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FT8 – Tipping Point for Ham Radio? (flexradio.com)
158 points by lightlyused on Oct 19, 2018 | hide | past | favorite | 113 comments



This has one unspoken bonus feature: Not having to talk to an octogenarian about politics.

I know it sounds silly, but I suspect this is one of the huge features driving it's success. Amateur radio is plagued by bad actors and grumpy old men, along with the general age imbalance that makes it fairly unpleasant for young people and extremely unpleasant for anyone who sounds vaguely feminine...


As someone who went from nothing -> Amateur Extra when i was 23 (25 now) from a random spurt of inspiration to learn ham radio and then promptly did nothing with the license i agree with this.

I don't know exactly what i was expecting from getting the license but i will say that i didn't expect it to basically just be dominated by old conservative men who don't appreciate younger folk stepping in on their air space. I have yet to actually speak to anyone because i don't feel like there is anything i would want to say.

Part of me was excited to do things like decode ISS transmission or send digital packets around the world; but i wanted to ease into the higher cost HF equipment with a simple and cheap as chips baofeng UHF/VHF radio (i know, its garbage but i like i said i wanted to ease into the hobby) and when i discovered there was nothing to do but listen to old men rant i just shelved the radio.

I considered getting the bitX40 but never ended up doing it because i don't own the house i rent and putting an antenna up seems like a lot of work for a place i might move from soon. Admittedly maybe my problem was getting a baofeng UHF/VHF instead of something that i can plug into my computer and do digital modes with. But no one was really around to help me decide what to choose or give me insight into what i may want to do with my new AE powers.


Guys, no one is forcing you to listen to that stuff. Get off the voice bands, get on digital and you'll have a blast.

Here's a fun talk at Defcon from Balint Seeber, a ham who focuses on security, to get you in the right headspace. I attended this and the group of 6 of us that hung out afterwards with Balint was some of the most impressive people I've met at Defcon. One had built a bug sniffer. Another was intercepting satellite comms over Iraq. And Balint had a prototype SDR board he shared with us. So much fun.

https://youtu.be/cHtHBqSZE4k

Yes, there is a community of rag chewers who use the voice bands, especially lower HF, to keep in touch with friends. That's a tiny part of the hobby and community.


Exactly this.

Too many people get funneled into this trap by the ARRL who understandably push "get on the air today!" type articles which haven't been updated since the 80's and have people getting HF radios and hunting for repeaters on the 2M band. And the grumpy old guys who are pissed off it isn't the 80's (or 70's or 50's, few seem to be nostalgic for the 60's) anymore.

In the digital radio space its a lot more open, and just being able to work with radio has become pretty easy these days. I've got a bunch of SDRs now, and I agree the ADALM-PLUTO ($100) is the most cost effective way to get a nice xmit and receive SDR. The RSP2 from SDRPlay is another one that is good for the low bands through 2G (its like $200) then the next step up is the HackRF-1 ($300) or LimeSDR ($300) or LimeSDR Mini ($170). Above that you start getting into the Ettus/National USRP radios ($3000 and up).

Small WHSPR (whisper) radios like the article mentions are inexpensive to build and fun to play with as well, not a lot of chatting but tagging beacons and getting tagged. Or putting lightweight radios in a balloon and flying it around the world (https://www.mchsarc.com/?page_id=13)


Those grumpy guys pervade the web too, in some places when I talk about OpenWRT I'll get mobbed by people that view it as evil, linking it to dead forks of the early 2000s that were popular for blasting RF. These same people love to hate on the GPL, over squabbles that happened decades ago. Highlighting that GPLv3 fixes the permanent license revocation loophole of GPLv2 goes in one ear and out another with 'em.

When I point out the dozens of watts some HAMs are blasting in part of the 5Ghz band, these same asshats are all over that shit. It makes me want to have zero involvement with this toxic community, since many active members can't handle basic logic.

For now I'll stick to the ISM bands, Part 15 is good for many applications.


I've searched this space looking for a decent RX/TX SDR that does a few watts. It's surprisingly hard. Seems like the 5 watt $30 HTs (that are SDR based) are extremely common, but as soon as you add any flexibility it's $1000s.


Those two constraints are easily separated. Radio and separate power amplifier. You will find that a really wide band power amp is expensive so a lot of people will have two to five PAs and an RF switch to select between them



I love the digital stuff, definitely an awesome space.

Another great group is Summits On The Air[1] which basically involves hauling a radio up to the highest peaks and seeing how many people you can contact from the top of the mountain.

It's something you can do with just a simple 5w VHF handheld(yay line-of-sight) and the group is really welcoming. Last weekend I was up at about 6k ft and making direct line of sight contacts over 100mi away on 5 watts.

[1] https://sota.org.uk/


Oooh that's a tough one. I haven't been in the market for a while, but even used gear like the Kenwood TS2000 which is now about 18 years old is still pricey. And a Yaesu FT817ND which is a low power HF radio comes in at around 800 bucks.

