PSAT Voltages look good.
The PSK31/SSTV downlink appear to be working well on 435.350+/- Doppler, But you will only see SSTV during daylight passes (Now occuring in the Southern Hemisphere) where the Solar charge voltage is above threshold (6.8 volts. THen you should see SSTV images once every 4 minutes automatically while in the sun.
Northern Hemisphere passes are presently occurring overnight and PSAT2 is in a 28 degree orbit and not seen at all by high northern latitudes and most of Europe :-(
PSAT2 APRS digipeating will remain off indefinately while all these other NEW modes are working. Do not TX any APRS packets on the uplink.
DTMF Grid Uplinks-to-APRS/Voice will be enabled LATER.
While waiting, spend the next day familiarizing yourself with the PSAT2 APRStt touchtone mode. This mode will let you send DTMF Grid square reports which are translated to VOICE and to an APRS packet on the 145.825 downlink. Be sure to prepare your radio with your pre-programmed DTMF grid report IN ADVANCE. And learn how to send Touchtone from your radio's DTMF memory. quickly! It should take under 4 seconds. Do not even think of sending it manually.
Here is WA7MXZ's translator to calculate your onetime DTMF grid report: http://aprs.org/aprs_translator.htm
See how it works in about the middle of the PSAT2 page: http://aprs.org/psat2.html
A successful DTMF uplink will result in a Voice response and an APRS packet on the downlink for display on APRS radios. Again, no APRS Uplink in this mode.
This will be painful because of the 4 second uplink transmissions all colliding on the half-duplex uplink, so PLEASE only attempt your DTMF uplink once every 30 seconds or longer to give others a chance. And of course NOT while PSAT2 is downlinking.
We will advise when this mode is enabled.
Bob, WB4APR
Bob,
Two questions:
What is the SSTV modulation used?
When PSAT2 is transmitting SSTV, is the PSK31 downlink disabled or is the FM audio bandwidth shared between PSK31 and SSTV?
73,
Paul, N8HM
On Tue, Jun 25, 2019 at 6:55 PM Robert Bruninga via AMSAT-BB amsat-bb@amsat.org wrote:
PSAT Voltages look good.
The PSK31/SSTV downlink appear to be working well on 435.350+/- Doppler, But you will only see SSTV during daylight passes (Now occuring in the Southern Hemisphere) where the Solar charge voltage is above threshold (6.8 volts. THen you should see SSTV images once every 4 minutes automatically while in the sun.
Northern Hemisphere passes are presently occurring overnight and PSAT2 is in a 28 degree orbit and not seen at all by high northern latitudes and most of Europe :-(
PSAT2 APRS digipeating will remain off indefinately while all these other NEW modes are working. Do not TX any APRS packets on the uplink.
DTMF Grid Uplinks-to-APRS/Voice will be enabled LATER.
While waiting, spend the next day familiarizing yourself with the PSAT2 APRStt touchtone mode. This mode will let you send DTMF Grid square reports which are translated to VOICE and to an APRS packet on the 145.825 downlink. Be sure to prepare your radio with your pre-programmed DTMF grid report IN ADVANCE. And learn how to send Touchtone from your radio's DTMF memory. quickly! It should take under 4 seconds. Do not even think of sending it manually.
Here is WA7MXZ's translator to calculate your onetime DTMF grid report: http://aprs.org/aprs_translator.htm
See how it works in about the middle of the PSAT2 page: http://aprs.org/psat2.html
A successful DTMF uplink will result in a Voice response and an APRS packet on the downlink for display on APRS radios. Again, no APRS Uplink in this mode.
This will be painful because of the 4 second uplink transmissions all colliding on the half-duplex uplink, so PLEASE only attempt your DTMF uplink once every 30 seconds or longer to give others a chance. And of course NOT while PSAT2 is downlinking.
We will advise when this mode is enabled.
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: https://www.amsat.org/mailman/listinfo/amsat-bb
Audio is shared. I don’t remember the format. Most SSTV programs will adjust. I can look it up later maybe bob
-----Original Message----- From: Paul Stoetzer n8hm@arrl.net Sent: Tuesday, June 25, 2019 6:59 PM To: Robert Bruninga bruninga@usna.edu Cc: amsat bb amsat-bb@amsat.org Subject: Re: [amsat-bb] PSAT2 Future Operations
Bob,
Two questions:
What is the SSTV modulation used?
