I’ve put out calls a number of times on AO-07 as it passes over Australia and while I hear my own single back clearly I’ve never had a reply. I guess I’m curious if there is a calling protocol I’m missing, or a particular part of the passband etc? As a higher altitude bird with great coverage it would seems logical to me that it would be popular? Am I missing something?
James.
It takes a little more effort to utilize either Mode A or Mode B than a handheld radio and a handheld antenna like many are using to access the FM satellites. Also, at least in this country, a fair number of operators have only FM equipment for either 2-meters or 70 cm and not CW / SSB equipment that is required to operate through OSCAR VII. As such, much less activity than when the satellite first went "up" in the 1970s. Glen, K9STH AMSAT-239 / LM-463 Website: https://k9sth.net
On Tuesday, September 10, 2019, 07:23:47 AM CDT, James Pierce via AMSAT-BB [email protected] wrote:
I’ve put out calls a number of times on AO-07 as it passes over Australia and while I hear my own single back clearly I’ve never had a reply. I guess I’m curious if there is a calling protocol I’m missing, or a particular part of the passband etc? As a higher altitude bird with great coverage it would seems logical to me that it would be popular? Am I missing something?
AO-7 also works best in a small sweet spot in its passband. If you don't know that it can be frustrating to hear yourself all garbled. All that said, I think most linears have relatively low use. What is your experience in Australia with the XW satellites (which work absolutely great!)?
On Tue, Sep 10, 2019 at 8:24 AM James Pierce via AMSAT-BB < [email protected]> wrote:
I’ve put out calls a number of times on AO-07 as it passes over Australia and while I hear my own single back clearly I’ve never had a reply. I guess I’m curious if there is a calling protocol I’m missing, or a particular part of the passband etc? As a higher altitude bird with great coverage it would seems logical to me that it would be popular? Am I missing something?
James. _______________________________________________ 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: https://www.amsat.org/mailman/listinfo/amsat-bb
The XW's and CAS-4'S are loud and easy to use, in my opinion. I have managed varying levels of success with AO-7, it is my linear unicorn; as AO-85 is my FM unicorn.
Even with the lower 48 mostly being in a XW/CAS-4 pass they can be full of dead bandpass.
On Tue, Sep 10, 2019, 12:39 Burns Fisher via AMSAT-BB [email protected] wrote:
AO-7 also works best in a small sweet spot in its passband. If you don't know that it can be frustrating to hear yourself all garbled. All that said, I think most linears have relatively low use. What is your experience in Australia with the XW satellites (which work absolutely great!)?
On Tue, Sep 10, 2019 at 8:24 AM James Pierce via AMSAT-BB < [email protected]> wrote:
I’ve put out calls a number of times on AO-07 as it passes over Australia and while I hear my own single back clearly I’ve never had a reply. I guess I’m curious if there is a calling protocol I’m missing, or a particular part of the passband etc? As a higher altitude bird with great coverage it would seems logical to me that it would be popular? Am I missing something?
James. _______________________________________________ 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: https://www.amsat.org/mailman/listinfo/amsat-bb
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: https://www.amsat.org/mailman/listinfo/amsat-bb
Where is the sweet spot?
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-------- Original Message -------- On Sep 10, 2019, 11:37 AM, Burns Fisher via AMSAT-BB wrote:
AO-7 also works best in a small sweet spot in its passband. If you don't know that it can be frustrating to hear yourself all garbled. All that said, I think most linears have relatively low use. What is your experience in Australia with the XW satellites (which work absolutely great!)?
On Tue, Sep 10, 2019 at 8:24 AM James Pierce via AMSAT-BB < [email protected]> wrote:
I’ve put out calls a number of times on AO-07 as it passes over Australia and while I hear my own single back clearly I’ve never had a reply. I guess I’m curious if there is a calling protocol I’m missing, or a particular part of the passband etc? As a higher altitude bird with great coverage it would seems logical to me that it would be popular? Am I missing something?
James. _______________________________________________ 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: https://www.amsat.org/mailman/listinfo/amsat-bb
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: https://www.amsat.org/mailman/listinfo/amsat-bb
Where is the sweet spot?
The link below is a screen shot that I took one day back in March when a strong CW signal killed the transponder on AO-7. Before the 2m downlink went offline you can see the three places that I believe people are referring to.
Looks to me like 145.928, 145.943, & 145.959, more or less.
Here's that image:
https://www.dropbox.com/s/ztffqf1afwdmrt0/screen.png?raw=1
I have vastly less experience on the linear transponders than most, but here are a couple of things I've noticed repeatedly that might be helpful on AO-7.
#1, there is a LOT of difference in downlink signal strength from one pass to the next. So, if you hear little or no traffic on the transponder, it's not necessarily anything you are doing wrong.
#2, don't overlook the low-elevation period at the beginning or end of a pass. I've often noticed downlink signals 2 or 3 times stronger on AO-7 just after AOS and just before LOS.
#3, it's a shared resource. So, if you see (on an SDR waterfall) or hear another station with an extremely strong signal, it might be worth waiting to transmit until they stop -- your signal will probably be much more effective
#4, I've noticed that when I take off my headphones and stop the recorder, signals instantly jump to max scale! If you can perfect a move where you FAKE taking off your headphones and only PRETEND to stop the recorder, you might have a shot at some of the best audio you've heard via satellite.
-Scott, K4KDR
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----Original Message----- From: Doug Phelps via AMSAT-BB Sent: Saturday, September 21, 2019 2:20 PM To: [email protected] ; [email protected] Cc: [email protected] Subject: Re: [amsat-bb] AO-07 Popularity?
Where is the sweet spot?
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-------- Original Message -------- On Sep 10, 2019, 11:37 AM, Burns Fisher via AMSAT-BB wrote:
AO-7 also works best in a small sweet spot in its passband. If you don't know that it can be frustrating to hear yourself all garbled. All that said, I think most linears have relatively low use. What is your experience in Australia with the XW satellites (which work absolutely great!)?
On Tue, Sep 10, 2019 at 8:24 AM James Pierce via AMSAT-BB < [email protected]> wrote:
I’ve put out calls a number of times on AO-07 as it passes over Australia and while I hear my own single back clearly I’ve never had a reply. I guess I’m curious if there is a calling protocol I’m missing, or a particular part of the passband etc? As a higher altitude bird with great coverage it would seems logical to me that it would be popular? Am I missing something?
James.
participants (6)
-
Burns Fisher -
Don KB2YSI -
Doug Phelps -
Glen Zook -
James Pierce -
Scott