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CX2SA > SATDIG 26.08.11 20:06l 341 Lines 11102 Bytes #999 (0) @ WW
BID : AMSATBB6491
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Subj: AMSAT-BB-digest V6 491
Path: IZ3LSV<IK2XDE<DB0RES<ON0AR<HS1LMV<CX2SA
Sent: 110826/1904Z @:CX2SA.LAV.URY.SA #:24043 [Minas] FBB7.00e $:AMSATBB6491
From: CX2SA@CX2SA.LAV.URY.SA
To : SATDIG@WW
Today's Topics:
1. Re: ISS Re-supply Spacecraft Fails (B J)
2. Re: some exceedingly clever technology (Gregg Wonderly)
3. em45 (wa4hfn@xxxxxxx.xxxx
4. EL18/19 activation (Wadhah Al-Tailji (WA5DA))
5. Re: ARISSat-1 voice telemetry 00:27z 8/21/11 (Phil Karn)
6. Re: some exceedingly clever technology (Phil Karn)
7. Iss Packet (mm0kjg)
8. NASA Space Station Status Briefing (Clint Bradford)
----------------------------------------------------------------------
Message: 1
Date: Fri, 26 Aug 2011 14:47:11 +0000
From: B J <va6bmj@xxxxx.xxx>
To: amsat-bb <amsat-bb@xxxxx.xxx>
Subject: [amsat-bb] Re: ISS Re-supply Spacecraft Fails
Message-ID:
<CAP7QzkPEzGW0rwkMHgN8WcdTaqaaQ9a4CgpBUuNFa0Ze5T3YfA@xxxx.xxxxx.xxx>
Content-Type: text/plain; charset=ISO-8859-1
On Fri, Aug 26, 2011 at 1:13 PM, Jeffrey Koehler <jeffk13057@xxxxx.xxx>wrote:
> Well, I remember seeing it as an ABC Movie of the Week or something, so you
> can't be that much older than me.
> The cool stuff I remember is that I believe audio was caught from the
> Plantronics headsets in the spacecraft. Also, if I remember correctly, I
> think there were quindars in comms from the ground.
> I wanna see if Netflix has it...I wanna see it again all of the sudden.
>
>
<snip>
TCM has shown it from time to time in the last few years.
73s
Bernhard VA6BMJ @ DO33FL
------------------------------
Message: 2
Date: Fri, 26 Aug 2011 10:25:09 -0500
From: Gregg Wonderly <w5ggw@xxx.xxx>
To: R Oler <orbitjet@xxxxxxx.xxx>
Cc: Amsat BB <amsat-bb@xxxxx.xxx>
Subject: [amsat-bb] Re: some exceedingly clever technology
Message-ID: <4E57BAD5.5080506@xxx.xxx>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
This is exactly the kind of low tech solution that we need to use in amateur
sats to have orientation and orbital control. But, I worry that if we did
demonstrate control, would we be allowed to "be in control" since the craft
could then become a weapon in the hands of the wrong person.
Gregg
W5GGW
On 8/24/2011 10:11 PM, R Oler wrote:
>
> http://onorbit.com/node/3709
>
> Robert G. Oler WB5MZO Life member AMSAT ARRL NARS
>
> _______________________________________________
> Sent via AMSAT-BB@xxxxx.xxx. 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
>
------------------------------
Message: 3
Date: Fri, 26 Aug 2011 15:29:50 +0000 (UTC)
From: wa4hfn@xxxxxxx.xxx
To: AMSAT <amsat-bb@xxxxx.xxx>
Subject: [amsat-bb] em45
Message-ID:
<1779836528.925118.1314372590503.JavaMail.root@xxxxxxx.xxxxxxxxxxx.xx.xxxx.xxx
xxxx.xxx>
Content-Type: text/plain; charset=utf-8
I will try some satellite passes to day as work will allow SO50 AO27 and
AO51 from EM45
WA4HFN Damon
------------------------------
Message: 4
Date: Fri, 26 Aug 2011 10:10:08 -0500
From: "Wadhah Al-Tailji (WA5DA)" <wa5da@xxxx.xxx>
To: amsat-bb@xxxxx.xxx
Subject: [amsat-bb] EL18/19 activation
Message-ID:
<CAOwz7kRchbSSUWCF5h51xH-0R=A8wPrxSz91YX-OG8bi9Bh2Kw@xxxx.xxxxx.xxx>
Content-Type: text/plain; charset=ISO-8859-1
Over the next few days ('til around Tuesday 8/30) I will be near the
EL18/19 border and will try to work the FM sats (SO-50, AO-27, AO-51)
from there. I cannot guarantee any specific times or passes due to my
unpredictable work schedule (which includes the weekend), so stations
needing these grids will just need to keep an ear out for me.
