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[jamsat-news:1382] * SpaceNews 04-Dec-00 *

* SpaceNews 04-Dec-00 *

BID: $SPC1204



For the past month or so, TiungSat has been operating with a 9600bd downlink
on 437.325 MHz.  Late last week, controllers switched over to a data rate
of 38k4 when the satellite was over Kuala Lumpur.  TiungSat is now operating
at 38k4 with the downlink normally off.  Data recovery at 38k4 is extremely
good with efficiency for most of the pass running around 100%.

The satellite is using the high power transmitter with an output power of
around 8W and this should provide a very good 38k4 downlink.  The downside
of this is that with this transmitter operating, the power budget is
negative so we can't support permanent operations.  This therefore requires
the groundstation to switch the downlink on when the satellite comes in
range using the method first used for UO-36.  The way this works is for the
groundstation software to send a request to the spacecraft to switch the
downlink on.  The spacecraft receives this request and checks the battery
voltage to see if it can support the operation, and if it can it will
activate the downlink.  It is not anticipated that there should be any
periods where the downlink is not available due to power limitations as
is the case with UO-36.

To enable this downlink switching under WiSP you must add a value to the
registry by following these steps -:

Open the key HKEY_LOCAL_MACHINE\SOFTWARE\WiSP\Satellites\TiungSat
Right mouse click on the right window in REGEDIT and select NEW->DWORD Value
Enter the name as "Tx Request"
Set the value to 1.

As this issue was going to press, there were some difficulties reported
in placing the satellite in 38k4 mode.  Controllers have asked that
groundstations do NOT enable the 38k4 downlink unless they are indeed
equipped to receive the downlink at the high-speed data rate.

Chris G7UPN / ZL2TPO
Kuala Lumpur, Malaysia

With all the recent interest in shipping AO-40 telemetry frames over
the Internet, Phil Karn, KA9Q, has put together an initial proposal
for a standard protocol to do this.  Phil is calling it the Spacecraft
Telemetry Protocol (STP), as he is am trying to make it general enough
to use with any spacecraft, not just AO-40.

The idea is to add a standardized header to each telemetry frame that,
as a minimum, identifies the satellite and telemetry format, and gives
the length of the frame.  Optional headers can be added to identify the
receiving station and/or receiving location, the received date/time,
frequency, and receiver Eb/No (digital SNR).  Other optional headers
can be added.  The format is patterned after HTTP, the application
protocol used by the World Wide Web.

STP can be sent using either TCP or UDP.  If UDP is used, the Internet
Multicast Backbone can also be used.  This is an excellent mechanism
for the dissemination of real-time data over the Internet, and it is
well supported under Linux and other operating systems.  But other,
more ad-hoc multicast mechanisms could be used as well, such as IRC.

The URL for Phil's spec is:


Comments are welcome.

[Info via Phil Karn, KA9Q]

Bill, K7MT reports that over the recent Thanksgiving Holiday, he and
his brother in law Mike Pendly, K5ATM, from New Mexico ventured to Grid
Squares unknown.  Together they worked 68 stations on UO-14 with an arrow
antenna and Kenwood dual bander from Montana/North Dakota Grids DN88, DN87,
DN86, DN78, DN77, and DN76.  They had a blast although Bill admits that
when Mike worked Randy N7SFI, UO-14 was at 14 degrees AZ, 14 degrees EL,
and the temperature was 14 degrees F.  It was rather chilly for a ham from
New Mexico to be in Montana during the month of November.  On the way back
to New Mexico, Mike stopped in Grid DN75 for N7SFI so Randy could fill
in those rare Montana Grids.

[Info via Bill Erhardt, K7MT]

The SUNSAT team has been working with Steve Dimse to integrate the APRS WX
packets coming from the STANFORD APRS weather station in Antarctica into
the APRServe system.  The WX station's callsign is KE6JAB-1.  It should
also be on FINDU.com.  This effort should be regarded as only the beginning
of a worldwide APRS Satellite system.  Although this first permanent station
is a WX station, that is not its main purpose.  The APRS satellites will
be for anyone far distant from the existing APRS VHF network who need to
get a remote position/status packet into the system.

[Info via Bob Bruninga, WB4APR]

Randy Shriver, KG3N, of Hanover Pennsylvania has made the very first contact
with Bill Shepherd, KD5GSL, onboard the International Space Station directly
after the engineering tests were completed.  The contact took place on
November 13, 2000 at 5:54am. 

Text of contact between KG3N in Pennsylvania and KD5GSL on Space Station
Alphai follows:

KG3N: KD5GSL from Kilo Golf 3 November.

KD5GSL: Kilo Golf 3 November, KD5GSL -- go.

KG3N: Okay. Thanks for returning my call. The name is Randy and I'm
      in Pennsylvania.

KD5GSL: Well Randy, you are my first contact from space station. 

KG3N: OK. Thanks for the contact. You are just going below my horizon.

This is KG3N, clear.

To hear the contact, please check Newsline #1216 Dated December 2, 2000 at:


[Info via Randy Shriver, KG3N]

The following is the latest FO-29 operating schedule:

Nov.27 - Dec.15    Mode JA
Dec.16 - Dec.24    Mode JD 1200 bps PSK mailbox
Dec.25 - Jan. 7    Mode JA

[Info via Kazu Sakamoto, JJ1WTK]

Thanks to all who recently sent news items and messages of appreciation to
SpaceNews, especially:


Comments and input for SpaceNews should be directed to the editor
(John, KD2BD) via any of the paths listed below:
WWW:        http://www.njin.net/~magliaco/
MAIL:       John A. Magliacane, KD2BD
            Department of Engineering and Technology
            Brookdale Community College
            765 Newman Springs Road
            Lincroft, New Jersey 07738
INTERNET:   kd2bd@amsat.org, magliaco@email.njin.net

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