I really would like to hear from others, but I would look at getting an SDR that can handle HF frequencies down to at least 7Mhz if you want to have some serious DX fun.

I have a HackRF One, but it retails still at around $300 bucks. I have a feeling if you use the google and shop around, you may find a SDR and converter combo that'll get you down to 7Mhz with low power.

Then building your own antenna is trivial. Because you're using very low power, you can actually build a dipole antenna that doesn't even need a balun. I've used stealth antenna wire which is super slinky and nice to work with to create a low power antenna (in ham speak, we call low power 'QRP'). It's basically just coax that splits the core and shield into left and right branches. You use the stealth wire for the branches and you calculate the length based on frequency. So it's locked to a specific frequency like the 7Mhz band. But they're super effective as long as you string them in a tree. The whole kit can be bundled up into a backpack, taken for a hike and when you get to your destination, have a picnic, string up the antenna in a tree and make a few DX (long distance) QRP (low power) contacts on your laptop. Yeah, it's a geeky hobby. [insert joke about preparing for the end times]

But again, I'd love to hear from other hams on here re developments in low power low cost HF SDRs.


I use the RS-HFIQ, a 5 watt 80-10 meter SDR transceiver[1]. If you don't want to mess with sound card configuration you can add the Pi SDR[2] which adds an Orange Pi and sound card to give you an ethernet-connected radio.

[1] - https://hobbypcb.com/rs-hfiq [2] - https://www.pi-sdr.net/pi-sdr/index.php/pi-sdr-projects/pi-s...


So what lower-cost radio do you recommend to get started on non-voice bands? I see the bitX40 people made a new model called the µBITX. What bands and protocols will that open me up to? I also looked at the RTL-SDR but thats receive only and i'd like to do some transmitting and explore my options. Basically just looking for a cheap option that lets me explore the most bands/protocols.


I'm not parent/GP...

I bought a ADALM-PLUTO from Arrow. $98 shipped. It's a SDR that goes from 325MHz-3.8GHz, and with a "hack" will go from 70 MHz to 6GHz. 7dBm (or 5 mW Tx).

You'll need amplifiers to go from 5mW to QRP (~1W). I did find one on Banggood for 1MHz-1GHz with up to 35dBm gain. I'll still need one for 2.4GHz and 5.8GHz, but that's a small price to pay for having nearly 6GHz of spectrum to read. ( https://www.banggood.com/1MHz-1000MHZ-35DB-3W-HF-VHF-UHF-FM-... )


I also have an amateur license. How much is the cost to go to non voice band for starters??


I'm not entirely sure I can competently answer that.

I know with my ADALM-PLUTO hardware, it can receive from 70MHz to 6GHz, but at only 5mW. So if you want to start Tx-ing, you'll need a low noise amplifier for the band you want to transmit. Also, the antennas are for 325MHz-3.8GHz and are anemic stubby 1dBi. You will want better antennas. Ideally, for the respective bands you want to do stuff with.

I'm still piecing my software together. Right now in open-source land, there's lots of individual decoders and some encoders. I'm having good luck with SDRangel for handling Tx as well - there's some weirdness with encoding data for Tx with the plugins. But that's just growing pains of this being new.

The other problem you'll have, if you just don't pony up kilobucks for "ham radio hardware", is that going from 7dBm (5mW) to 30dBm (1w) is going to be weirdly expensive. And then that only gets you to 'QRP'. You'll then need a second stage amp to go from 1w to higher power.

If you do EME digital modes, you're amping up from 5mW to 1.5KW . $$$$$$$$ lies here. But I'm sure if you talk in freenode IRC in ##hamradio , there are EME hams there.

So to better answer your question, rather than give you a bunch of options, here's a general idea of cost breakdown:

Cost = laptop + ADALM-PLUTO (or relevant SDR for HF) + 30 dBi amplifier for band you want + antennas for band you want

My laptop is $500 and is Dell precision m4800. 4 cores/8 threads, 32GB ram. $500 from ebay. ADALM-PLUTO is $98 shipped from Arrow. I bought 2 1.35GHz-9.5GHz antennas for $13 each from Banggood. I'm looking for a 7dBm->20dBm 2.4GHz amplifier That would bring me up to 100mW output. I also bought a random assortment of SMA connectors for $12

That would leave my current total at $136 for the wireless hardware, or $636 if you want a dedicated laptop. RasPis won't work with SDRangel - it eats CPU for breakfast, lunch, and dinner.

https://www.banggood.com/1_35GHz-9_5GHz-UWB-Ultra-Wideband-L...

https://www.banggood.com/18pcs-1_2G-5_8G-FPV-Telemetry-Anten...


> I have yet to actually speak to anyone because i don't feel like there is anything i would want to say.

A lot of this probably has to do with where you are, or more specifically, where the people you're hearing are. I first got into ham in North Carolina. The people there were talking about hunting and meat preservation techniques.