When PSAT2 is transmitting SSTV, is the PSK31 downlink disabled or is the FM audio bandwidth shared between PSK31 and SSTV?
73,
Paul, N8HM
On Tue, Jun 25, 2019 at 6:55 PM Robert Bruninga via AMSAT-BB amsat-bb@amsat.org wrote:
PSAT Voltages look good.
The PSK31/SSTV downlink appear to be working well on 435.350+/- Doppler, But you will only see SSTV during daylight passes (Now occuring in the Southern Hemisphere) where the Solar charge voltage is above threshold (6.8 volts. THen you should see SSTV images once every 4 minutes automatically while in the sun.
Northern Hemisphere passes are presently occurring overnight and PSAT2 is in a 28 degree orbit and not seen at all by high northern latitudes and most of Europe :-(
PSAT2 APRS digipeating will remain off indefinately while all these other NEW modes are working. Do not TX any APRS packets on the uplink.
DTMF Grid Uplinks-to-APRS/Voice will be enabled LATER.
While waiting, spend the next day familiarizing yourself with the PSAT2 APRStt touchtone mode. This mode will let you send DTMF Grid square reports which are translated to VOICE and to an APRS packet on the 145.825 downlink. Be sure to prepare your radio with your pre-programmed DTMF grid report IN ADVANCE. And learn how to send Touchtone from your radio's DTMF memory. quickly! It should take under 4 seconds. Do not even think of sending it manually.
Here is WA7MXZ's translator to calculate your onetime DTMF grid report: http://aprs.org/aprs_translator.htm
See how it works in about the middle of the PSAT2 page: http://aprs.org/psat2.html
A successful DTMF uplink will result in a Voice response and an APRS packet on the downlink for display on APRS radios. Again, no APRS Uplink in this mode.
This will be painful because of the 4 second uplink transmissions all colliding on the half-duplex uplink, so PLEASE only attempt your DTMF uplink once every 30 seconds or longer to give others a chance. And of course NOT while PSAT2 is downlinking.
We will advise when this mode is enabled.
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: https://www.amsat.org/mailman/listinfo/amsat-bb
Hi Paul,
Thanks for the interest in the PSK31 transponder, as Bob already pointed up, the downlink audio spectrum is shared, so at 280Hz and 374Hz are PSK31 beacon tlm streams from camera board and transponder board respectively. Then every 4 minutes the SSTV signal is present so if you plan experiments in PSK transponder, try to stay between the beacons and SSTV. Description of modes you can find at https://github.com/alpov/PSAT-2/blob/master/README.md
We would be glad to answer any questions about this experiments.
We are still awaiting for any positive confirmation of downlink signal at 435.350MHz as for us it is still below horizon. Any audio recordings, IQ data or at least pictures of reception would be welcomed.
73! Tomas OK2PNQ and Ales OK2ALP
Thank you for the updates!
Regarding the PSK31 uplink, please advise the correct RF frequency.
At http://aprs.org/PSAT2/USER-Operations-Manual.doc, the uplink frequency is listed as 29.401 MHz.
At https://github.com/alpov/PSAT-2/blob/master/README.md, the uplink frequency is listed as 29.48 MHz.
At http://aprs.org/psat2.html, the uplink frequency is listed as 28.120 MHz (in text, w/ a graphic indicating "29.XX?").
Thanks!
-Scott, K4KDR
============================
On Wed, Jun 26, 2019 at 10:20 AM Tomáš Urbanec via AMSAT-BB < amsat-bb@amsat.org> wrote:
Hi Paul,
Thanks for the interest in the PSK31 transponder, as Bob already pointed up, the downlink audio spectrum is shared, so at 280Hz and 374Hz are PSK31 beacon tlm streams from camera board and transponder board respectively. Then every 4 minutes the SSTV signal is present so if you plan experiments in PSK transponder, try to stay between the beacons and SSTV. Description of modes you can find at https://github.com/alpov/PSAT-2/blob/master/README.md
We would be glad to answer any questions about this experiments.
We are still awaiting for any positive confirmation of downlink signal at 435.350MHz as for us it is still below horizon. Any audio recordings, IQ data or at least pictures of reception would be welcomed.
73! Tomas OK2PNQ and Ales OK2ALP
participants (4)
-
Paul Stoetzer -
Robert Bruninga -
Scott -
Tomáš Urbanec