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[jamsat-news:1887] ANS-039 AMSAT Weekly Bulletins



ANS is a free, weekly, news and information service of AMSAT North
America, The Radio Amateur Satellite Corporation. ANS reports on
the activities of a worldwide group of Amateur Radio operators who
share an active interest in designing, building, launching and
communicating through analog and digital Amateur Radio satellites.

In this edition:
*  AO-40 Recovery Efforts Continue
*  OSCAR SKN Best Fist winners
*  ARISS Status
*  Youngest Amateur Extra announces success via ARISS PBBS
*  This Week's News in Brief

SB SAT @ AMSAT $ANS-039.01
AO-40 Recovery Efforts Continue

AMSAT News Service Bulletin 039.01 From AMSAT HQ
SILVER SPRING, MD.  February 8, 2004
BID: $ANS-039.01

The AO-40 command team has established a routine of trying to cycle the
main battery off (aux. battery on)  and then the S2 Tx ON every orbit,
using simple machine codes.  Following this, the sequence to disconnect all
transmitters is sent, to protect them from low voltage.  If we have
approximately 10 volts on the main buss, then these commands should be
making it through, but the S2 transmitter was not designed to run below 20
volts and is not coming on.  The battery relay has been tested in the AMSAT
lab, where a duplicate exists, and it will cycle reliably at 12 volts, but
not lower.   If we have less than 10 volts, then the commands will not be
received because the IHU-1 and/or command receivers are insufficiently
powered.  Either way, the IHU-1 is not currently running IPS.  The machine
code commands only function in reset mode.   We assume that we currently
have less than 12 volts and that either the IHU-1 and relay are not
functional (<10 volts) or the relay isn't functional (<12 volts), because
cycling the relay should get us out of this situation by disconnecting the
main battery.

With regard to the stability of the attitude/spin, this will not be a
concern for a very long time.  We are currently rotating at 3.5 RPM.  The
spin decay rate is extremely slow.  It will take approximately 4 years to
drop this to 3.0 RPM.  We can magnetorque at speeds as low as 1.5 RPM.  The
mystery effect will decrease ALON approximately 11.5 degrees/week.  It does
not affect ALAT, though ALAT will change slightly as the orbit precesses.

MAIN BATTERY NOTES (and conjecture):
The main batteries consist of three packs housed in sheet aluminum cases
and bolted to the radial braces between panels 1/6, 2/3 and 4/5.  The cells
within the packs have threaded metal binding posts and the cells are
connected by thick metal straps with strain relief "U's" in them.  The pack
at 2/3 consists of 7 cells and is the negative end of the chain.  The pack
at 1/6 consists of 6 cells and is in the middle of the chain.  The pack at
4/5 consists of 7 cells and is at the positive end of the chain.   The main
battery pack at 1/6 is the closest battery to the "flaky" heat pipe
thermistor, though it is located "below" this heat pipe near the omni end
of the spacecraft.  Main battery packs 4/5 and 1/6 lost their thermistors
during the 400N incident.  Whether this was due to trauma to the battery or
damage to the cabling is unknown.  If a short to ground occurred in the 1/6
battery pack it would pull the cells on the negative side of the short in
this pack to zero, as well as all cells in the 2/3 pack.   Depending on the
location of the short and the status of the cells in pack 4/5, this could
pull the main buss voltage to half normal (14 volts) or even 10 volts or
below. <conjecture> A short at this location might have generated enough
localized heat (or even some hot metal spatter)  to damage the thermistor
on the flaky heatpipe or, more likely, its wiring.  This is appealing
because it would represent a single point failure, rather than a failure
cascade.  One piece of evidence that doesn't clearly fit with this theory
is that the cells in pack 2/3, the one main battery pack that still has a
thermistor temperature sensor, do not appear to get warm following the
voltage drop.  We do not know how much capacity remained in these
cells.  It is possible they contained relatively little energy.

As several of you indicated, we are in a waiting game for the main battery
to develop one "open" cell.

[ANS thanks Stacey, W4SM, for the above information]


SB SAT @ AMSAT $ANS-039.02
OSCAR SKN Best Fist winners

AMSAT News Service Bulletin 039.02 From AMSAT HQ
SILVER SPRING, MD.  February 8, 2004
BID: $ANS-039.02

Many thanks to all who participated in AMSAT-NA's 32nd annual Straight Key
Night on OSCAR, 1 January 2004.  With only AO-7 and FO-29 available for use
this year, the activity level was down from the record high participation of
2003, but as always a good time was had by all who took part.

Our Best Fist winners for 2004, each nominated by someone he worked, are:

Richard Limebear, G3RWL
Cliff Buttschardt, K7RR
Keith O'Brien, N4ZQ
Al Ozias, N7EQF
Al Tribble, W3STW

Congratulations to all.

See you all next year!