Then I moved to San Francisco, and later to Seattle. The people in these places are more talking about things like high bandwidth microwave and forming mesh networks, making reliable contacts with man-portable rigs, antenna design, raspberry pi vs adruino, sending video from remote controlled aircraft, and dozens of other things that fascinate me.

It's not an age thing, it's an interest thing. And the types of things people are interested in is strongly correlated to their geographic area.


> Part of me was excited [...] decode ISS transmission [...] cheap as chips baofeng

You can totally do this without spending more money! I've got my first award hanging on my wall for using my cheap as chips Baofeng to do this very thing. The award itself is really cool and has "INTERCOSMOS" across the top in English and Russian, along with an illustration of the Russian ISS module(s). The decoder I used was the free Robot36 app on my Android phone. I believe there is another SSTV event coming up on October 27.

If you don't want to speak to anyone, this kind of activity is awesome. Turn squelch off, TDR off, dial in 145.800 and hold your Baofeng next to your phone running Robot36. You can easily monitor the ham sats and other sats too; heck you can just sit on a park bench and do this really easily. If you want portable sat & ISS tracking, there are apps that do this really well.

Since I got my extra last year, I've volunteered at three events (1 ultramarathon and 2 public safety drills at local hospitals), joined a club I like (TheGuildGlobal.org), and talked to people all over the world. I haven't set up the outdoor antenna for my donated Swan HF rig yet (thanks to some super nice local hams) but Echolink is actually really fun; I didn't believe it until I tried it. And how else can you talk to someone in Japan and someone in Scotland within minutes of each other. I heard the guy in Japan dropping his jaw open when he found out I lived in the same city in Japan where his daughter lives, so you never know. (A day after that I talked with a guy up in Seattle, where I'm originally from, about the Green River Killer for a few minutes. Fun stuff. Haha.)

I haven't had a single old man conversation that I felt I couldn't politely and immediately end. Heck, I've had old timers cut out on me with "welp, I just arrived at my destination, have a nice day, K1ABC clear." It's that simple and normal.

Anyway, I hope you'll give it another chance. Find the stuff you like and build on that. Find people you don't mind talking to, and talk to them. Find nets you like and chime in. There are some really awesome people out there who aren't political and who would love to talk just about anything you see here on HN. I know because I'm one of 'em. Hope to hear you on the air sometime --KM6NHH


I definitely will try to do that SSTV event.

I don't think i "get" echolink. You hook up your radio to your computer (somehow? I don't know how i'd do this with a baofeng) and talk into it and then it uses the internet to send that across the world to other peoples radios who are also connected to their computer? It just feels like a discord voice chat with radios as the input/output device. Am i missing something?


It's true, you really have to try Echolink to "get" it. I have heard this many times. IMO its curb appeal is low but it is a lot of fun.

I have it on my phone, and I also have the (Windows) app running in Wine on my Linux desktop. You can just use your built-in mic or a regular sound card mic. I have never even used my HT with it. But you can, if you want.

And that opens up one of the really neat aspects: You can end up talking to someone through their repeater. Just about every time I talk to somebody, they're on their HT out in the field somewhere and they have no idea that I just came in through Echolink. You might catch someone who's out on a hike, and get some pictures or a video on Twitter later. Or talk to someone in their shop.

There are also nets that you can listen into on Echolink. Check out dodropin.org to get started.

Finally, no non-hams are allowed to register. This is a huge pro if you're comparing with e.g. Skype or Chat Roulette. The sign-up process is pretty legit, a human is reviewing your license. So there's this automatic level of politeness and protocol which is refreshing. On Discord, you just have no idea, especially if you're chatting with random people. On Echolink, their account status is at stake and it's kind of like a big closed group.

Related to this, I like that TheGuildGlobal.org are branching out, not only onto SIP but also to platforms like Zello. The ham world actually brings a high level of discourse to communications, even if you figure in the occasional grump. There is always another mode to try.


If you're just using your handset as a hand mic for what is basically Skype, yeah that's not all that exciting.

As far as I understand, VoIP links for radio primarily adds a tool in the toolbox for expanding & linking repeater networks. Instead of beaming your local repeater over the mountain range to get to the next village, you can link two repeaters over VoIP.


The SSTV stuff was really cool, especially how well it meshed with a cell phone aka pocket computer. There are some real applications too, unfortunately it's kind of techy for ordinary people.


QSX is coming soon. https://www.qrp-labs.com/qsx.html

Just google like any other technology. Answers are all out there. I never went to any amateur radio clubs. I paid up to do my exams, bought a radio and just wobbled into the bar like a drunk.

Also you don’t have to talk to someone past exchanging RST etc. If they start going off on one just tune away.


can you explain how QSX is different from the other SDRs being mentioned (ADALM-PLUTO, HackRF One, etc)? Is it just more transmit power than those other SDRs? I feel like i'm missing something.


It is a SDR-based HF transceiver instead of wide-band SDR. SDR is implementation detail and extra feature. Most SDRs are receive only, and the ones that can transmit, like ones you listed, are limited in power.