If anybody needs EL08 or EL09, please e-mail me to try to work out a
schedule. I am actually near the corner of EL08/09/18/19 but will
focus on the rarer EL18/19 pair since the corner itself is
inaccessible.
Thanks,
Wadhah, WA5DA
------------------------------
Message: 5
Date: Fri, 26 Aug 2011 09:36:50 -0700
From: Phil Karn <karn@xxxxxxxx.xxx>
To: "Greg D." <ko6th_greg@xxxxxxx.xxx>
Cc: amsat-bb@xxxxx.xxx
Subject: [amsat-bb] Re: ARISSat-1 voice telemetry 00:27z 8/21/11
Message-ID: <4E57CBA2.8070706@xxxxxxxx.xxx>
Content-Type: text/plain; charset=ISO-8859-1
On 8/22/11 9:18 PM, Greg D. wrote:
>
> Ah, interesting. So, values around +/- 0 mean that the battery is
> (or thinks it is) fully charged, and the satellite is running on just
> the solar panels. Since that happens pretty quickly after start-up
> (low MET values), that certainly supports the conclusion that the
> battery has nearly zero capacity left in it.
>
> But if it's "fully charged", there must be something else going on
I think it supports the conclusion that the battery has become an open
circuit. The voltage wouldn't get that high if multiple cells had
shorted. This is lucky for us since the satellite can continue to
operate on the solar panels when lit.
I'm really beginning to think about new ideas for satellite power
systems, especially Lou McFaddin's idea (published some years ago at the
Symposium) for a modular power system with a parallel bus. Each battery
is in a module with its own microprocessor and DC-DC converter to match
the standard bus voltage, and each is designed to remove itself from the
bus when its battery fails.
What's nice about this is that it's very easy to combine different
battery technologies and even supercaps and have the system degrade
gracefully over time. The computer would keep track of the total
available capacity, and at first it could operate all systems normally
through eclipse. As modules fail, it would shut down non-essential
systems one by one as necessary during during eclipse until the sun
reappears. The highest priority load would be the IHU memory. With some
supercaps in the mix it should always be able to keep the computer
alive. That would avoid a lot of spurious computer resets and associated
loss of information like recorded telemetry and store-and-forward messages.
-Phil, KA9Q
------------------------------
Message: 6
Date: Fri, 26 Aug 2011 09:54:22 -0700
From: Phil Karn <karn@xxxxxxxx.xxx>
To: R Oler <orbitjet@xxxxxxx.xxx>
Cc: Amsat BB <amsat-bb@xxxxx.xxx>
Subject: [amsat-bb] Re: some exceedingly clever technology
Message-ID: <4E57CFBE.7000906@xxxxxxxx.xxx>
Content-Type: text/plain; charset=ISO-8859-1
On 8/24/11 8:11 PM, R Oler wrote:
>
> http://onorbit.com/node/3709
Thrusters are necessary for orbit control, but for attitude control
(which I think we really need) you'd *really* prefer something that
doesn't consume a fuel.
These attitude control systems come in basically two types:
magnetorquers and reaction wheels. Magnetorquers exchange angular
momentum with the earth by acting on its magnetic field, but they tend
to be slow, imprecise and require complex control and sensing systems
including a magnetometer far enough from the spacecraft to get away from
its own magnetic fields.
Reaction wheels come in two kinds: momentum wheels and control moment
gyros. Momentum wheels change speed while control moment gyros don't.
