During the Symposium in Baltimore last week there was a discussion that I found quite interesting. Billed as a proposal for fairly long-term, future AMSAT HEO possibilities, this blue-sky proposal offers projects that will be fun for myself (and maybe yourself) to learn what's next ... or could be next ...
It seems the cubesat form factor is here to stay for practical launch opportunities available to us ... (please don't ask for getting a phase III-B form factor in this thread!) Wiser people than myself have assured me of this.
Analog SSB and CW modulation in a 3U to 6U cubesat may not be practical at HEO apogee due to antenna size limits on a cubesat and power generation capability of the cubesat limited number of solar cells. Digital techniques were described as a way to make this work.
FreeDV HF Digital Voice for Radio Amateurs was one of the types of technologies mentioned just as an example. I found a demonstration at: http://nicktoday.com/freedv-hf-digital-voice-radio-amateurs/
Interesting, eh? A soundcard interface to your existing radio, sound card in the PC, we're teaching ourselves the first steps into digital radio ... getting ready for the future.
I've only had to interface my soundcard interface to my Yaesu 857D just once. The interface remains stable from a hardware point of view. My PC runs the appropriate software for FUNcube telemetry, SSTV from ISS and prior ARISSat-1, PSK31, JT65, RTTY ... and when I get some time in between preparing the next issue of the Journal I'll add the software for the FreeDV codec.
Perhaps we'll hear more interesting ideas or a fresh approach! At least we could have a thread with some fun discussion ...
-- 73 de JoAnne K9JKM k9jkm@amsat.org AMSAT VP User Services
Point well made, JoAnne.
Now, can AMSAT official support this mode, maybe help/encourage the developers and start to implement it (testing) on for example FO-29? What about a digital mode for the FM satellites? One of the big frustration I have is to decide which one of the digital modes to pick. What is beautiful about this hobby is the diversification which now also becomes the "curse" with promotion and competition of various commercial and open source modes/codecs. Maybe we can help and focus on one "system" for amateur satellite use and get it used/implemented.
Food for thought,
Stefan, VE4NSA
On Tue, Oct 21, 2014 at 4:10 PM, JoAnne Maenpaa k9jkm@comcast.net wrote:
During the Symposium in Baltimore last week there was a discussion that I found quite interesting. Billed as a proposal for fairly long-term, future AMSAT HEO possibilities, this blue-sky proposal offers projects that will be fun for myself (and maybe yourself) to learn what's next ... or could be next ...
It seems the cubesat form factor is here to stay for practical launch opportunities available to us ... (please don't ask for getting a phase III-B form factor in this thread!) Wiser people than myself have assured me of this.
Analog SSB and CW modulation in a 3U to 6U cubesat may not be practical at HEO apogee due to antenna size limits on a cubesat and power generation capability of the cubesat limited number of solar cells. Digital techniques were described as a way to make this work.
FreeDV HF Digital Voice for Radio Amateurs was one of the types of technologies mentioned just as an example. I found a demonstration at: http://nicktoday.com/freedv-hf-digital-voice-radio-amateurs/
Interesting, eh? A soundcard interface to your existing radio, sound card in the PC, we're teaching ourselves the first steps into digital radio ... getting ready for the future.
I've only had to interface my soundcard interface to my Yaesu 857D just once. The interface remains stable from a hardware point of view. My PC runs the appropriate software for FUNcube telemetry, SSTV from ISS and prior ARISSat-1, PSK31, JT65, RTTY ... and when I get some time in between preparing the next issue of the Journal I'll add the software for the FreeDV codec.
Perhaps we'll hear more interesting ideas or a fresh approach! At least we could have a thread with some fun discussion ...
-- 73 de JoAnne K9JKM k9jkm@amsat.org AMSAT VP User Services
Sent via AMSAT-BB@amsat.org. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
Stefan brought up the point ...
... AMSAT official support this mode, maybe help/encourage the developers and start to implement it (testing) on for example FO-29?
The best thing about standards is that there are plenty to choose from!
I'm guessing the only endorsement we'd get on behalf of AMSAT is to find out what works best ... and report back. For phone operation FreeDV seems to be getting a following in the amateur radio world. Perhaps we'll hear on this thread which additional opportunities exist.
FreeDV bandwidth claiming 1/3 the bandwidth of a conventional SSB signal probably won't hurt any of the linear transponders. We don't control FO-29 but suitably equipped stations on each end could probably give it a go ... such as those instances where guys have tried SSTV through a satellite. No special permission was needed. We might need to figure out how FreeDV and Doppler get along together.
We have plenty of time to try this. That HEO proposal is barely more than a verbal proposal and slides from the symposium. It is in that exciting phase where many things are possible and no one can say which way it will go ... or if it will go.
I bet we could have lots of fun with many soundcard modes that fit in a radio's audio bandwidth. FreeDV trying to QSO with a WSJT flavor might not work well however ;-)
-- 73 de JoAnne K9JKM k9jkm@amsat.org
Stefan & JoAnne,
NX9G and W0DHB attempted a FreeDV QSO via FO-29 about a year ago, but I believe they were not able to compensate for Doppler well enough to make it work.
73,
Paul, N8HM
On Tue, Oct 21, 2014 at 9:08 PM, Stefan Wagener wageners@gmail.com wrote:
Point well made, JoAnne.
Now, can AMSAT official support this mode, maybe help/encourage the developers and start to implement it (testing) on for example FO-29? What about a digital mode for the FM satellites? One of the big frustration I have is to decide which one of the digital modes to pick. What is beautiful about this hobby is the diversification which now also becomes the "curse" with promotion and competition of various commercial and open source modes/codecs. Maybe we can help and focus on one "system" for amateur satellite use and get it used/implemented.
Food for thought,
Stefan, VE4NSA
On Tue, Oct 21, 2014 at 4:10 PM, JoAnne Maenpaa k9jkm@comcast.net wrote:
During the Symposium in Baltimore last week there was a discussion that I found quite interesting. Billed as a proposal for fairly long-term, future AMSAT HEO possibilities, this blue-sky proposal offers projects that will be fun for myself (and maybe yourself) to learn what's next ... or could be next ...
It seems the cubesat form factor is here to stay for practical launch opportunities available to us ... (please don't ask for getting a phase III-B form factor in this thread!) Wiser people than myself have assured me of this.
Analog SSB and CW modulation in a 3U to 6U cubesat may not be practical at HEO apogee due to antenna size limits on a cubesat and power generation capability of the cubesat limited number of solar cells. Digital techniques were described as a way to make this work.
FreeDV HF Digital Voice for Radio Amateurs was one of the types of technologies mentioned just as an example. I found a demonstration at: http://nicktoday.com/freedv-hf-digital-voice-radio-amateurs/
Interesting, eh? A soundcard interface to your existing radio, sound card in the PC, we're teaching ourselves the first steps into digital radio ... getting ready for the future.
I've only had to interface my soundcard interface to my Yaesu 857D just once. The interface remains stable from a hardware point of view. My PC runs the appropriate software for FUNcube telemetry, SSTV from ISS and prior ARISSat-1, PSK31, JT65, RTTY ... and when I get some time in between preparing the next issue of the Journal I'll add the software for the FreeDV codec.
Perhaps we'll hear more interesting ideas or a fresh approach! At least we could have a thread with some fun discussion ...
-- 73 de JoAnne K9JKM k9jkm@amsat.org AMSAT VP User Services
Sent via AMSAT-BB@amsat.org. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
Sent via AMSAT-BB@amsat.org. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
participants (3)
-
JoAnne Maenpaa -
Paul Stoetzer -
Stefan Wagener