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SSETI Express Launch Campaign update and LEOPS information



The current status of the launch programme can be seen at 
http://sseti.gte.tuwien.ac.at/WSW4/MOPWS/news.php

The latest version of the LEOPS information sheet is appended below - its 
primary audience is "non amateur" so please do not be upset by some of the 
basic information and advice that it contains!

73 de Graham
UA/G3VZV

SSETI Express LEOPS (Launch & Early Operations) Info


These are the preliminary TLEs for SSETI Express based upon a launch at 
06:52:26 UTC on September 27th 2005

They will probably be updated just before launch and will certainly only 
work for a couple of days after launch. By then we should have received 
updates from NORAD and can then start to identify which orbit data refers to 
which satellite.

For the first few orbits they will also be valid for the cubesats and all 
the other payloads on the same launch. These are detailed below.

SSETI1
1 288XXU 0503XC   05270.28641000 -.00000001  00000-0  10000-4 0    12
2 288XX  98.1900 167.4100 0001920   0.0000  50.5000 14.60850000 00013

This data can be entered into any of the normal "tracking/prediction" 
programmes for display at launch events.

SSETI Express UHF transmitter will be activated approximately 100 minutes 
after launch. The details below give some information about what we expect 
to hear and when for Express and the cubesats.

To receive the UHF transmissions from Express and the cubesats there are two 
possibilities.

The simple possibility is a handheld receiver and simple hand held TV type 
yagi antenna which is pointed in the general expected direction. When 
Express is heard then this will only be obvious by a sudden burst of 
increased noise from the loudspeaker. - the 9k6 data sounds just like noise 
to the human ear! This will not be very impressive to invited guests but
will make the Express teams themselves very happy. Remember to have three 
frequencies stored in the radio 437.260MHz at AOS, 437.250MHz for when the 
satellite is at its nearest point to you and 437.240MHz as it moves away 
from you. This is Mr Doppler at work.

The more complicated possibility is to use a "proper" receiving station with 
automatically steered circularly polarised antennas, a mast head preamp, 
Doppler adjusted UHF radio with a widened IF to pass the 9k6 data and a 
suitable TNC feeding a computer and display. With this set-up it should be 
possible to display the decoded telemetry from the satellite.

There is already a satellite in a very similar orbit using similar 
frequencies and modulation method to Express. This is called AO51 (Amsat 
Oscar 51) also known on some databases as Echo. It is strongly recommended 
that you use the signals from this satellite to test your receive system 
(simple or complicated options) so you have already had experience before 
the launch day and demonstration. AO51 has a variety of scheduled activity 
modes and frequencies and these can be checked here 
http://www.amsat.org/amsat-new/echo/ControlTeam.php Most times it is 
radiating a voice signal and a 9k6 data signal simultaneously.


SSETI Express

Downlink: 437.250MHz AX25 9k6 FSK

(also 2401.835MHz 38k4 data and voice - but not for initial operations)

The first transmission will occur approximately 65 min after separation from 
the launch adaptor- approx 100 mins after launch - we now expect this now to 
occur around 08:32 UTC when Express is over northern Europe.

The type of the first transmissions will depend on the state of the battery.

In Nominal mode - a sub 1 second burst of AX25 telemetry every 18 seconds.

In Recovery or Safe mode - simple on/off telemetry comprising 16 x 100msec 
carrier pulses. This telemetry is repeated every 30 seconds in Safe Mode and 
every 2 mins when in Recovery Mode.

The satellite will transmit at a power of 3 watts.

The next time that Express can be heard over Europe will be the pass that 
starts in Aalborg at around 10:03 UTC. This pass gives good coverage of all 
of Europe and should also be audible from the launch site.

Reception reports will be welcome by email at operations@sseti.net or by 
placing them on the SSETI Newsgroup at slave.gte.tuwein.ac.at in the folder 
"sseti.express.report" where you will also be able to see reports from other
locations around the world.

