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FT8 – Tipping Point for Ham Radio?

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Re: FT8 – Tipping Point for Ham Radio?

#11

Post by geofft »

tibbon wrote: post #5

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.

Re: FT8 – Tipping Point for Ham Radio?

#12

Post by jquinby »

oakwhiz wrote: post #6

“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.

Re: FT8 – Tipping Point for Ham Radio?

#14

Post by AWildC182 »

esaym wrote: post #9

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

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.

Re: FT8 – Tipping Point for Ham Radio?

#15

Post by xvf22 »

esaym wrote: post #9

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

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

Re: FT8 – Tipping Point for Ham Radio?

#16

Post by kawfey »

tibbon wrote: post #5

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...

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.

Re: FT8 – Tipping Point for Ham Radio?

#17

Post by kawfey »

GlenTheMachine wrote: post #3
wbl wrote: post #2

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.

Re: FT8 – Tipping Point for Ham Radio?

#19

Post by jg42 »

esaym wrote: post #9

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

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.

Re: FT8 – Tipping Point for Ham Radio?

#20

Post by dbcurtis »

jjacobs0 wrote: post #13

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

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".

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