The Radio Amateur Satellite Corporation, Inc. (AMSAT), a non-profit
501c3 organization in the U.S. which designs, builds, launches
satellites for the use of radio amateurs worldwide is holding its
annual meeting in Pittsburgh, Pa. this coming weekend.
As with all amateur radio endeavors of any significance, a lot
happens as a result of holding these meetings, and usually in the last
hours before the event. This one is no different but I take the time
to write to you because of some significant things that will happen at
The following well known amateurs will attend in addition to the usual
list of AMSAT suspects.
Frank Brickle, AB2KT
Designer and co-author of DttSP, the software core used in PowerSDR
(Flex-Radio), uwSDR (http://uwsdr.berlios.de) , jSDR, DttSP-shell,
and several others. Designer and author of the VR, a radio kernel to
be used in software/cognitive efforts for robust distributed computing
radio systems and recently described at the DCC. Contributor to
GnuRadio and HPSDR. For a general introduction to the entire area
Phil Covington, N8VB
Designer, author, leading developer in the HPSDR offerings
(http://hpsdr.org) including Atlas, Ozymandias with contributions to
Janus, Mercury, Penelope, and more.
Matt Ettus, N2MJI
GnuRadio. Design of USRP and USRP2 for GnuRadio. And lead designer
on the AMSAT Advanced Communications Package.
Hartmut Päsler DL1YDD (AMSAT-DL V.P.)
Hartmut will be telling us of the current status of Phase 3E and their
launch opportunities and about Bochum 66' Dish that has been used to
receive signals from planetary probes.
Bruce Perens K6BP
formerly of Pixar and amongst other things, editor of the Bruce Perens
Open Source series of books.
Gerald Youngblood, K5SDR
Owner of Flex-Radio, designer of the SDR-1000, Flex5000
CONTRIBUTOR OF A MAJOR SYMPOSIUM PRIZE!!
At this meeting AMSAT-NA will announce a major new satellite
opportunity for us and how we intend to take advantage of it if all
the stars line up! President Rick Hambly, W2GPS, has been working
nonstop on this and we are excited to tell you about it in the first
level of detail we are able to give and how we will be proceeding.
We have an international audience attending and the symposium agenda
is available from the URL above and many great speakers. Ya'll come.
I realize that this is the last minute but more than a little bit of
this stuff happened in the LAST TWO WEEKS and until it was ready to
release, we just couldn't. I am hoping to reach amateurs who are
within driving distance of Pittsburgh or those who can decide at the
last minute to come. I believe this is an AMSAT symposium you do not
want to miss.
22 October 2007
During the period 27 September to 22 October 2007 the satellite has been
heard from 06 October to 08 October. The beacon switched on as expected, on
06 October, but prematurely switched OFF sometime between 08 and 09
October. Signals were weaker than usual.
The on-board clock has continued to loose time. During the ten day OFF
period it lost 72 minutes, and there was a further loss of 48 minutes
during the last ON period. When last heard the clock error was 69.97793
days slow. The day of the week counter is unchanged with 0 representing
The premature shutdown has probably caused the watchdog timer to reset,
and start a new 20 day cycle. If that has occurred then the beacon should
resume transmissions around 29 October 2007.
I am indebted to John N7ZL, John N3NKC, Thomas HB9SKA, and Peter ZL3TC, for
their reports. Many thanks.
The satellite is now in continuous sunlight and this will continue until
the start of November, when there will be a short eclipse season, lasting
until around 07 January. However the maximum duration of the eclipses will
only be about 12 ninutes. At this level the satelite might just survive.
John KD2BD has noticed a descrepancy between my eclipse predictions and
those from his Predict program. This could explain why the beacon didn't
switch on until mid September. The main cause of the problem was due to
the use of old Keplerian elements. In previous years the it had been
possible to use elements which were many months out of date, with only
minor effects on the eclipse predictions. This year the orbit appears to
be more critical. Different software also produces slightly different
results. Many thanks John for your comments.
The current status of the satellite, is that all the analogue telemetry
channels, 0 to 59 are zero, ie they have failed. The status channels 60 to
67 are still working. The real time clock is showing a large accumulated
error, although over short periods timekeeping is accurate to a few
seconds per month. The day of the month has a bit stuck at 'one' so the
day of the month may show an error of +40 days for some dates. The time
display has switched into 12 hour mode. Unfortunately, there is no AM/PM
indicator, since the time display format was designed for 24 hour mode.
