[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][JAMSAT Home]

[jamsat-news:1901] ANS-081 AMSAT Weekly Bulletins


AMSAT NEWS SERVICE

ANS-081

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.

Please send any amateur satellite news or reports to:
ans-editor@amsat.org


In this edition:
*  NO-45/Sapphire Update
*  OSCAR-11 REPORT   16 March 2004
*  ARISS Status and Contact Schedule
*  Los Alamos and Surrey Satellite Contract for Experiment
*  Steam micro-propulsion demonstrated in-orbit
*  This Week's News in Brief


SB SAT @ AMSAT $ANS-081.01
NO-45/Sapphire Update

AMSAT News Service Bulletin 081.01 From AMSAT HQ
SILVER SPRING, MD.  March 21, 2004
To All RADIO AMATEURS
BID: $ANS-081.01

The NO-45 digipeater remains on.  User are requested NOT
to use the Bulletin Board. When the Bulletin Board is used it effectively
"locks out" ground access to the spacecraft CPU.

Everyone is  welcome to use the digipeating/APRS features of Sapphire,
callsign KE6QMD, as per the user service agreement located at the following
URL
http://web.usna.navy.mil/~bruninga/pcsat/contract.txt

There will be occasional dropouts caused by the CW beacon, and Users are
advised to expect extra packet chatter during West Coast (USA) passes, as
some schools are using Sapphire for operations training.

[ANS thanks Mike, KE6YNJ for the above information]

/EX


SB SAT @ AMSAT $ANS-081.02
OSCAR-11 REPORT   16 March 2004

AMSAT News Service Bulletin 081.02 From AMSAT HQ
SILVER SPRING, MD.  March 21, 2004
To All RADIO AMATEURS
BID: $ANS-081.02

OSCAR-11 celebrated its 20th birthday on 01 March. After 20 years in orbit,
it is still transmitting useful data.  To commemorate this event, AMSAT-UK
is issuing a special QSL for reports of reception during March. There are
special endorsements for hearing the satellite on it's birthday, and for
mode-S reception.  It's still not too late to apply for a QSL, but all
reception reports must be received by 07 April. For full details visit the
AMSAT-UK website at http://www.uk.amsat.org/

At the present time the satellite is operating in a default mode,
transmitting continuous ASCII telemetry on 145.826 MHz., for ten days
followed by ten days of silence.  However, during March ground control are
hoping to reset the timer each time the VHF beacon switches OFF.  This
should minimize the OFF time, but there may be some gaps in the
transmissions.  The mode-S beacon is ON continuously.

For the latest news, visit the website   http://users.zetnet.co.uk/clivew

During the period 16 February to 15 March 2004 the 145.826 MHz. beacon has
been heard transmitting continuous ASCII telemetry from 25 February to 06
March, and from 09 March.  If the current ten day cycle continues, the
beacon should switch OFF on around 19 March. During this period good
signals have been received.

Around 27 February the date in the ASCII telemetry incremented, giving an
error of four days.  This appears to be a leap year problem, which first
occurred in 1992.

The internal temperatures have increased by about 1.5C. They are now 14.6C,
11.8C and 17.8C for battery, telemetry electronics and command decoder,
respectively. Solar eclipse predictions indicate that temperatures are
expected to increase, reaching a peak in March, a trough in June/July and
then increasing until the end of September, when the satellite will
encounter continuous sunlight for the remainder of the year. Higher
temperatures and greater temperature changes are expected this year,
compared to 2003.

The battery voltage observed during daylight passes has decreased.  This is
because the S-band beacon was switched OFF during the previous reporting
period. The reduction in line current causing higher than usual battery
voltage. Observations have varied between 13.2 and 13.5 volts, with an
average value of 13.35 volts for 25 February to 06 March.  From 09 to 15
March the voltage varied from 13.6 to 13.7 with an average value of 13.6
volts.

Spin periods of 344 to 453 seconds have been measured from the magnetometer
telemetry. The rotational speed is nominal and variations random. The
direction of rotation is normal.

Users of OSCAR-11 should note that the date in the telemetry is now
advanced by FOUR days.  The time is advanced by 19.5 minutes, and this
error is increasing by about one minute per year.

The mode-S beacon on 2401.5 MHz. has been heard by Ferrucio IW1AM, Dean
AL7CR, Mark CT1JFC/G4MAW, Ken W7KKE, Ferracio & Piero IW1AM/IZ1ERR, Martin
G7MRF, Mirek OK2AQK and Bill GM0ICF.  Also, many more reports have been
submitted to the AMSAT-UK website for the special birthday QSL endorsement.
Many thanks for all those reports.

