bravo. Ironically, these perils make Linux perfect for Hams. Hams have disdain for "Steckdosenfunker", which can translate to appliance users. A Steckdosenfunker doesn't build, he buys. If you haven't soldered and programmed it yourself, you are no true HAM. Just plugging it in, downloading and opening it? Well, why don't you just use Whatsapp on your iPhone or just call the other person. So far, I'm a Steckdosenfunker. I'm not expert enough to build a transmitting device myself nor would I trust my self-made creation enough to allow it direct contact with mains. But that may change. For now I just threw money at the problem and ended up with a couple of plug-and-play solutions to get started. I'm running MacOS. Self-compiling is very limited and the Software packages available to me have agreeable user interfaces. Two things I enjoy over grinding my interest and passion down on kernel modules and package dependencies.

Digi modes


As mentioned before, it appears that many QSOs between Amateur are limited to talking about propagation, antennas, personal health, the general decline of amateur radio, noise and maybe a little more about the antenna. Since you are not allowed to touch on interesting subjects such as religion or politics, intercultural communication is limited to hobby-related topics. I'm only half agreeing to that, but I can also see why no-one wants a 5 Kilowatt proponent of their local dictator on the air all the time, ruining it for everyone else. Digital modes take the mike and repetitive vocal communication and replace it with macros and automation driven by software. You still exchange the same data, you still learn about your setup's performance and modulation quality, maybe about the technical setup of your counterpart, but you don't need to use your voice anymore. From my limited experience so far, digi modes are thus less personal, but content wise comparable.

"Overview" of digi modes

There are many more, one might correctly argue I'm missing the best of the JT modes. These are the ones I've had personal experience with, and that experience is with 14m of wire attached to a tuner on 80m. So take this list with a grain of salt.

Name Power requirement Bandwith Resilience to noise Ragchew Popularity
FT8 Medium to high narrow high no! highest
WSPR Low narrow high no! Ok
PSK31 Low narrow high yes-ish Ok
Olivia Low medium to high high yes not high enough
RTTY high high low yes decreasing

FT8

This mode can be misunderstood as a low power mode. It is not. It is used for situation with bad propagation. Which is nearly always in daytime on 80m or most of the time at night, at least downtown. I learned quickly that this mode is the survival of the fittest. For two hours I was near panicking why no one replies me. I call out into the void and nothing comes back. Surely it must be my rig, my antenna, my antenna tuner, my cabling, my counterpoise etc etc.
But now, I was heard, as I learned clearly the next day thanks to pskreporter.info:

The purple flags mark operators which hear me on FT8

I knew already that my antenna has a slight north western directive, but I didn't know that FT8 operators care for the strongest signals only. Why? It seems that many OM's setup their station for automation. The computer decides which caller to answer. My signal wasn't loud enough for the powers that be, even though I was heard. So this was disheartening.

WSPR

WSPR is boring as fuck. You send out a 2 minute long signal into the world. Then you listen for 2 minutes and send your reception reports to a central web service. Later everyone involved can see on a map, where you were heard and how the quality was. When I say boring as fuck I don't mean its useless. It's the best way to check your system performance with 5 Watts. To learn that you can reach all of Europe and more with 5 Watt from downtown with less than 13m of wire is amazing. But that's all there is to it. That is why many use WSPR for testing and then for automated stations to generate signal reports.

PSK31

PSK31 can be awesome. It's like real-time text chat. The speed of operation is optimized for real-time keyboard input. Even backspaces are transmitted. It is rather narrow band, which means you need less power to reach better distances and power wise it's also not too demanding. PSK31 was the very first thing I tried after licensing. I wanted to see how far my signal carries and really talk to someone, without having to fry my neighbors with SSB. I had 2 good QSOs. But then it dawned on me: While I was frantically typing in fldgi, trying to understand the program fully and overwhelmed with the setup and buttons, other HAMs always replied to me in the same patterns. I'm not talking to humans, I'm talking to machines. Also PSK31 is "pestered" with macro usage. There was a very nice HAM who started typing super slow, on a lesser used frequency with me to give me time and space to get the hang of things. But that was once.

Olivia

I haven't had much experience with Olivia but so far it's my favorite. It's as fast as PSK31, but more resilient. PSK31 transmissions do tend to get chopped up by noise. Olivia is not this way. It requires more bandwidth, but for that it's coming in clear. Like PSK31 it's considered ragchew, a mode for longer QSOs, for real conversations. I'm still on the bands, looking waiting and hoping for good Olivia communications

RTTY

RTTY can be heard almost always on 80m. I feel that a lot of real people are using it, but it's not that much of text chat, more the exchange of reports in a fixed structure. It's more wide band and suffers from degradation with noise. It requires a good amount of power to come far with, so I have not used it for transmissions yet.

Summary


Since I'm a nerd, I like digi modes. The combination of using open source software, radio transmissions and nonthreatening low power to reach like minded people far away is fascinating. All of this autonomously, without the Internet in between. can be on the air without disturbing people around me with speaking in the middle of the night. WSPR and FT8 combined with online service help to quickly learn about propagation and your own setup. I just wish for more rag-chew. I want to talk to other HAMs from other cultures and exchange thoughts, maybe even about recent events in politics. I definitely want to learn more than just my signal report. My interest in Amateur radio might vane if all I end up is hearing 59 and 73, no matter which parameters I change. That is maybe the upside of us "Steckdosenfunker" - we are not pre-occupied with the technical side of things, we might be driven by other motivations to be out there on the air. If I contact a HAM in a country that just held elections or had some other major event, I'd like to know their take on things. Unmediated by a web service, outside of an echo chamber. Digi modes make this easier.

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