More data is required to determine exactly when the date changes.
The spacecraft computer and active attitude control system have switched
OFF, ie. the satellite' attitude is controlled only by the passive gravity
boom gradient, and the satellite is free to spin at any speed. When
telemetry was last received it showed that one of the solar arrays had
failed, and there was a large unexplained current drain on the main 14 volt
bus. After 23 years in orbit the battery has undergone around 100,000
partial charge/discharge cycles, and observations suggest that it cannot
power the satellite during eclipses, or sometimes during periods of poor
The watchdog timer now operates on a 20 day cycle. The ON/OFF times have
tended to be very consistent. The average of many observations show this to
be 20.7 days, ie. 10.3 days ON followed by 10.4 days OFF. However, poor
solar attitude may result may result in a low 14 volt line supply, which
may cause the beacon to switch OFF prematurely, and reset the watchdog
timer cycle. When this occurs, the beacon is OFF for 20.7 days.
The Beacon frequencies are -
VHF 145.826 MHz. AFSK FM ASCII Telemetry
UHF 435.025 MHz. OFF
S-band 2401.5 MHz. OFF
Listeners to OSCAR-11 may be interested in visiting my website. If you need
to know what OSCAR-11 should sound like, there is a short audio clip for
you to hear. There is an example of the latest telemetry received from the
satellite. The website contains an archive of news & telemetry data. It
also contains details about using a soundcard or hardware demodulators for
data capture. There is software for capturing data, and decoding ASCII
telemetry. The URL is www.users.zetnet.co.uk/clivew/
If you place this bulletin on a terrestrial packet network, please
use the bulletin identifier $BID:U2RPT138.CWV, to prevent duplication.
73 Clive G3CWV xxxxx(a)amsat.org (please replace xxxxx by g3cwv)
This information may be useful for those who do not read the ANS Bulletins.
SB SAT @ AMSAT $ANS-294.01
AMSAT-NA Space Symposium Begins This Week
AMSAT News Service Bulletin 294.01
From AMSAT HQ SILVER SPRING, MD.
October 21, 2007
To All RADIO AMATEURS
The AMSAT-NA 2007 Space Symposium will begin this week! The AMSAT
Board of Director's meeting on Thursday, October 25 kicks off the
event. Symposium activities begin on Friday, October, 26. Amateur
Radio Satellite Operators will find the AMSAT Space Symposium to be
an exciting and rewarding event-filled weekend. Here are some of the
features and events to look forward to:
+ AMSAT-NA Annual General Meeting - Saturday, October 27, 11:00AM
Eastern Daylight Time (UTC-4). This meeting will be on the AMSAT
conference on EchoLink.
+ AMSAT-NA Board of Directors Meeting
+ AMSAT Directors and Officers will be available to answer
+ AMSAT Annual Banquet with Keynote Speaker
+ Technical forums focusing on the latest planning and technology of
Amateur Radio in Space
+ All Papers and Presentations will be published in the Symposium
Proceedings for all registered attendees
+ Technical demonstrations of prototype flight hardware and software
for AMSAT Eagle - the next generation in space
+ Discussions and demonstrations of SuitSat-2, ARISS, solid state
RF power amp, antennas, AO-51
+ Update on AMSAT's new Maryland Lab
+ AMSAT Area Coordinators' Breakfast and Meeting on Sunday Morning
+ IARU Satellite Forum
+ President's Club Reception
+ Satellite Beginner's Session: Introduction to Satellites
+ An operating satellite station capable of working AO-7, FO-29,
AO-27, SO-50, AO-51 and VO-52
+ N2SPI satellite antenna demonstrations and antenna construction
+ Meet and greet old friends and make new friends
+ Enjoy eyeball QSOs with satellite designers, builders, and operators
from around the world
+ Sunday afternoon tour to the WPXI-DT Digital Studio
The AMSAT Software Defined Transponder Team is working toward having
an operational VHF - UHF transponder available for the entire weekend.
Eagle Project Team members will be available to answer your questions
and provide demonstrations.
AMSAT-DL Vice-President and Board member Hartmut Päsler, DL1YDD will
give a presentation about the current status of the P3-E project and
The full Symposium schedule has been posted on the web pages.
Talk-in for Symposium will be on 146.955/146.355 or 443.65/448.65
repeaters. Both repeaters use 131.8 Hz CTCSS.