The mode-S beacon is ON continuously, even when the VHF beacon is
OFF, nominally transmitting an unmodulated carrier on 2401.5 MHz.
There is however a VERY low level of AFSK modulation, (now a constant
audio tone), which has been detected on strong signals.
Telemetry indicates that the beacon has partially failed, and is
delivering half power.  This beacon is a useful test source for those
testing mode-S converters, as an alternative to OSCAR-40. However the
signals are very weak, and there is a lot of Doppler. Users should
also note that the polarization of OSCAR-11 is LHC. Even if you can't
hear OSCAR-11, your equipment may still be OK for OSCAR-40. Any
reports of reception on 2401.5 MHz. would be most welcome.  Please
e-mail g3cwv@amsat.org.

The 435.025 MHz. beacon is normally OFF.  It can only be heard on the
very rare occasions when the satellite is being commanded by ground
control, i.e.. within range of Guildford, UK.  When the 435 MHz beacon is
transmitting, the 145 MHz beacon is normally OFF.  The data transmitted
is mainly binary.

The web site contains details about using a soundcard for data
capture, and also details about using hardware demodulators. There is
software for capturing data, and decoding ASCII telemetry.
There is an archive of raw data for analysis, which is continually
being expanded, as new data is captured.  Originally this was for
WOD, but it is now being expanded to include ASCII telemetry. At the
present time the telemetry covers 1996 to April 2003.  I will add
other years as time permits.  In parallel there is a news archive
which provides an overview of the state of the satellite, at the
times when the telemetry was captured.

If anyone out there can provide any data, particularly for the 1984
to 1993 years, this would be most appreciated.  Please e-mail me
with details.  However please DO NOT SEND ANY FILES, before further
discussion.

Also included are some audio files, examples of each type of data
transmitted by OSCAR-11, each one plays for about ten seconds.  There
are also examples of mode-S reception.  All the audio files are
zipped, so that they can be played off-line.  These should help
listeners identify the various types of data, and give an indication
of the signal quality required for successful decoding.

The URL is -

      http://www.users.zetnet.co.uk/clivew/

If you place this bulletin on a terrestrial packet network, please
use the bulletin identifier $BID:U2RPT95.CWV, to prevent duplication.

[ANS thanks Clive, G3CWV  for the above information]

/EX


SB SAT @ AMSAT $ANS-081.03
ARISS Status and Contact Schedule

AMSAT News Service Bulletin 081.03 From AMSAT HQ
SILVER SPRING, MD.  March 21, 2004
To All RADIO AMATEURS
BID: $ANS-081.03

The ARISS packet uplink is back on 145.99 with a downlink of 145.80.
APRS/packet is normally on but usually off for awhile after a school
contact.  Random voice contacts are rare due to limited
time from the 2 man crew.

To provide some insight on how tough it is to schedule contacts, here are
some of the constraints the ARISS mentors must work under:
Each Increment is 26 weeks in length.
For the next increment we may not schedule:
1. Anything the first 4 weeks.
2. During EVA weeks (2 EVAs are scheduled for Increment 9)
3. at least 2 weeks prior to the Increment change.
4. no contacts during meal and exercise periods.
5. no contacts during post-sleep and pre sleep (before 0800 UTC and
after1930 UTC)

Recent School Contacts:

School of Bhac, Scotland
Contact was successful Wednesday 2004-03-17 14:26 UTC telebridge via WH6PN

Congratulations to Mike and the School of Bhac!  Thanks to WH6PN for the
ARISS telebridge ground station, to KC6ROL acting as MC, and to MCI for the
telebridge facilities and webcast.

Upcoming School Contacts:
Saltoschool Hanevoet, Eindhoven,NL-5655 CP, direct via PI4EHV
DELTA mission with AndrKuipers
TBD 2004-04-24

ESA-ESTEC, Noordwijk, NL-2201, direct via PI9ESA
DELTA mission with AndrKuipers
TBD 2004-04-25

Currently the ARISS operations team has a list of over 60 schools that we
hope will be able to have a contact during 2004.   As the schedule becomes
more solidified, we will be letting everyone know.  Current plans call for
an average of one scheduled school contact per week.

[ANS thanks Charlie, AJ9N and Kenneth, N5VHO for the above information]

/EX

SB SAT @ AMSAT $ANS-081.04
Los Alamos and Surrey Satellite Contract for Experiment

AMSAT News Service Bulletin 081.04 From AMSAT HQ
SILVER SPRING, MD.  March 21, 2004
To All RADIO AMATEURS
BID: $ANS-081.04

Los Alamos National Laboratory and Surrey Satellite Technology Limited
(SSTL) have announced a contract agreement for development of an advanced
satellite platform for ionospheric and lightning studies.

The British firm, SSTL, will create the satellite platform that will be used
to carry the Cibola Flight Experiment payload developed by Los Alamos. The
contract with SSTL is valued at USD 11.8 million.

Los Alamos, operated by the University of California for the U.S. National
Nuclear Security Administration, is building the Cibola Flight Experiment
(CFE), a reconfigurable processor payload intended for a low-Earth orbit
system. It will survey portions of the VHF and UHF radio spectra. The
experiment uses networks of reprogrammable, field programmable gate arrays
(FPGAs) to process the received signals for ionospheric and lightning
studies. The objective is to detect and measure impulsive events that occur
in a complex background.

