INTERMITTANT DOWNLINK HEARD - CAS-4A transponder freq
to All, this is to confirm my status report on the website, (in case you think it was a mistake)
on July 27 2017, at about 0047UTC I could hear my downlink, although intermittently, during a pass of CAS-4A (using the published frequencies). The downlink had good audio (loud and clear), and I could only hear a few words of my transmission at a time. I was able to sustain for only a portion of the pass. Using 5Watts into a M2 16 el cross element circular beam. (436CP16). This pass did NOT coincide with any of the XW sats.
73, Christy KB6LTY, DM14
--- This email has been checked for viruses by AVG. http://www.avg.com
Had hopes of monitoring some voice transponder activity on a high pass of CAS-4A this evening, but nothing heard.
The telemetry data stream and CW beacon were strong as ever, but nothing around the transponder downlink.
Image of SDR waterfall:
http://www.qsl.net/k/k4kdr//files/2017-07-27--2124--CAS-4A.png
Question: in a case like this where the status of a transponder is unknown and no activity is heard, absent any SSB gear would it be bad to transmit an FM signal on the uplink just to see if the transponder is in fact active? I would never use FM if there was activity, but could an FM transmission cause any harm just to possibly determine the status of a transponder?
Thanks!
-Scott, K4KDR
==========================
On Wed, Jul 26, 2017 at 9:31 PM, christy hunter [email protected] wrote:
to All, this is to confirm my status report on the website, (in case you think it was a mistake)
on July 27 2017, at about 0047UTC I could hear my downlink, although intermittently, during a pass of CAS-4A (using the published frequencies). The downlink had good audio (loud and clear), and I could only hear a few words of my transmission at a time. I was able to sustain for only a portion of the pass. Using 5Watts into a M2 16 el cross element circular beam. (436CP16). This pass did NOT coincide with any of the XW sats.
73, Christy KB6LTY, DM14
An FM signal with no modulation is theoretically just a carrier, no different from CW. So it wouldn't really be a problem to send a couple of quick transmissions to test it out.
FM signals won't harm a transponder, but they will cause a lot of problems for others trying to use the transponder.
73,
Paul, N8HM
On Thu, Jul 27, 2017 at 17:41 Scott [email protected] wrote:
Had hopes of monitoring some voice transponder activity on a high pass of CAS-4A this evening, but nothing heard.
The telemetry data stream and CW beacon were strong as ever, but nothing around the transponder downlink.
Image of SDR waterfall:
http://www.qsl.net/k/k4kdr//files/2017-07-27--2124--CAS-4A.png
Question: in a case like this where the status of a transponder is unknown and no activity is heard, absent any SSB gear would it be bad to transmit an FM signal on the uplink just to see if the transponder is in fact active? I would never use FM if there was activity, but could an FM transmission cause any harm just to possibly determine the status of a transponder?
Thanks!
-Scott, K4KDR
==========================
On Wed, Jul 26, 2017 at 9:31 PM, christy hunter [email protected] wrote:
to All, this is to confirm my status report on the website, (in case you think it was a mistake)
on July 27 2017, at about 0047UTC I could hear my downlink, although intermittently, during a pass of CAS-4A (using the published
frequencies).
The downlink had good audio (loud and clear), and I could only hear a few words of my transmission at a time. I was able to sustain for only a portion of the pass. Using 5Watts into a M2 16 el cross element circular beam. (436CP16). This pass did NOT coincide with any of the XW sats.
73, Christy KB6LTY, DM14
Sent via [email protected]. 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 Thu, Jul 27, 2017 at 05:40:39PM -0400, Scott wrote:
Question: in a case like this where the status of a transponder is unknown and no activity is heard, absent any SSB gear would it be bad to transmit an FM signal on the uplink just to see if the transponder is in fact active? I would never use FM if there was activity, but could an FM transmission cause any harm just to possibly determine the status of a transponder?
Just make sure to ID at the end of your transmission. You can do this by using your PTT as a key.
... otherwise, you're just kerchunking a repeater. :-)
--- Zach N0ZGO
participants (4)
-
christy hunter -
Paul Stoetzer -
Scott -
Zach Metzinger