[ANS thanks Ray, W2RS, for the above information]


 SB SAT @ AMSAT $ANS-039.03
ARISS Status

AMSAT News Service Bulletin 039.03 From AMSAT HQ
SILVER SPRING, MD.  February 8, 2004
BID: $ANS-039.03

1.  School Contacts

On January 28, The King's School in Canterbury, England experienced a
successful ARISS contact with Mike Foale, KB5UAC. Twelve questions were
asked and answered. Students and teachers as well as the Lord Mayor of
Canterbury, the school's dignitaries, the RSGB and AMSAT UK representatives
were in the audience. Meridian TV, BBC TV, BBC Radio Kent, Invicta Radio,
and the Kent Gazette covered the contact, and broadcast the event in their
main news. The BBC World Service and the Press Association asked for
information and transcripts.

An ARISS contact has also been scheduled for James Bay Elementary School in
Houston, Texas. This contact will take place on February 4.

2.. ARISS International Teleconference

The ARISS International Team held a teleconference on Tuesday, January 20.
Agenda items discussed included the next face-to-face meeting to be held in
the Netherlands in March, 2004, and the Expedition 9 crew change which may
adversely affect school contacts if Leroy Chiao is not licensed before his
launch. Also discussed was a Packet User Service Agreement, which would
provide ground based Ham radio operators with guidelines on how to use the
ISS packet radio equipment.

3.  Expedition 9 Commander May Obtain Amateur Radio License

Astronaut Leroy Chiao, who will be replacing William McArthur Jr., KC5ACR,
as commander of the Expedition 9 crew on the ISS, has expressed interest in
obtaining his Amateur Radio license. He will try to get through training
prior to the next Soyuz launch in April. His licensure and training are
critical to the continuation of the ARISS school contacts during the
Expedition 9 increment.

4. Phase 2 Radio System Engineering Checkout Passes

The ARISS team has been unable to schedule ISS Ham engineering passes for
the Kenwood radio system voice tests in early February due to the scheduled
Progress 13P docking and unpacking. The team is currently looking at the
weeks of February 16 - March 15 to schedule their tests. A procedure for the
tests has been written and will be uplinked to Mike Foale in the near

ARISS Chairman Frank Bauer and other members of the ARISS team met at GSFC
on Saturday, January 17. The team worked on getting the radio station,
NN1SS, set up for the engineering passes.

[ANS thanks Carol Jackson for the above information]


SB SAT @ AMSAT $ANS-039.04
Youngest Amateur Extra announces success via ARISS PBBS

AMSAT News Service Bulletin 039.04 From AMSAT HQ
SILVER SPRING, MD.  February 8, 2004
BID: $ANS-039.04

An Oregon girl considered a year ago as the youngest General class licensee
in the US now may be the country's youngest Amateur Extra ticket holder.
Seven-year-old Mattie Clauson, AD7BL (ex-KD7TYN and ex-KD7SDF), of Roseburg
passed her Extra examination January 14 during a Valley Amateur Radio Club
ARRL-VEC volunteer examination session in Eugene. The FCC granted her new
ticket and an Extra-appropriate call sign on January 20.

She announced her accomplishment in a message routed via the RS0ISS packet
system on the International Space Station. "Looks like a future astronaut to
me," Amateur Radio on the International Space Station (ARISS) Chairman Frank
Bauer, KA3HDO, remarked after spotting the post.

Mattie says she'd at least like to talk with one of the ISS astronauts some
day. She says she heard ISS Expedition 8 Commander Mike Foale, KB5UAC, on
the air from NA1SS but was unable to make contact. She keeps listening,
however. She's also a member of the ISS FanClub and enjoys digipeating
through RS0ISS.

[ANS thanks the ARRL for the above information]


SB SAT @ AMSAT $ANS-039.05
This Week's News in Brief

AMSAT News Service Bulletin 039.05 From AMSAT HQ
SILVER SPRING, MD.  February 8, 2004
BID: $ANS-039.05

**    The European Union will pay Russian space companies 121 million euros
(152 million dollars) to fund the launch of Russian Soyuz vessels from the
European Space Agency (ESA) launch complex in French Guiana .  --SpaceDaily

**   Hitching a ride on the same B-52 mother ship that once launched X-15
research aircraft in the 1960s, NASA's X-43A scramjet performed a captive
carry evaluation flight from Edwards Air Force Base, Calif., January 26. The
X-43 remained mated to the B-52 throughout this mission, intended to check
its readiness for launch as early as February 21.   --SpaceDaily

**   The countdown to the launch this month of Rosetta, a billion-dollar
comet-chasing spacecraft, is proceeding on schedule, the European Space
Agency (ESA) said here Thursday. Rosetta is due to be launched on February
26 from ESA's space base in Kourou, French Guiana, on a 10-year mission to
chase the comet Churyumov-Gerasimenko and land a laboratory probe on its
surface.  --SpaceDaily


In addition to regular membership, AMSAT-NA offers membership in the
President's Club. Members of the President's Club, as sustaining donors to
AMSAT Project Funds, will be eligible to receive additional benefits.
Application forms are available from the AMSAT-NA Office.

AMSAT-NA has developed an on-line volunteer survey, designed to
identify the interests and skills of those who may be available to directly
help in efforts to develop the amateur satellite program. The survey is
designed to be completed and returned on-line, and takes only a few minutes
to fill out.  To request the survey, simply send an e-mail request
to:volunteer at AMSAT.org

This weeks ANS Editor,
Lee McLamb, KU4OS, ku4os at AMSAT.org

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