Full information on receiving SSETI Express signals, decoding the telemetry, 
submitting it to the project team and entering the competition will be 
posted at  http://sseti.gte.tuwien.ac.at/WSW4/MOPWS/news.php This will have 
links to all the updated pages as they occur.


NCUBE2: a cubesat which will be released by Express

Downlink: 437,305MHz
Bitrate: 9600b/s
Modulation technique: GMSK

The first transmission will occur 20 min after separation from Express - 
approx 120 mins after launch.

The message: "DE=LA1CUB=NCUBE2=FF=LA1CUB===" is morsed using a 2400Hz tone, 
26 words per minute where FF is a hex number [00=3,0V - FF=4,5V]
        If battery voltage is above 3,8V, every 2 minutes
        If battery voltage is below 3,8, every 5 minutes

At the end of the message an unnumbered AX.25 packet is attached containing 
the string:

DE=LA1CUB=NCUBE2=NORWEGIAN CUBESAT - WWW.NCUBE.NO

In the header of the AX.25: Callsign: NCUBE  Destination: EARTH

The satellite will transmit at a power of 1,5W at full battery charge

Reception reports will be welcome email to ncube@rocketrange.no  or by phone 
+47 76 14 44 00


UWE 1: a cubesat which will be released by Express

Downlink 437,505MHz. 9k6 FSK AX25 packet

The first transmission will occur 6 min after separation from Express - 
approx 106 mins after launch.

The satellite will transmit for about 1 sec every 1 minute. The output power 
of the transceiver is approx 1 watt.

Further details will be made available later.

Reception reports will be very welcome at 
cubesat@informatik.uni-wuerzburg.de.


Cubesat Xi-V: a cubesat which will be released by Express

CW signal on 437.465MHz
FM packet of AFSK AX.25 on 437.345MHz

The first CW transmission will occur 30 min after separation from Express - 
approx 130 mins after launch.

FM packet will not be transmitted unless commanded by the ground station.

The interval of the CW signal is about 30 seconds.

The output of CW signal is 80mW, and that of FM packet is 800mW.

Both signals share one dipole antenna, so the satellite cannot transmit both 
signals at the same time.

The email address to receive reports will be announced at the ground station 
web page http://gs.space.t.u-tokyo.ac.jp/  before launch.


SAFIR-S

A module integrated within the RUBIN experimental payload which will stay 
attached to the launch adaptor.

A frequency of 2401,9 MHz is used. Callsign  DP1AIS

One transmission cycle consists of 15 sec. FM-voice beacon transmission and 
short 9k6 G3RUH data packets every 15 seconds. Total duration of the above 
described transmission cycle is about 2-3 minutes.

Reports can be sent to DG6BCE@aatis.de


MOZHAETS

There is also a satellite in the Mozhaets series included in this launch but 
no details of its transmissions are known.


LAUNCH DAY BROADCASTS

SATELLITE

The launch will be broadcast via ESA Television on Astra 1 G at 19.2 degrees 
east:

Transponder:                          1.108
Reception frequency:              12551.50 MHz
Polarization:                            Vertical
Symbolrate:                             22Msymb/s
FEC:                                        5/6
TS_ID:                                     1108
ON_ID:                                    1
Service Name:                        ESA
Service provider:                     ASTRA
Service_ID:                             12140
TXT:                                        none

This is always on and will transmit an ESA logo starting three days before 
the launch.
The programme is expected to run for approximately 30mins and will include
the launch sequence live from the Plesetsk launch site.
To set up a new installation for use to receive the Astra 1G signals would 
need this sort of equipment:

A small dish (~50cm) with the correct LNB - (in the UK a "Sky dish and LNB" 
would be fine) -  with either a FTA (free to air) set-top decoder feeding a 
normal TV or a DVB satellite box plugged into the back of a computer (either 
via a USB port or on a PCI card)

Also required is a clear view from the dish to the satellite and, of course, 
some coax cable to connect the two!


INTERNET

The ESA launch programme on ASTRA 1G will also be available as a webstream 
on the Internet.  Details have recently changed and will be updated as soon 
as possible. 
----
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