The other difference is interface. The QSX, and other SDR-based transceivers, work like other regular transceivers. They have USB port for computer control and sound card output. Some newer radios provide I-Q input and output which can be used for more advanced modes. But the bandwidth is limited compared to the SDRs which can monitor an entire band.


So would you recommend the QSX as a good way for a beginner to get to explore all the different bands/modes? Do you think this is a good replacement to - say - a hackRF? Or is the hackRF better for specific use cases like debugging because it has wide bandwidth?


When you're doing RF stuff you're usually really only interested in single signal reception and usability. To learn about the various modes this will be way better than an SDR.

The SDR sure has utility but that comes at a compromise. I've done some professional RF stuff in the past and 99% of the problems are solved with very simple and way more precise gear compared to an SDR.

Have a look at http://websdr.org and have a play around with SDRs and then go look at a video for a Yaesu or Icom "rig" and see the difference in the usability. The QSX is more the Yaesu or Icom end of things.


Well i'm sold, can't wait for the QSX to be released so I can really start using my AE license! Thanks!


Before you do, if you have money available to throw at it, I'd probably go for a commercial rig first that can kick out 100W and start there. Yaesu FT-450D is the sort of thing that's a decent "first rig".

If you can't afford it, go for the QSX! I may replace my commercial rig with one if it's any good.


One's a transceiver. One's an SDR. The first is way more human oriented and focused on utility.


> I have yet to actually speak to anyone because i don't feel like there is anything i would want to say.

That's true for many people. You don't need to use it to make a statement or to express your individuality, you can just participate in contests, enjoy propagation, etc.


Yes, but if you don't have anything to say and you don't want to hear the things other people are saying, then what are you doing? Thus the remark that the radio was shelved.


DX and contesting is still a sport and for these people many contacts end after QRZ and signal report


In certain places like 80 meters it has always been this way. There was a rather famous individual on 80M AM that used to call CQ by saying no lids, no kids, no space cadets. A lot of young ham in the sixties like to really get in this old boys face. I wasn't one of them and found out he was a pretty intelligent fellow, he just didn't had a low tolerance for fools.



Sounds kind of like the mirror opposite of HN


I feel the need to clarify AWildC182's comment because I think it reflects poorly on amateur radio as an inviting place for younger people.

There are some "scenes" in amateur radio that are dominated by older, somewhat conservative leaning discourse. Some VHF and UHF repeaters are like this, and there are many groups of people who chat with the same group every night on 80m SSB.

Some newcomers start out on VHF/UHF repeaters and if they live near one that is like this, it may turn them off to the entire hobby even though it's just a small part of it.

I recommend CW and FT8 as less conversational ways of getting on the air. If you are in the mood for a conversation, you can do so on CW, and there are conversational digital modes.

I personally like contests and experiencing propagation and band openings, but don't really need to have a long chat.

So my recommendation for a new licensee would be to jump right into MSK144 and then determine what to do next :)


The general responses to suggest getting off of voice modes either HF or VHF, and into digital or contesting has problems for people not living in a large city with multiple clubs to choose from. I’ve been an active ham for more than half of my life now and been finding the toxic culture in local ham club is frustrating, and real problem to recruiting younger people to the hobby.

I used to participate in the local club but quit after a few too many times hearing racist comments from the (not-octogenarian) club president with no reaction by other members, I decided to call it quits. That also means the tools and instruments I used to be able to borrow, or having a few extra sets of hands to help put up an antenna has gone away. And I won’t recommend the club to other people who have asked about getting into the hobby, at least not without telling them what to expect.

I still have a fellow ham I talk with who is a non-club member in the area, but he’s been in and out of the hobby as well for the last few years.

Sure this is one datapoint, but the value of having a local club with available knowledge, and tool and junk boxes to raid makes it a lot easier to stay active in the hobby.


> dominated by older, somewhat conservative leaning discourse

You put it in the very kindest light. It is often simply appalling.

> I recommend CW and FT8 as less conversational ways of getting on the air.

Yes. I do slow speed CW a couple of nights a week, just as a way to relax. I can't speak to FT8 but CW people tend to pride themselves on manners.

Learning the code is a question of downloading an app, or listening to a graded set of steps in the car or while walking the dog, for a month. If you can do 5-10 wpm (which just means you recognize the letters, digits, and a few punctuation marks) then you will not have much trouble finding people interested in talking to you. Me, for one.


Some newcomers start out on VHF/UHF repeaters

I'm not close to the hobby but it seems like newcomers are specifically recommended to start out with VHF/UHF voice, equipment being simple & inexpensive, and voice being intuitive.


In my experience, hams break down roughly down into two groups. Yep, there are those who like to ragchew about any/everything. For them radio is a means, not an end.

And then those who are really interested in ham radio itself ... equipment, antennas, modes, propagation ... any of the endless opportunities to explore and trade ideas about new radio experiences with other people.

