More on the Greyline theory.
Gents, Don't give up on my "hare-brained" Greyline theory just yet. Remember ... it's not just a "flat" line on the globe we're talking discussing here.
For all intents and purposes "space" is 3 dimensional.
Thomas's point is IMPORTANT ... regarding illumination.
Half of the satellite may be illuminated while the other half isn't, much depends on the attitude in relation to the sun ... but some tracking software doesn't always predict these parameters and those that do hardly ever agree with eachother.
So which is correct? ... don't ask me !!!.
As long as the signals have been "booming" in nobody has bothered much about minor details and possible small perbutations. Now may be the time for a bit more study.
The following is a mail from Ken GW1FKY, with a *VERY* good suggestion for a beacon. I think we should support it ... coupled with my previous suggestion for a redundancy back-up system for a beacon ... it's a great idea.
We are now seeing now just how important the beacon is.
Interestingly, IMHO, AO-7 has taught more people more things about satellite operating than AO-51 ever will.
73 John. la2qaa@amsat.org
From: GW1FKY@aol.com Date: Thu, 11 Oct 2007 15:10:38 -0400 Subject: Re: [amsat-bb] The laws of physics. To: la2qaa@amsat.org
Hi John, Many thanks for your interesting observations and experiences with the operation of AO-7. I was wondering whether what you stated about the "Footprint " & the "Greyline" information is perhaps the key factor. As we are using software to predict the relative position against what might be the real point that the satellite sees illumination, is it perhaps a factor of error in the modelling that is used? Just a thought and it would be useful if could confirm the accuracy with future satellites if they had a beacon which did switch on as a result of solar illumination and not as a function of software or a timer. Regards Ken Eaton GW1FKY Amsat- UK Amsat -NA
Thanks to all for an intersting thread.
There is a possible way to check out the grey line in space. Monitor the 70cms CW beacon on LO-19. No code hams (like me) Use Hamscope or CWget and a soundcard to decode the Morse
Chanel 7 gives the solar panel voltage on the +Z surface of the satellite.
That excellent book, The Digital Satellite & Telemetry Guide by Gould Smith WA4SXM has all the details.
73 all
G7HIA
john heath g7hia@btinternet.com wrote:
> Monitor the 70cms CW beacon on LO-19. No > code hams (like me) Use Hamscope or CWget > and a soundcard to decode the Morse
I copied the CW at 2235 on 437.125 MHz and wrote down the following...
LUSAT HI HI AO AVA AB4 TDB ANU TDU ADE AV4 AE6
Is this helpful?
73, Gary -K8KFJ- West Virginia AMSAT #32574
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Hi,
Thanks to Garie for the LUSAT data which decodes to 20.1Volts from the solar panels on the +Z (top) face of the satellite.
Mike Ruprecht DK3WN has a neat telemetry utility on his web site. Type in the letter groups and read off the corresponding values. Thanks Mike, I use this a lot. www.mike-rupprecht.de ( hope its still on the site I downloaded it in 2006)
The Grey Line idea I had in mind was to take a series of values for +Z as the satellite passed from darkness, across the grey line then into sunlight. Compare these with the position of the greyline shown on a tracking program.
I see two obvious flaws in the idea. The telemetry from Lusat is not continious so there are short gaps in the data. The unknown time delay between the spacecraft software capturing the voltage value and transmitting it.
AO-51 has much more sophisticated telemetry data so perhaps this is a good experiment to try on AO-51, when the soundcard software is released. As far I can tell the currently available telemetry software only works with the output from a hardware modem (expensive).
BTW - you can see the grey line in space. Watch a visual of the ISS going West to East in the evening. The ISS is very bright near TCA and as it gets into the East the brightness diminishes, goes through a dull orange colour, then dissapears into the darkness.
73 John G7HIA
Good one !!!! John, thanks.
73 John 2. la2qaa@amsat.org ..........................................................................................
From: g7hia@btinternet.com To: la2qaa@amsat.org CC: amsat-bb@amsat.org Subject: Re: [amsat-bb] testing the gret line theory Date: Fri, 12 Oct 2007 16:05:03 +0100
Thanks to all for an intersting thread.
There is a possible way to check out the grey line in space. Monitor the 70cms CW beacon on LO-19. No code hams (like me) Use Hamscope or CWget and a soundcard to decode the Morse
Chanel 7 gives the solar panel voltage on the +Z surface of the satellite.
That excellent book, The Digital Satellite & Telemetry Guide by Gould Smith WA4SXM has all the details.
73 all
G7HIA
participants (3)
-
Garie Halstead K8KFJ -
John Hackett -
john heath