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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 ack

by esaym 8y ago

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

AWildC182 8y ago
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.
xvf22 8y ago
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 http://js8call.com
jg42 8y ago
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.
Steltek 8y ago
"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.
mcbits 8y ago
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.
VLM 8y ago
"Seems kind of pointless" Its a hobby...

by esaym 8y ago

AWildC182 8y ago

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.

xvf22 8y ago

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 http://js8call.com

jg42 8y ago

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.

Steltek 8y ago

"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.

mcbits 8y ago

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.

VLM 8y ago

"Seems kind of pointless" Its a hobby...