Those discussions are easiest to have without repeaters or HF QRM. Get to know who's technical in your area (they -do- pop up on repeaters now and then) and those discussions can endlessly fun without the bragging and the B.S.

There are thousands of things to try, and a never-ending range of new technical variations to combine. Possibilities these days are really endless.


I'm a regular on HF and I've found the community to be welcoming and I've learned a lot from people with half a lifetime more experience than I have. Retired doctors, aerospace engineers and other interesting fields. There are many younger contesters who move very quickly and just work to make contacts.

Bad actors? There are a handful, but FCC has taken enforcement action against several. https://www.fcc.gov/general/amateur-radio-service-enforcemen...

Weak signal modes have been around for a while. And voice is a different part of the spectrum.


You're definitely right that there are a lot of really cool people out there. I had a similar experience joining an EAA chapter to discover that a whole bunch of them had worked on Hubble.

That said, the FCC in my experience has been pretty lax about policing the amateur bands. You can go to any online SDR and tune around to find obnoxious, toxic, and illegal behavior within minutes. I've also found that if you're lucky enough to find someone under 50 on the airwaves, there's a >25% chance they're a crazy prepper.


> You can go to any online SDR and tune around to find obnoxious, toxic, and illegal behavior within minutes

Ah, so 4chan for old people.


This...is strangely accurate. Minus the anonymity since some of them will still ID with their callsign which links to a public database with their name and address.


Hilariously true. Nothing worse than hearing “people” on 80m. It’s like a pub night full of racist, sexist old farts. I’m in the UK so this spans Europe as well. It’s not just a US thing.

There’s less trash on 40/20m I find.

I stick to CW, FT8, WSPR. Not enough bandwidth for an opinion :)

On a positive note, nice to see lots of hams in here.


I'm in my 50's and I've been a ham for over 30 years. I understand where you are coming from. I do also operate FT8 and have thought to myself at times how nice it was to be making contacts without having to listen to people ranting.

That said, there are plenty of hams who don't want to complain about politics, we just notice the curmudgeons more. I've had some great HF SSB QSO's lately that never touched on politics.

Some of the more technical modes tend to appeal to hams that are more interested in the technical side than the hams that frequent HF SSB or VHF FM.

There are many bands and many modes. If your VFO lands you on a QSO that you don't want to hear, QSY to another and call CQ.


> Not having to talk to an octogenarian about politics.

Nobody "has" to do this on phone. Of course there are people predisposed to this but you don't have to talk to them or you can change the subject. For instance I still enjoy discussing radio stations and usually it's interesting to hear about someone's elaborate construction and what they are doing with it while they are willing to hear how I am getting over the equator and atlantic with no amplifier and a shitty piece of wire.


I absolutely agree. The topics of discussion on HF are mostly conservative politics, joint replacement surgeries, and their wives' behavior.

Digital modes are a godsend.


My grandmother is a ham that is heavily involved in her ham club. Everyone was older, but polite. Of course they have different political views, but they're not a bunch of creeps, although there are some weird hams for sure. I knew one guy in college that was getting a license so the government couldn't listen to him like they could for his phone. I was like "what...you do realize you're basically broadcasting out to the whole city".


It is painful where I live on the typical UHF/VHF bands. And even worse if anybody doesn't lie and say they're using a Kenwood/Yaesu/ICOM and instead makes the enormous mistake of mentioning they're working the repeater with a Baofeng.


Interesting. But as a non-ham I find the article chock full of ham jargon which leaves me completely lost.

> What happened to take an esoteric mode designed for multi-hop E skip on VHF and overnight turn it into a worldwide phenomenon across all bands from 2200m through 70cm? In other words, what makes FT8 a killer app?

Indeed. What does make FT8 the killer app? Anyone care to break this down in layman's terms that an EE with basic radio knowledge can understand?


So, multi-hop E-skip is a way that the signal can propagate through the ionosphere. (E-layer skip: https://en.wikipedia.org/wiki/Sporadic_E_propagation). 2200m and 7cm are wavelengths. FT8 is a digital mode that can transmit a very restrictied amount of information -- basically your callsign and where you are. Exchanging this information is enough for a contact, or QSO. The debate is about whether it's still about communication when you can't really talk to people using FT8.

Edit: And contacts are basically how hams keep score. You used to send postcards to the people you'd talked to. Old hams have binders full of them.


Ah, I think I understand. I remember hearing the term, "shooting skip", which I understand as slang CB users used for talking to people past the horizon using the ionosphere to bounce the radio waves.

So if I understand correctly this is a game hams play where you try to skip your signal as far as possible and see if you get a ping?

If I am understand this properly, this successful exchange earns you a point and the old timers used post cards as score keeping, as once the ping was established they could each mail each other.

I assume FT8 is text only?


FT8 and other weak signal modes can work with more noise and less signal than conventional modes. Which makes possible to communicate with the current poor HF propagation, or with lower power devices and longer distances. It does this by using low bandwidth (50 Hz), low bit rate (6 bit/s), and error correction.

