From: dave@ips.oz.au (Dave Horsfall)
Newsgroups: aus.radio.amsat
Subject: NEW MICROSAT EXPECTED THIS YEAR!
Date: 7 Sep 92 00:04:05 GMT
Distribution: aus
Organization: IPS Radio and Space Services.  Sydney, Australia.

HR AMSAT NEWS SERVICE BULLETIN 242.03 FROM AMSAT HQ
SILVER SPRING, MD AUGUST 29, 1992     BID: $ANS-242.03
TO ALL RADIO AMATEURS BT

EXPECT ANOTHER OSCAR MICROSAT IN 1992!!!

Tom Clark (W3IWI) is relaying information from David Liberman(XE1TU).
David is project manager for UNAMSAT-1 -- the first Mexican amateur
satellite being built at UNAM, the Autonomous University of Mexico.

UNAMSAT-1 is another of the MICROSAT series and has much in common with
AO-16/DO-17/WO-18/LO-19.  As with the earlier MICROSATs it will have five
modules, each about 20 cm on a side.  Four of the five modules are updated
clones of existing MICROSAT hardware/software:

 -- Dual 70cm PSK transmitters (designed by YT3MV)
 -- V40 CPU (designed by WA7GXD and others from TAPR, with
     modifications by I2KBD and ITAMSAT)
 -- Power system with BCR (by KE3Z/ARRL) and batteries
 -- 5-channel 2M FSK receiver (by W3IWI)
 -- Similar software to other MICROSATs (by NK6K and G0/K8KA)
 -- AART Bus architecture (by W3IWI and N5BRG)

 The main differences from the earlier MICROSAT configuration are:

 -- the V40 CPU will have 4 MB of bulk RAM vs 8 MB.
 -- UNAMSAT-1 will be equipped with Gallium Arsenide solar panels (vs.
     the BSFR technology flown on the MICROSATs).

The innovative new addition in UNAMSAT-1 is the brand new on-board
experiment in the 5th "TSFR" ("This Space For Rent") module:

UNAMSAT-1 primary mission is to act as meteor sounder.  It will contain a
40.097 MHz transmitter with 60 watts output during pulses from which can be
varied from 1 to 10 msec in duration and with a pulse repetition rate of 1
to 10 seconds, as controlled by a 68HC05 CPU.  The meteor echoes will be
detected on a receiver at the same frequency designed to detect the
returned echo and measure its doppler shift.  The use of the meteor
sounder is to obtain research data on the full-sky spatial and velocity
distribution of meteors, with the focus on a search for high-velocity
meteors originating outside our solar system.

The 41 MHz frequency for this transmitter is in accordance with the
ITU frequency allocations table for scientific research and both the 41
MHz and amateur frequencies have been licensed by Mexican authorities.
The transmitter is frequency controlled and has a class "E" power amplifier.

The meteor receiver is a SSB "zero-IF" design (suggested by W3IWI) and
the return echoes are digitized and stored in the normal V40 MICROSAT
computer's RAM.  After each pulse, the spectrum of the received signal
will be determined using the onboard V40 as a DSP Fourier Transform
spectrum analyzer.  If a meteor echo is detected, the echo will be saved
for later transmission as a special telemetry frame.

The 1-10 second repetition rate for the meteor transmitter will be
adjusted depending on the state of charge of the batteries and other
spacecraft power requirements, and also on the time domain requirements of
the echoes.

Detailed telemetry formats for meteor "radar" are still being defined.
Data will be sent using standard amateur AX.25 packet specifications.

When UNAMSAT-1 is not involved in meteor research, it can be turned into
a standard PACSAT message store-and-forward satellite.

Also, still to be finalized are the detailed 2M uplink and 70cm downlink
amateur frequencies.

XE1TU has been responsible for technical development of UNAMSAT-1 along
with the team of hams and students at the University.  The hams are
XE1MGI, XE1XUS, XE1YLS in Mexico City.  Scientific direction for the
project has been provided by UNAM Professor of Astronomy Arcadio Poveda.
AMSAT-NA provided technical details of its MICROSAT satellites to UNAM.
During the development  of UNAMSAT-1, technical assistance from AMSAT-NA
has been provided by W3GEY, N4HY, NK6K, W3IWI and WD4FAB.  ITAMSAT
assistance was coordinated through I2KBD.

The UNAMSAT-1 launch will also be the beginning of a new era.  Along with
a larger meterological satellite, it will be launched by the Russian Space
Agency and by the Russian Academy of Sciences on a decommissioned SS-18
ICBM into an orbit about 1000 km high.  At this time the launch is
scheduled for the first week of December, 1992.  Details for the launch
are being worked out at the present and we will give you the details as
soon as the become available.

[The AMSAT News Service (ANS) would like to thank W3IWI and XE1TU for this
 this bulletin item.]

-- 
Dave Horsfall (VK2KFU)         VK2KFU @ VK2RWI.NSW.AUS.OC
dave@ips.OZ.AU                  ...munnari!ips.OZ.AU!dave