The experiment will also validate the on-orbit use of commercial,
reconfigurable FPGA technology demonstrating several different schemes for
the mitigation and correction of "single-event upsets" that would crash most
current computer systems.

The U.S. Department of Defense Space Test Program (STP) is including the CFE
satellite as part of the STP-1 space flight mission. The STP-1 mission goal
is to provide space-flight opportunity for a maximum number of DoD Space
Experiments Review Board payloads on a single launch. The DoD Space Test
Program is responsible for the integration of seven satellites into a single
payload stack and launch of the STP-1 mission. The STP-1 mission is
scheduled for launch in 2006 on a medium-class Lockheed-Martin Atlas-V, a
U.S. Air Force Evolved Expendable Launch Vehicle (EELV), using the EELV's
Secondary Payload Adapter that allows small satellites to be launched as
"piggyback" passengers with larger spacecraft.

Timothy Murphy, head of research and development during the selection
process in the International, Space and Technology Division at Los Alamos,
added "It will be essential that our payload's partners can meet our
schedule with a flight-proven satellite platform that we are confident will
be flight-ready in time for the EELV launch."

[ANS thanks SSTL for the above information]

/EX


SB SAT @ AMSAT $ANS-081.05
Steam micro-propulsion demonstrated in-orbit

AMSAT News Service Bulletin 081.05 From AMSAT HQ
SILVER SPRING, MD.  March 21, 2004
To All RADIO AMATEURS
BID: $ANS-081.05

SSTL has demonstrated in-orbit the use of a steam propulsion system onboard
the UK-DMC satellite, launched on 27th September 2003. The novel
micro-propulsion experiment used 2.06 grams of water as propellant. This
'green' propellant is non-toxic, non-hazardous to ground operators and
results in improved specific impulse over conventional cold gas nitrogen, at
a significantly lower cost.

During the first in-orbit firing, the thruster was pre-heated to 200
degrees. Pre-heating ensures that no liquid phase water is ejected, only
steam. The spacecraft experienced 3.3 milliNewtons of thrust over a 30
second period.

Designed and built in-house at SSTL, the miniature resistojet, weighing 13
grams, uses just 3 Watts of power to heat the propellant, emitting steam
through a conventional rocket nozzle to generate thrust. The hotter the
propellant, the higher specific impulse performance achieved.

The experiment has demonstrated that:

* Water can be used as a spacecraft propellant giving a safe, low cost
solution, without performance loss over conventional cold gas nitrogen
systems.

* Low thrust micro-propulsion can achieve milliNewton thrust levels - a
useful range for nanosatellites (< 10 kg mass) and low cost CubeSats.

* A low cost micropropulsion system has been developed and flown in just 8
months.

[ANS thanks SSTL for the above information]

/EX

SB SAT @ AMSAT $ANS-081.06
This Week's News in Brief

AMSAT News Service Bulletin 081.06 From AMSAT HQ
SILVER SPRING, MD.  March 21, 2004
To All RADIO AMATEURS
BID: $ANS-081.06

**       FCC's Notice of Proposed Rule Making Broadband
over Power Lines -- ET Docket 03-104 -- has been published in the Federal
Register.  This starts the clock on the comment deadline. Comments are due
by May by 3rd.  Reply comments due by June 1. Comments may be filed
electronically via the FCC's Electronic Comment  Filing System at
http://gullfoss2.fcc.gov/ecfs/upload  --Newsline

**   Physicists in New Zealand have shown that last November's
record-breaking solar explosion was much larger than previously estimated,
thanks to innovative research using the upper atmosphere as a gigantic x-ray
detector.  Before the storm peaked, x-rays overloaded the detectors on the
Geostationary Operational Environmental Satellites (GOES), forcing
scientists to estimate the flare's size. Taking a different route,
researchers from the University of Otago used radio wave-based measurements
of the x-rays' effects on the Earth's upper atmosphere to revise the flare's
size from a merely huge X28 to a "whopping" X45, say researchers Neil
Thomson, Craig Rodger, and Richard Dowden .--SpaceDaily

**     A small near-Earth asteroid (NEA), discovered Monday night by the
NASA-funded LINEAR asteroid survey, made the closest approach to Earth ever
recorded. There was no danger of a collision with the Earth during this
encounter.  The object, designated 2004 FH, is roughly 30 meters (100 feet)
in diameter and passed just 43,000 km (26,500 miles, or about 3.4 Earth
diameters) above the Earth's surface on March 18th at 22:08
UTC. --SpaceDaily

/EX


In addition to regular membership, AMSAT 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 Office.

AMSAT 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

73,
This weeks ANS Editor,
Lee McLamb, KU4OS, ku4os at AMSAT.org

----
Via the ans mailing list at AMSAT.ORG courtesy of AMSAT-NA.
To unsubscribe, send "unsubscribe ans" to Majordomo@amsat.org