The other special thing about FT8 is that it only does contacts, with binary messages for doing the exchange.


> FT8 and other weak signal modes can work with more noise and less signal than conventional modes

I'm a little surprised that FT8 is better S/N than conventional mode of morse code, but then I didn't think in terms of S/N back when I was active in the 70s/80s (btw: Straight key! I finally build a keyer after 5 years of straight key, and then went off to college and didn't have another QSO for many years. :(

Edit: Regard QSO, Do folks even use Q signals anymore?


These low bandwidth / low power modes are mathemagic, extracting signals that are well below the noise floor. Redundancy, forward error correction, and low baud rates are the key.

In morse, the baud rate is low, but you get one chance at each symbol and that is it. With these new modes a small set of bits is sent in a highly redundant fashion such that you can recover the whole message even if you capture only, say, 30% of the bits, not necessarily contiguous.


morse CW is pretty bad in terms of BER because it's hard to create a robust automatic decoder, not to mention OOK (which is morse essentially is for this purpose) is very poor against multipath interference.


The FT8 developers have an amazingly strong knowledge of information theory as well as the many practical considerations of communication over an RF channel. Feature addition and bug fixing are slow because the developers don't believe in abstraction, and instead code as if the only option were a direct carryover of FORTRAN 77 conventions into C++. There's no longer a public repo but https://sourceforge.net/p/wsjt/wsjtx/ci/master/tree/mainwind... is representative of current code.


I've yet to use FT8, but it's wonderful seeing the ham community invest in newer protocols that incorporate things like forward error correction!

Many of the popular protocols, like PSK31 and AX.25 are getting long in the tooth. There's a beauty to their simplicity, but it leaves much to be desired.

Though SDR is a bit of a misnomer, extracting data out of an audio signal with DSP on commodity hardware is becoming the new way to do radio. It certainly will never replace analog voice in terms of simplicity and availability, but it's definitely breathing life into the hobby!


“Is FT8 damaging amateur radio?”

It seems to be achieving the goal of global communications while making better use of limited spectrum to do so. I can't see that as being damaging as it really is an advancement in the state-of-the-art.


Exactly so, and moreover, during a solar minimum, when HF propagation is sub-par even in OK conditions. The weak-signal stuff is what got me interested in upgrading from tech to general, and then extra. Every new thing over the decades has been met with the same "this is killing ham radio" response.


I was listening to some CW last night on 40m while working on compiling WSJT-X 2.0. What struck me is that of the several QSOs they were slow enough for me to follow in my head, the total exchange of information was about the same as with an FT-8 contact. Oh, there were the “filler” items like name and QTH and “73 73 es CUL” and human error corrections, but the information payload in the CW QSOs was not significantly higher than an FT-8 QSO.

The typical CW QSO took about 5-10 minutes to complete. The FT-8 QSO (with essentially the same data payload) took one minute. If anything, FT-8 represents a more efficient way of exchanging information than CW. It’s doubtful the “death” of ham radio will cone about at the bits of a more efficient mode than CW.


JT65 is amazing for weak signals. So this is quite exciting. More data on the specs: https://en.m.wikipedia.org/wiki/WSJT_(amateur_radio_software...


I feel like I'm missing some context here; why is FT8 controversial in the first place?


Global communication in amateur radio was previously only been possible using high power transmissions (which requires a full license).

FT8 makes global communication achievable for beginner amateur radio folk.

Some amateur radio practitioners think if you want global communications without learning radio theory, use your ISP or SIM provider.


But knowing “radio theory” isn’t enough to have global SSB conversations on HF. You need a high antenna and reasonably high power, something which most of the population will never be able to have because of how harshly antennas are judged by others in the real estate market.


Ham radio is an incredibly large hobby much like model railroading or warhammer40K or photography or RC aircraft or sex or ... computer programming.

Similar to every other area of human activity thats ever existed and ever will, tiny sub-group Z will always trash talk everyone doing sub-group A thru Y as not enjoying the model railroading hobby the 'correct' way or not using the 'correct' editor/IDE or not doing the correct thing in the bedroom or whatevs.

So its discussing the usual collision of "whoa this new activity (fad?) is becoming super popular outta no where" with the usual "What I've been doing for 50 years is the only correct way to do it"

There's nothing inherently wrong or bad or incorrect about SSB analog voice modulation on wavelengths near 80 meters; but you can't expect life long aficionados of that particular sub-group to be excited about some rapidly growing subgroup they're not interested in. So thats the "FT8 is killing ham radio"

Now as for why any of this matters, the analog HF SSB crowd has cornered the national USA hobby club such that QST magazine etc promotes 80M SSB operation in the USA as being the "only real ham radio" and then the usual political fallout and drama.


I'd just like someone to de-jargonize the whole article.


But wait. What it actually is? Modulation? Radio? I just didn't get it from the article, so please explain (explanatory article is ok too).


Isochronous Twitter for ham radio except only 13 characters.

