Hi All,
I'am trying to access AO-51 9600Bd packet uplink on 1268.700MHz but had no succes so far. Maybe someone on the amsat bb group has some experience on this? I see on the downlink the message "Frames heard from PACB-1". I think it means the receiver is getting some signal but can't decode it. I believe my 23cm transmitter is working ok with 10w output into 26el yagi. Also the 9600bd is working OK because I can connect to local stations. I see no other traffic on the sat so it seems to me the L band receiver of ao-51 is not to sensitive.
73 Rob PE1ITR http://www.pe1itr.com
I have the L band receiver off while I am doing testing on the transmit power level and battery discharge rate. I updated the AO-51 message to reflect this. The charge and discharge rates appear to have changed following the period of no eclipse that ended in April. As far as the digital downlink, you should be able to decode it without any problem if you are receiving a signal with a good S/N ratio. I can tell a good deal of difference between winter and summer receive levels, because of foliage, but get everything well once above the trees. I get data when through the trees, but not everything.
The transmit power has also been down due to the length of eclipse that peaked about 2 weeks ago and will continue to get shorter until Sept when we will see a no eclipse period for about 8 months.
This morning I set TXA to 430 mW (digital downlink) and TXB to 470 mW (analog downlink). So pretty good power levels for both transmitters. A month ago they were in the 340 mW range.
73, Gould, WA4SXM AO-51 command station
----- Original Message ----- From: "Rob Hardenberg PE1ITR" rob@itr-datanet.com To: amsat-bb@amsat.org Sent: Sunday, July 06, 2008 1:29 PM Subject: [amsat-bb] AO-51 L-Band Packet Uplink
Hi All,
I'am trying to access AO-51 9600Bd packet uplink on 1268.700MHz but had no succes so far. Maybe someone on the amsat bb group has some experience on this? I see on the downlink the message "Frames heard from PACB-1". I think it means the receiver is getting some signal but can't decode it. I believe my 23cm transmitter is working ok with 10w output into 26el yagi. Also the 9600bd is working OK because I can connect to local stations. I see no other traffic on the sat so it seems to me the L band receiver of ao-51 is not to sensitive.
73 Rob PE1ITR http://www.pe1itr.com
Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
Gould,
Great feedback that you provide to users, thanks!
It will be a few more weeks until I get my satellite ground station re-erected. I had a pretty good AO-40 station during that era and, with a house move in summer of 2006, I have not gotten it re-installed. I do have the ten-foot tower installed (which hinges over to the ground for antenna installationor maint.), so I hope get to installing the antennas, sometime soon. So, for now, I read the observations and comments with interest.
In time, I hope to be able to provide some telemetry reports. I'm guessing that mode-LU mode and 9K6 telemetry require some good frequency auto-tune and auto-tracking capabilities for unattended or hands-off observations. I hope to add that after the antennas and radio equipment are again operational.
We will look forward to Andrew's visit to the Alaska ARRL Hamfest in August to inform on latest happenings in Amsat.
73 Ed - KL7UW http://www.kl7uw.com/sat.htm http://www.akhamfest.com
At 09:48 AM 7/6/2008, Gould Smith wrote:
I have the L band receiver off while I am doing testing on the transmit power level and battery discharge rate. I updated the AO-51 message to reflect this. The charge and discharge rates appear to have changed following the period of no eclipse that ended in April. As far as the digital downlink, you should be able to decode it without any problem if you are receiving a signal with a good S/N ratio. I can tell a good deal of difference between winter and summer receive levels, because of foliage, but get everything well once above the trees. I get data when through the trees, but not everything.
The transmit power has also been down due to the length of eclipse that peaked about 2 weeks ago and will continue to get shorter until Sept when we will see a no eclipse period for about 8 months.
This morning I set TXA to 430 mW (digital downlink) and TXB to 470 mW (analog downlink). So pretty good power levels for both transmitters. A month ago they were in the 340 mW range.
73, Gould, WA4SXM AO-51 command station
----- Original Message ----- From: "Rob Hardenberg PE1ITR" rob@itr-datanet.com To: amsat-bb@amsat.org Sent: Sunday, July 06, 2008 1:29 PM Subject: [amsat-bb] AO-51 L-Band Packet Uplink
Hi All,
I'am trying to access AO-51 9600Bd packet uplink on 1268.700MHz but had no succes so far. Maybe someone on the amsat bb group has some experience on this? I see on the downlink the message "Frames heard from PACB-1". I think it means the receiver is getting some signal but can't decode it. I believe my 23cm transmitter is working ok with 10w output into 26el yagi. Also the 9600bd is working OK because I can connect to local stations. I see no other traffic on the sat so it seems to me the L band receiver of ao-51 is not to sensitive.
73 Rob PE1ITR http://www.pe1itr.com
Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. 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. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
participants (3)
-
Edward Cole -
Gould Smith -
Rob Hardenberg PE1ITR