Re: Digital QRM on FO-29 (DF opportunity!)
Wow, a GREAT DF opportunity and exercise. The Doppler info is there to determine its location. Just plot the doppler and note the center point and draw a line of bearing through it. Combine with others and find the source.
heh heh... though, complicated by having to subtract out your own... But we should develop these techniques. They are the basis of all of the original Search And Rescue satellite systems.
In fact!!! Why not get a few hams in a few areas of the country to operate a CW carrier (at low power) at a known frequency in 4 corners of the US and let evreyone practice their techniques. This way, we learn how to do it on a known signal.
Just a thought.
Bob, WB4APR
On Fri, Oct 4, 2013 at 4:51 PM, Paul Stoetzer [email protected] wrote:
During two passes of FO-29 - at around 0120Z last night and around 1430Z this morning, I've heard some QRM that sounds like a digital signal. I confirmed that others heard it too and it wasn't local QRM, so it's obviously being relayed by the satellite. Downlink is around 435.860 MHz (I heard it around 435.865 last night as the satellite was approaching and around 435.855 MHz this morning as the satellite was moving away), so the signal is likely being transmitted around 145.940 MHz.
Has anybody else heard it? Any ideas on what the source might be?
73,
Paul Stoetzer, N8HM Washington, DC _______________________________________________ Sent via [email protected]. 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
At one point, folks were using PSK31 on FO-29.
Check the waterfall and see how it looks like :-)
Stefan, VE4NSA
On Sat, Oct 5, 2013 at 8:25 AM, Robert Bruninga [email protected] wrote:
Wow, a GREAT DF opportunity and exercise. The Doppler info is there to determine its location. Just plot the doppler and note the center point and draw a line of bearing through it. Combine with others and find the source.
heh heh... though, complicated by having to subtract out your own... But we should develop these techniques. They are the basis of all of the original Search And Rescue satellite systems.
In fact!!! Why not get a few hams in a few areas of the country to operate a CW carrier (at low power) at a known frequency in 4 corners of the US and let evreyone practice their techniques. This way, we learn how to do it on a known signal.
Just a thought.
Bob, WB4APR
On Fri, Oct 4, 2013 at 4:51 PM, Paul Stoetzer [email protected] wrote:
During two passes of FO-29 - at around 0120Z last night and around 1430Z this morning, I've heard some QRM that sounds like a digital signal. I confirmed that others heard it too and it wasn't local QRM, so it's obviously being relayed by the satellite. Downlink is around 435.860 MHz
(I
heard it around 435.865 last night as the satellite was approaching and around 435.855 MHz this morning as the satellite was moving away), so the signal is likely being transmitted around 145.940 MHz.
Has anybody else heard it? Any ideas on what the source might be?
73,
Paul Stoetzer, N8HM Washington, DC _______________________________________________ Sent via [email protected]. 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 [email protected]. 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
It definitely wasn't PSK31. I'll post the audio of it when I get a chance tomorrow.
73,
Paul, N8HM
On 10/5/2013 10:09 AM, Stefan Wagener wrote:
At one point, folks were using PSK31 on FO-29.
Check the waterfall and see how it looks like :-)
Stefan, VE4NSA
On Sat, Oct 5, 2013 at 8:25 AM, Robert Bruninga <[email protected] mailto:[email protected]> wrote:
Wow, a GREAT DF opportunity and exercise. The Doppler info is there to determine its location. Just plot the doppler and note the center point and draw a line of bearing through it. Combine with others and find the source. heh heh... though, complicated by having to subtract out your own... But we should develop these techniques. They are the basis of all of the original Search And Rescue satellite systems. In fact!!! Why not get a few hams in a few areas of the country to operate a CW carrier (at low power) at a known frequency in 4 corners of the US and let evreyone practice their techniques. This way, we learn how to do it on a known signal. Just a thought. Bob, WB4APR On Fri, Oct 4, 2013 at 4:51 PM, Paul Stoetzer <[email protected] <mailto:[email protected]>> wrote: > During two passes of FO-29 - at around 0120Z last night and around 1430Z > this morning, I've heard some QRM that sounds like a digital signal. I > confirmed that others heard it too and it wasn't local QRM, so it's > obviously being relayed by the satellite. Downlink is around 435.860 MHz (I > heard it around 435.865 last night as the satellite was approaching and > around 435.855 MHz this morning as the satellite was moving away), so the > signal is likely being transmitted around 145.940 MHz. > > Has anybody else heard it? Any ideas on what the source might be? > > 73, > > Paul Stoetzer, N8HM > Washington, DC > _______________________________________________ > Sent via [email protected] <mailto:[email protected]>. 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 [email protected] <mailto:[email protected]>. 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)
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Paul Stoetzer -
Robert Bruninga -
Stefan Wagener