It's great!


Low bitrate modulation of short messages. The messages are signal reports, and a whole two-way contact is literally automated multi-message back-and-forth.


digital messages encoded in a format then transmitted using frequency shift keying for the data to audio. it has 15 sec transmit/receive cycles and due to the error correction involved has very few characters that are actually transmitted.


As someone about to start working HF after a long time with a technician license I didn't use I think low power digital modes are a valuable addition. But there is something to be said for PSK31's conversational nature.


There's a variation of FT8, JS8CALL, that allows for text chat and data transmission.

http://js8call.com

Seems to me that, especially for EmComm, this could be a total game changer. Field radio with small antennas, low power requirements, and nearly worldwide reach.


I feel like in an emergency situation, voice would still be the preferred mode since ARES and other HF radio organizations are dispatched to fill in coverage gaps that would have been there otherwise. You also need a working computer with the latest software, a digital interface, and have practiced digital mode operating skills.


In an emergency situation I'll probably have my cell phone, too. What I'd love to have is an app (or packaged web app using WebAudio) that encodes/decodes PSK31 so I can plug in an audio cable from my iPhone to my Baofeng and start typing.


I agree. So, why not a JS8CALL app?

As I understand it, the real go-to mode for EmComm is still CW. Which implies very experienced operators. At some point in the future, you'll have more operators experienced with digital modes than Morse code. So...


A CW app should also be doable....


DroidPSK works great, along with many other apps for other modes; android only AFAIK.


An embedded processor should have the horsepower for the mode. Kit idea?


I think the FCC should remove the 300 baud limit for HF which is super arbitrary and limiting for real digital modes. That limit makes modes that are quite distant from modern day commercial digital modulations viable--FT8, JT65, and so on being examples.

They are primarily asynchronous MFSK detectors with tons of symbols--pretty weird design and a work around of the 300 baud limit. We can't get cool stuff like QAM, high rate PSK, and other nice modes working because of this arbitrary old rule.


Curious, what about the symbol rate limit limits you from using, say 8PSK or 16QAM? Is it that it also effectively limits channel bandwidth to something that isn't practical to transmit and/or receive with higher order modulation?


Super late but good question. I should ask some seasoned hams about this. I'm curious as well.


I've got my technicians license, and have no idea what he's talking about. Can someone explain? Even the AARL page on this that's the top google hit doesn't jargon check itself at all: http://www.arrl.org/news/ft8-mode-is-latest-bright-shiny-obj...


FT8 is a signal encoding mode. My impression is that it is much more robust and therefore also reduces the required skill, luck, etc. in making successful transmissions under unfavorable conditions.

"DX" is an abbreviation for "distance", generally used in the sense of "making long-distance contacts." A "QSO" is a successful contact between stations, and "working" refers to the process of making / attempting to make contacts.

"Multi-hop Es" refers to this atmospheric effect using the E region of the ionosphere: https://en.m.wikipedia.org/wiki/Sporadic_E_propagation

"CW" (for "continuous wave") typically refers to the use of Morse code over a constant frequency wave that's just being turned on and off, which has historically been one of the most robust modes, although it requires skill in encoding/decoding Morse by hand.

"73" means "best regards" or similar; it's from very old telegraphy abbreviations.


Thank you so much!


What you're looking for to research is WSJT - https://en.wikipedia.org/wiki/WSJT_%28Amateur_radio_software...

In a nutshell, Joe Taylor (K1JT) created a program that features novel modulation schemes that solve a few problems that other modulations didn't, like fast meteor scatter modes, modes that are better for Earth-Moon-Earth communications, and modes that work better in very low-signal scenarios with a lot of signal fading due to the ionosphere.

The result are modes that are very slow - only sending something like 13 characters every 15 seconds for FT8 - but far more reliable than other keyboard modes like PSK31 or Olivia. The mechanization means QSOs are stripped to their bare necessities - callsign, location, signal report, and that's it. It's shifts the idea of a QSO by forcing quick, scripted, nearly automated contacts, which is a very well-received change since a lot of HF ops are only interested in the contact, and not the person.



What would you like explained? I know the tech doesn't cover a lot regarding HF (which this is largely for). Sunspots? Propagation? Digital modes?


What is FT8 and why is it controversial with hams?


It's a digital mode that has impressive ability to hear weak signals. Which means you can have a small, inexpensive radio, a really suboptimal antenna, and still make worldwide contacts.

The basic mode only allows you to make contact, it doesn't allow for discussions or data transfer. It's simply a “I'm here, and I can hear you” mode.

It's controversial because a) to some hams, conversation is the reason to be on the air; and/or b) hams can be opinionated and grumpy, and some feel like if you haven't spent $5k on your radio/built your radio from scratch/exclusively use Morse code/devoted five acres of land to a 200 foot tall tower with a Yagi antenna you aren't doing it right. DX (long-distance communications) is an exclusive club. FT8 makes it a lot less exclusive. There's always resistance to that.


