I thought I read we were supposed to experience degraded performance from AO-51 since last week's re-orientation of the bird.
I just worked the 5:04PM Pacific Standard Time / 01:04 GMT pass from DM03. Worked three countries along the West Coast, in addition to working Texas to the East. Elaborate station equipment involved ...
-handheld radio at 2.0W -handheld dual-band Yagi
Performance seems just fine out here, folks!
Clint Bradford, K6LCS http://www.work-sat.com
I tried again tonight on a 30 deg pass... no luck for me... Eggbeater, preamp, heliax.... gee ! It is really different !
73
2009/12/6 Clint Bradford clintbrad4d@earthlink.net:
I thought I read we were supposed to experience degraded performance from AO-51 since last week's re-orientation of the bird.
I just worked the 5:04PM Pacific Standard Time / 01:04 GMT pass from DM03. Worked three countries along the West Coast, in addition to working Texas to the East. Elaborate station equipment involved ...
-handheld radio at 2.0W -handheld dual-band Yagi
Performance seems just fine out here, folks!
Clint Bradford, K6LCS http://www.work-sat.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
I think the handheld ops have less trouble with the polarity switching because tend to compensate more quickly with a twist of the wrist.
At higher elevations, the fades are hardly noticeable here. At low elevations, the drop outs are similar to SO-50. It makes me wish I did have polarity switching.
73 Glenn AA5PK DM91 - San Angelo, TX
----- Original Message ----- From: "Clint Bradford" clintbrad4d@earthlink.net To: amsat-bb@amsat.org Sent: Sunday, December 06, 2009 7:59 PM Subject: [amsat-bb] AO-51 - After the Change
I thought I read we were supposed to experience degraded performance from AO-51 since last week's re-orientation of the bird.
I just worked the 5:04PM Pacific Standard Time / 01:04 GMT pass from DM03. Worked three countries along the West Coast, in addition to working Texas to the East. Elaborate station equipment involved ...
-handheld radio at 2.0W -handheld dual-band Yagi
Performance seems just fine out here, folks!
Clint Bradford, K6LCS http://www.work-sat.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
... I think the handheld ops have less trouble with the polarity
switching because tend to compensate more quickly with a twist of the wrist ...
That phenomenon is not evident now - nor has it ever been - for me on AO-51.
I know the engineers say I am supposed to be increasing or decreasing my signal strength by 22 or 23db by merely twisting my Yagi 90 degrees. But I have hundreds of witnesses during dozens of demonstrations who will tell you that when the Yagi is turned 90 degrees, there's no discernible change in the signal.
This is not a scientific approach to the subject, of course. Just what my aging ears can hear.
I have heard fellow AMSAT members describe AO-51's "signal fading due to the satellite tumbling in space," too. I am not using elaborate equipment, but have no idea what they are talking about.
Just my firsthand observations. Guess I could be wrong ... we are a little different - I am told - out hre on the West Coast of the US.
Clint Bradford, K6LCS
I experience this drastic polarity changing here ever since the change, and like SO-50, have to keep one finger on the polarity switch.........maybe my aging ears arent as good as my aging KLM's? Will be glad when they can reverse what they did afew weeks back. Also I notice the signal is not as strong now, as instead of picking up the bird at 1-2 degs above horizon, it is now 6-8 degrees.
John W6ZKH on the Left Coast of the Sierras
----- Original Message ----- From: "Clint Bradford" clintbrad4d@earthlink.net To: "Glenn AA5PK" aa5pk@suddenlink.net Cc: amsat-bb@amsat.org Sent: Sunday, December 6, 2009 7:15:19 PM GMT -08:00 US/Canada Pacific Subject: [amsat-bb] Re: AO-51 - After the Change
... I think the handheld ops have less trouble with the polarity
switching because tend to compensate more quickly with a twist of the wrist ...
That phenomenon is not evident now - nor has it ever been - for me on AO-51.
I know the engineers say I am supposed to be increasing or decreasing my signal strength by 22 or 23db by merely twisting my Yagi 90 degrees. But I have hundreds of witnesses during dozens of demonstrations who will tell you that when the Yagi is turned 90 degrees, there's no discernible change in the signal.
This is not a scientific approach to the subject, of course. Just what my aging ears can hear.
I have heard fellow AMSAT members describe AO-51's "signal fading due to the satellite tumbling in space," too. I am not using elaborate equipment, but have no idea what they are talking about.
Just my firsthand observations. Guess I could be wrong ... we are a little different - I am told - out hre on the West Coast of the US.
Clint Bradford, K6LCS
_______________________________________________ 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
Clint, Rotating a linear polarized Yagi in a circularly polarized field should result in less than a few dB of change, no change if the circular antenna is perfectly circularly polarized. When using a linear antenna ground effects including reflections will cause a larger change. Using circular on both ends will result in less fading from the ground effects and no change in signal for antenna rotation on the S/C side providing the S/C antenna has a good pointing angle. Losses of 22 +dB are reserved for cross polarization of antennas H-V and LH to RH.
Art, KC6UQH
-----Original Message----- From: amsat-bb-bounces@amsat.org [mailto:amsat-bb-bounces@amsat.org] On Behalf Of Clint Bradford Sent: Sunday, December 06, 2009 7:15 PM To: Glenn AA5PK Cc: amsat-bb@amsat.org Subject: [amsat-bb] Re: AO-51 - After the Change
... I think the handheld ops have less trouble with the polarity
switching because tend to compensate more quickly with a twist of the wrist ...
That phenomenon is not evident now - nor has it ever been - for me on AO-51.
I know the engineers say I am supposed to be increasing or decreasing my signal strength by 22 or 23db by merely twisting my Yagi 90 degrees. But I have hundreds of witnesses during dozens of demonstrations who will tell you that when the Yagi is turned 90 degrees, there's no discernible change in the signal.
This is not a scientific approach to the subject, of course. Just what my aging ears can hear.
I have heard fellow AMSAT members describe AO-51's "signal fading due to the satellite tumbling in space," too. I am not using elaborate equipment, but have no idea what they are talking about.
Just my firsthand observations. Guess I could be wrong ... we are a little different - I am told - out hre on the West Coast of the US.
Clint Bradford, K6LCS
_______________________________________________ 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
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Art - What you wrote (and correct me if I misinterpreted) is that me - and others with mere handheld Yagi antennas - are achieving better results on the FM birds than those with more sophisticated linear antennas.
Clint
On Dec 6, 2009, at 10:31 PM, Art McBride wrote:
Clint, Rotating a linear polarized Yagi in a circularly polarized field should result in less than a few dB of change, no change if the circular antenna is perfectly circularly polarized. When using a linear antenna ground effects including reflections will cause a larger change. Using circular on both ends will result in less fading from the ground effects and no change in signal for antenna rotation on the S/C side providing the S/C antenna has a good pointing angle. Losses of 22 +dB are reserved for cross polarization of antennas H-V and LH to RH.
participants (5)
-
Art McBride -
Clint Bradford -
Glenn AA5PK -
Jean-François Ménard -
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