The latter seem much more common in spacecraft but I'd investigate both.
They're good for quick, accurate pointing like you'd need to keep an
antenna pointed down or a solar panel pointed at the sun.
Having both a magnetorquer and a set of wheels can be advantageous as
the magnetorquer can be used occasionally to dump accumulated angular
momentum from the wheels should it build up from small external torques.
Controlling attitude also means measuring it, and for this I keep
thinking about small, cheap CCD video cameras. If we could build good
enough sunshades we could snap pictures of star fields and look them up
in a database. If you can match multiple stars in an image, then a
single image could fix the attitude of the spacecraft. But I'd want to
put a camera on each surface if possible. They could also sense the sun
and the earth, though that's not as simple as it might seem. The sun
usually overloads a CCD and produces streaks while the earth is very
large in LEO. It might be possible to recognize the limb of the earth
and get better precision that way. A lot would depend on the software
processing these images, and it would be a challenge to write.
-Phil, KA9Q
------------------------------
Message: 7
Date: Fri, 26 Aug 2011 19:32:55 +0100
From: mm0kjg <mm0kjg@xxxxxxxxxx.xxx>
To: <amsat-bb@xxxxx.xxx>
Subject: [amsat-bb] Iss Packet
Message-ID: <000301cc641e$93adf730$6a01a8c0@xxxxx>
Content-Type: text/plain; format=flowed; charset="iso-8859-1";
reply-type=original
Hello all again.
Can some good person help me try packet on the Iss 145.825. I have Multipsk
and also Mixw on my pc so hopefully one of these will allow me to send
packet via soundcard to my Ic-910. Have a Cat cable and audio in and out
from the din connection on back of radio so what next?. Is both Tx and rec
on 145.825.
Cheers Kev
mm0kjg
------------------------------
Message: 8
Date: Fri, 26 Aug 2011 11:34:49 -0700
From: Clint Bradford <clintbradford@xxx.xxx>
To: AMSAT BB <amsat-bb@xxxxx.xxx>
Subject: [amsat-bb] NASA Space Station Status Briefing
Message-ID: <0BF2E9EC-0C9A-4C00-824D-3464ACB41DB6@xxx.xxx>
Content-Type: text/plain; CHARSET=US-ASCII
Aug. 26, 2011
Michael Curie
Headquarters, Washington
202-358-1100
michael.curie@xxxx.xxx
Kelly Humphries
Johnson Space Center, Houston
281-483-5111
kelly.o.humphries@xxxx.xxx
MEDIA ADVISORY: M11-180
NASA SETS SPACE STATION STATUS UPDATE BRIEFING FOR MONDAY
HOUSTON -- NASA Television will broadcast an International Space
Station status update briefing at 9 a.m. CDT on Monday, Aug. 29.
Michael Suffredini, space station program manager, will provide the
latest information on the status of the station following the Aug. 24
failure of the Russian Progress 44 resupply vehicle to reach orbit.
The Russian Federal Space Agency has established a commission to
assess the root cause of the failure, to develop a plan of corrective
action, and determine any implications for the launch of crews to the
station on similar Soyuz rockets. Suffredini also will discuss the
status of the commission's investigation and preliminary plans by
NASA and its international partners to resume crew and cargo
launches.
NASA TV and the agency's website will broadcast the briefing live from
the Johnson Space Center. Reporters may ask questions from
participating NASA locations, and should contact their preferred NASA
center to confirm participation. The phone bridge at Johnson will be
available for reporters to participate by calling the newsroom at
281-483-5111 by 8:45 a.m.
For the latest information about the International Space Station,
visit:
http://www.nasa.gov/station
For schedule, streaming and downlink information about NASA TV, visit:
http://www.nasa.gov/ntv
-end-
Clint Bradford
clintbradford@xxx.xxx
------------------------------
_______________________________________________
Sent via amsat-bb@xxxxx.xxx. Opinions expressed are those of the author.
Not an AMSAT member? Join now to support the amateur satellite program!
http://amsat.org/mailman/listinfo/amsat-bb
End of AMSAT-BB Digest, Vol 6, Issue 491
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