Thanks that makes it more understandable.


I'm trying hard to figure out what these "modes" are. Even after watching a video[0] I'm still not sure what is really going on. Is the whole point just to acknowledge 'pings' from other transmitters? Seems kind of pointless but I assume I'm missing something....

[0]:https://www.youtube.com/watch?v=NzXkIvoqvAY


"Modes" would be much better named as "protocols" (like "Ethernet" or "IP"). Originally it was rudimentary analog protocols: AM, FM, Morse/CW that were decoded with simple circuits where "mode" might have been more appropriate.


While that may be true of this mode what it has evolved into is JS8CALL[0] which allows for something like IRC over HF (freeform chat).

[0]http://js8call.com


I've made exactly one contact with FT8 using a low power radio and crappy antenna. I played the generated tones from tinny computer speakers to the mic, just messing around. Someone responded! (Probably semi-automatically...)

I thought it was pretty cool that it worked at all, but it doesn't seem like a very exciting mode to pass the time other than maybe to fill the log book and impress all my hypothetical friends.

The resiliency might be useful for emergency communications in some way, but it would have to be a peculiar type of emergency.


Most "modes" like AM/FM and maybe SSB are like physical layer protocols, essentially just modulation schemes. A number of digital modes also maybe fall into this category as well as morse. FT8 is more of an application layer technology. It uses frequency shift key as it's physical layer but also has other abstractions at work like error correction and some session state management. It's not the only mode that could be described this way either, just the most popular right now.


Sort of. The "rules" to establish a contact generally state that you have to exchange some data, but doesn't define "data". Mostly this devolves into a simple piece of data - your grid coordinate is one example. During contests (yes, there are amateur radio contests), a signal report (strength and clarity expressed as 2 digits) would be accepted.

With a low bandwidth mode like this, there is not much possibility of transmitting more than a few bits of data. So a grid square and callsign are about all that will fit.


"Seems kind of pointless"

Its a hobby...


"Zero sunspots but working DX on FT8!" I don't get it. I thought sunspots killed radio communications?


> I thought sunspots killed radio communications?

They can. Sunspots can also greatly enhance radio communications. Outside of amateur radio this effect is rarely appreciated; ordinary radio service users usually only become aware of sunspots when they interfere with communication. Amateurs, however, operate on many different frequencies, and they achieve communication under unusual, rapidly changing conditions. They often use solar activity to their advantage.

The story mentions "10m DX." This is ham speak for the 10 meter or 30 megahertz band (the high end of the 3-30 MHz "high frequency" or HF band, which is extremely low frequency by today's standards) long range (DX; multiple "hop", frequently international) communication. Using traditional modes the 10 meter band is presently "closed" to long distance communication, meaning you get nothing but static when you listen and no one detects your transmissions. The lack of solar activity is the reason the band is closed. When solar activity is high (lots of sunspots) one can use a low cost transceiver, a small antenna and an easily obtained license and reach people thousands of miles away.


DX is a term for a long distance contact. Increased sunspot activity results in increasing ionosphere ionization, resulting in an increase in the refracting power of the ionosphere. Higher refracting power means radio waves can be bent more, resulting in longer distance communication (also, the ionosphere bends lower frequencies better, so you get an increase in the MUF, or Maximum Usable Frequency that will get bent back to the earth.)


Depends on the band and your application. So what the HAM radio operators are doing is bouncing signals off the ionosphere. With more sunspots active, the ionosphere is more electrically charged, making is easier to bounce signals off of.

People have bounced signals off of the ion trails of meteorites, space shuttle reentry, and other absurd stuff :)


Simple explanation, sunspots energize the atmosphere making it easier for lower frequency signals to bounce off the upper atmosphere back down to the ground allowing longer range because you're not horizon limited.


More sunspots are associated with increased solar flux, which cause ionization in the upper atmosphere. HF (3-30MHz) communication is generally enhanced by increased ionization (to a coarse first-order approximation -- the nuances fill many books and are not entirely understood.)

At other frequencies, sunspots may or may not be a good or bad thing, depending on your definition of "good" and "bad".


Is there any way I can pick this up using an RTL-SDR dongle?


Yes. Make sure you are using direct sampling, attach a long wire, string it up. Use an audio pipe to pipe the audio from your SDR software into the WSJT-X software, which also lists the default frequencies for a given mode. Enjoy!


By FT8 do they mean FT8 Call?


FT8Call has been renamed to JS8Call (and also mentioned upthread).


But, what is FT8???? :(


So is FT8 is to ham radio as WebAssembly is to the internet?


From the balance of comments on this article you'd think FT8 was saving ham radio from itself. /death of ham radio predicted, film at 11


It’s been dying for about 30 years I understand. Kenwood, Yaesu and Icom all went bankrupt 20 year ago. Home owners associations stopped all antennas being erected and power lines and ADSL finished the charred smouldering remains off.

Now I’m going to lock myself in the basement with my guns and cans of beans.




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