New to the Symposium this year is a selection of apparel that may be
ordered. We have Symposium themed golf shirts, tee shirts, key rings
ball caps. A percentage of these sales will go to Eagle.
If you haven't registered yet you may do so at the Symposium site.
[ANS thanks 2007 AMSAT Space Symposium Co-chairs Kevin N3HKQ,
and Pat KC4WTT for the above information]
I've been trying to come up with an easy GO-32 pass-time
predictor for the mobile. This morning I got it! The Ground
track of GO-32 repeats every 10 days!
So All you need on your dash board is this strip of paper.
Day1 Day2 Day3 Day4 Day5 Day6 Day7 Day8 Day9 Day1
---- ---- ---- ---- ---- ---- ---- ---- ---- ----
0930 0910 1025 1005 0940 0920 1040 1015 0950 0930
2050 2030 2005 2125 2100 2040 2015 2135 2110 2050
2210 2145 2155
For example, today is Day3 in Wash DC.
If you print these in fixed font, it will show you the pass
times for any day and time zone and location, as long as you
know what day sequence to be on in your area. And we can have
GO-32 send down a table-of-days in its bulletins! So if you
ever hear GO32 once, then you will have all you need for
tracking for the next few months or so for your area!
Initially, I assumed this table would be only for Washington DC
(77 deg Longitude) and 40 deg latitude where I calculated it.
But it should also apply anywhere at this longitude north or
south and be off by less than 5 minutes or so.
Then I thought we would need a different one for every 5 degrees
of longitude... But then realized that just as the pattern
repeats every 10 days in time, it also repeats incrementally in
longitude! Since the longitude increment of GO-32 is about 26
degrees, that means these multiples of 26 degrees from
Washington DC will have the same pattern on the same day as we
do. And that every 2.6 degrees in between will have an
additional day offset from ours.
Wow, it can't get any simpler than that for mobiles to know when
to use their rigs on GO-32 when traveling in wilderness areas.
A similar table could be predicted for ECHO (AO-51) maybe.
ELEVATION ANGLE: To keep the chart simple, I did not include
max elevations, but that can be added in the final version. It
is also easy to infer. The days with double passes are near 30
degrees each (barely detectible by the mobile) The days midway
between these lowest peak passes are the highest elevations (75
or more degrees). And you can interpolate inbetween these.
UPLINKS! The above table gives you only the BEST pass of the
day for your location (passes above 30 degrees). This is the
pass where you can expecet to receive the GO32 downlink on your
mobile whip antenna. HOWEVER, every day, there is a pass
exactly 100 minutes before and after each of those passes too.
So now you have 6 chances a day to report your position in the
wilderness and 2 chances a day to receive any APRS message
Happy wilderness traveling!
(Oh, and of course, make sure there is someone in your footprint
that is SATgating your data into the APRS system so that your
position and status and any emails get delivered.)...
I am posting this for Bart, see below:
FS: Fukuyama MUV-430A, 144 MHz to 432-MHz 10-watt transverter. Has
cross band mode for Satellite operation. 3 watts VHF drive for 10
watts UHF out. Replaced by a multi-band transceiver, so now spare to
my needs. $95 + shipping
73, Bart W9JJ
Not yet, although the telemetry transmitter is running on 435.150. We are working on it every pass though, and hope to have it back running soon.
73, Drew KO4MA
>Sent: Oct 22, 2007 12:27 PM
>Subject: [ao51-modes] AO51 web page request
>Is AO51 back on line yet?
>Via the AO51-modes mailing list courtesy of AMSAT-NA
Nice to hear from you. I also have been missing from the birds for some time but I did listen for AO-07 yesterday morning and this morning and heard nothing. Something has happened here to give me an S9 noise level on 10M so I can't tell if there is anything on mode A or not but I did not hear anything on mode B. VO-52 was good yesterday and today so I think I am receiving OK.
I don't know whee all the other reports went but they seem to be missing this week end.
73 de Jess - W4MVB
I have a pair of Icom preamps for sale, one AG-35 70cm preamp and one AG-25
2m preamp. Both work, although are they are well weathered. You'll need to
supply your own new U-bolt. New price on these is currently about $160 each
I think. I will sell either for $80 shipped, or the pair for $150 shipped
(shipping via USPS Priority Mail in the US only, outside US will pay the
difference please). Paypal is the preferred payment method. I can also
deliver to Symposium in Pittsburgh this week.
73, Drew KO4MA