PSK31 on PSAT-1 (was elbow room)
How about a PSK-31 Cubesat within VHF/UHF?
Because the 6000 Hz and 18,000 Hz of Doppler change on VHF and UHF simply cannot be done with PSK31 that requires tuning accuracy of +/- 1 Hz. By using ten meter uplink and FM downlink we eliminate the downlink Doppler and reduce the nominal Uplink Doppler on ten meters to an average around 1 Hz/sec for the lower portions of most passes. Bob, WB4aPR
Not many of us have a 10m dipole… as part of our satellite setup
A simple portable fishing pole with an 8’ piece of wire on and another 8 foot counterpoise laying on the ground would make a great ten meter vertical for PSAT-1 PSK31 uplink. (Sorry though, that it takes more than 5 watts due to cramming an HF antenna on a 6” cubesat).
Bob, WB4APR
*Sent:* Tuesday, November 03, 2015 10:43 PM *Subject:* Re: [amsat-bb] AO-85 Rudeness (elbow room)
I like to see the 10m uplink "arrow" approach :-)
While PSAT-1 is a nice "proof of concept for PSK-31"
in reality it does nothing for the portable operator and
that is what the original post is all about. ….
Using PSK31 is a great idea, the 10m uplink is the real issue
for the non-use of PSAT-1. Should I say "fatal flaw"?
Not many of us have a 10m dipole ready as part of our satellite setup
(stationary or mobile for that matter).
It is time that we move on and promote digital modes on
frequencies that are actually used within the allocated satellite
bands and even better on higher bands where we have allocations
and we don't use them.
How about a PSK-31 Cubesat within VHF/UHF?
... and leave 10m on the ground where it belongs LOL :-)
------------------------------
On Tue, Nov 3, 2015 at 4:27 PM, Robert Bruninga bruninga@usna.edu wrote:
Take a break from the congestion.... come to the wide open multi-user wideband transponder on PSAT-1. Downlink is good on a handheld arrow on 435.350 MHz FM. It should be able to support dozens of simultaneous full duplex QSO's in the PSK31 waterfall.
Just pick an empty spot and key your TX solid for the full 8 minutes of the pass on your 10 meter PSK31 uplink 28.121 MHz..
To run fullduplex, just run two copies of your favorite PSK31 software. One receiving the FM downlink and the other transmitting on the SSB uplink. Even better is to run Andy K0SM's TX-only uplink client that pre-adjusts for Doppler so everyone can decode you with no adjustments.
Text with everyone all at once.
Bob, WB4aPR _______________________________________________ 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://www.amsat.org/mailman/listinfo/amsat-bb
However,
It would be a great project if we get a 6m allocation from the current WARC meeting. Even if it's only an uplink band (to prevent interference from space to ground) 6m would be usable for PSK. Certainly 2m is now on the point of saturation and all those Uni CubeSats will need somewhere to go.
73
David
-----Original Message----- From: Robert Bruninga bruninga@usna.edu To: amsat-bb amsat-bb@amsat.org Sent: Sat, 7 Nov 2015 3:58 Subject: [amsat-bb] PSK31 on PSAT-1 (was elbow room)
How about a PSK-31 Cubesat within VHF/UHF?
Because the 6000 Hz and 18,000 Hz of Doppler change on VHF and UHF simply cannot be done with PSK31 that requires tuning accuracy of +/- 1 Hz. By using ten meter uplink and FM downlink we eliminate the downlink Doppler and reduce the nominal Uplink Doppler on ten meters to an average around 1 Hz/sec for the lower portions of most passes. Bob, WB4aPR
Not many of us have a 10m dipole… as part of our satellite
setup
A simple portable fishing pole with an 8’ piece of wire on and another 8 foot counterpoise laying on the ground would make a great ten meter vertical for PSAT-1 PSK31 uplink. (Sorry though, that it takes more than 5 watts due to cramming an HF antenna on a 6” cubesat).
Bob, WB4APR
*Sent:* Tuesday, November 03, 2015 10:43 PM *Subject:* Re: [amsat-bb] AO-85 Rudeness (elbow room)
I like to see the 10m uplink "arrow" approach :-)
While PSAT-1
is a nice "proof of concept for PSK-31"
in reality it does nothing for the
portable operator and
that is what the original post is all about. ….
Using PSK31 is a great idea, the 10m uplink is the real issue
for the non-use
of PSAT-1. Should I say "fatal flaw"?
Not many of us have a 10m dipole ready
as part of our satellite setup
(stationary or mobile for that matter).
It is time that we move on and promote digital modes on
frequencies that are
actually used within the allocated satellite
bands and even better on higher
bands where we have allocations
and we don't use them.
How about a PSK-31
Cubesat within VHF/UHF?
... and leave 10m on the ground where it belongs LOL
:-)
------------------------------
On Tue, Nov 3, 2015 at 4:27 PM, Robert Bruninga bruninga@usna.edu wrote:
Take a break from the congestion.... come to the wide open multi-user wideband transponder on PSAT-1. Downlink is good on a handheld arrow on 435.350 MHz FM. It should be able to support dozens of simultaneous full duplex QSO's in the PSK31 waterfall.
Just pick an empty spot and key your TX solid for the full 8 minutes of the pass on your 10 meter PSK31 uplink 28.121 MHz..
To run fullduplex, just run two copies of your favorite PSK31 software. One receiving the FM downlink and the other transmitting on the SSB uplink. Even better is to run Andy K0SM's TX-only uplink client that pre-adjusts for Doppler so everyone can decode you with no adjustments.
Text with everyone all at once.
Bob, WB4aPR _______________________________________________ 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://www.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://www.amsat.org/mailman/listinfo/amsat-bb
On 07-Nov-15 0507, David G0MRF via AMSAT-BB wrote:
It would be a great project if we get a 6m allocation from the current WARC meeting. Even if it's only an uplink band (to prevent interference from space to ground)\
Hi Dave: when we have strong E-Skip, during the season, would there be a mirror up there reflecting Sat-Downlink to my antenna which lies below the E-Skip region?
Hi
Very true Bob and certainly not ideal.
Possibly less of a problem than 29MHz?
I'm just trying to imagine where the next piece of satellite 'real estate' can be found. Most amateur bands are shared and not ideal for satellite comms. Even the ISS has to operate out of band at 2395 to find a clear channel for it's Ham Video transmissions.
I suppose the harsh reality is that the CubeSat revolution has seriously outpaced those who are allocating spectrum.
73
David
-----Original Message----- From: Bob KD7YZ kd7yz@denstarfarm.us To: amsat-bb amsat-bb@amsat.org Sent: Sat, 7 Nov 2015 13:32 Subject: Re: [amsat-bb] PSK31 on PSAT-1 (was elbow room)
On 07-Nov-15 0507, David G0MRF via AMSAT-BB wrote:
It would be a great
project if we get a 6m allocation from the
current WARC meeting. Even if it's
only an uplink band (to prevent
interference from space to ground)\
Hi Dave: when we have strong E-Skip, during the season, would there be a mirror up there reflecting Sat-Downlink to my antenna which lies below the E-Skip region?
participants (3)
-
Bob KD7YZ -
David G0MRF -
Robert Bruninga