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[jamsat-news:645] * SpaceNews 22-Sep-97 *

* SpaceNews 22-Sep-97 *

BID: $SPC0922



SpaceNews originates at KD2BD in Wall Township, New Jersey, USA.  It
is published every week and is made available for non-commercial use.

During the period 19-Aug-97 to 13-Sep-97 excellent signals have once again
been received from ORSCAR-11's 145.826 MHz beacon.  Telemetry reports that
conditions are normal on the spacecraft.  The battery voltage has been
maintained in the range 13.9 to 14.4 volts.  The internal temperatures
are slowly increasing from the minimum values observed at the end of June
(battery -0.4C, telemetry electronics -1.6 C).  The battery temperature
is now 8.4C, and telemetry electronics is 6.8C.  The increased temperature
is due to a reduction in solar eclipse times, which is expected to continue
into October.

The WOD survey of channels 10, 20, 30, 40 (+Y, -X, +X array currents, array
voltage) dated 25 June was transmitted until the end of August. The timing
of this WOD coincided with the maximum eclipse times.  This WOD is now
available from my web site (details below).  At the end of August a further
survey of the same channels was taken, dated 26-Aug-97.  This was quickly
followed by channels 21, 31, 41, 51 (equipment currents) dated 30-Aug-97,
and then by channels 10, 20, 30, 40, dated 03-Sep-97, which are now being

A single AMSAT-UK bulletin dated 21-Jun-97, by Richard, G3RWL, has been
transmitted.  This featured Sputnik-1 40th anniversary, MIR frequencies,
and RS-10 news, and the Keplerian elements for OSCAR-11.

Considerable interest is now being shown in the Mode-S beacon, as operators
prepare for Phase-3D.  Reports indicate that it is a very weak signal, and
therefore ideal for testing converters, once they have been set up using the
much stronger signal from DOVE.  Reports have indicated that the signal from
OSCAR-11 is around 24 dB below that of DOVE.  There are however considerable
variations in the comparisons which vary between -15 dB and -36 dB!  Before
the beacon partially failed the signal was measured at -3 dB below DOVE.

Hans, HB9AQZ, reports hearing the beacon using a 26 turn helix, mounted
in the shack, and pointing through a double glass window.  Ib, OZ1MY, in
Copenhagen heard the beacon with two 16 turn helixes, feeding an SSB
Electronics downconverter and pre-amp (combined noise figure 1.5 dB).
Trevor, VK4AFL, reports S3 signals with a 60 cm dish, two turn helix feed,
Down East Microwave converter and pre-amp.  Victor, OE1VKW, reports S 3-4
signals using a 67 element antenna, horizontal polarization, and UEK-2000
SAT.  On the same equipment DOVE was received at S 7-8.  Thanks for all
the reports.

The operating schedule is unchanged.

	ASCII status (210 seconds)
	ASCII bulletin (60 seconds)
	BINARY SEU (30 seconds)
	ASCII TLM (90 seconds)
	ASCII WOD (120 seconds)
	ASCII bulletin (60 seconds)
	BINARY ENG (30 seconds)

There are also additional status blocks after each bulletin is transmitted,
and between ASCII TLM and WOD.

The Mode-S beacon is ON, transmitting an unmodulated carrier, but telemetry
indicates that it has partially failed, and delivering half power.  Any
reports of reception on 2401 MHz would be most welcome, and should be
directed to Clive Wallis at: g3cwv@amsat.org.

The 435.025 MHz beacon is normally OFF.  However, it can sometimes be heard
when the satellite is being commanded by ground control, (ie. 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.

OSCAR-11 users are welcome to visit Clive Wallis' OSCAR-11 Web site.  It
contains some software for capturing data, and decoding ASCII telemetry and
WOD.  There is an archive of raw data (mainly WOD) for analysis, which is
continually being expanded, as new data is captured.  The URL is:


[Info via Clive Wallis, G3CWV]

Manfred, XQ2FOD, has released version 2.3 of his popular Fodtrack satellite
tracking program.  Manfred uploaded Fodtrack to the KO-23 satellite where
is appears as file #27D97.

FodTrack is a free tracking package that does the antenna steering and
radio tuning for a satellite groundstation.  It has features for both
fully automatic digital satellite stations and for semi-manual operation
on analog transponders.  It interfaces to several radios, and to a G5400/5600
or similiar rotator.  Schematics for all interfaces are included, and the PCB
layout for the rotator interface is included also (the other interfaces are
too simple to justify a PCB).

Fodtrack is DOS-based, and runs well under DESQview.  It can also be run
under Windows, but it is NOT Windows-specific.

Version 2.3 includes the following new features:

- Doppler tuning for converter operation on all sat bands from 2 meters to 
  24 GHz!

- Possibility of having several frequency setups for each satellite (useful 
  for mode J versus mode S, different uplink frequencies, etc).

- The GPS routine now supports three types of NMEA datgrams: GLL, GGA and RMC.
  (Manfred hopes that FodTrack is now compatible with all GPS receivers.)

- The program is no longer case-sensitive!

- Good news for FT-736 users: Band change can now be handled automatically!

- A few bugs were fixed, and probably some others were introduced, but it's
  better not say this!

If you have FODTRK in your select equation, the file will download 
automatically when you access KO-23.  Otherwise, you can of course request
it manually.

[Info via Manfred, XQ2FOD]

* RS-12 NEWS *
Rusty, NM1K, reports hearing TF3FKT and OY4TN on RS-12 with strong signals.

The following is from Michael Foale on-board the space station Mir:

 Stat   : PR   
 Posted : 09/16/97 10:27
 To     : ALL    
 From   : R0MIR  
 @ BBS  :        
 BID    : 
 Subject: Mir Status

 Since the EVA with Anatoli and me, we have been getting the station back 
 into a condition to receive the shuttle, and its payload, for which we 
 will have to find space.  Priroda has intermittent power, and most likely 
 tomorrow will be turned on permanently.  Safex will not be turned on 
 until we are given permission by TSUP in Moscow.  Priroda will be sharing 
 the energy from the two Spektr solar arrays, with Krictal, and first 
 priority will be given to complete US and French science experiments that 
 require power in Priroda, starting tomorrow.  I have completed the second 
 harvest of Greenhouse, of Brasica Rapa, and will be planting both 
 original earth seeds, and space produced seeds, today, in a new root 
 module.  I will harvest all these plants during the docked phase of STS 
 86, in late September.

 We have had in the course of a week or so, two GNC control problems with 
 the guidance computer. It consists of 3 identical blocks, which vote.  
 Last week, the computer failed and was switched out in 24 hours with an 
 older unit, still on board.  On sunday, the older unit also failed, and 
 yesterday a block from the earlier failed unit was placed into the 
 currently installed computer.  Today we again have attitude control, 
 solar pointing, and a margin of power.  

 Mike. R0MIR.

[Info via N6CO and WF1F]

The Mir PMS (Personal Mail System) supports a digital repeating mode called
UNPROTO.  Without getting into too much detail, UNPROTO is a way of sending
packet data frames without requiring an acknowledgment from the receiving
station.  This mode is similar to RTTY in that it is possible to have several
stations in one big QSO at the same time.  Set the UNPROTO command in your
TNC using the command: "U CQ V R0MIR".  Switch to converse mode, and
everything typed on the packet terminal will be transmitted in UNPROTO mode.
If the Mir station hears your transmission, the Mir PMS Digi will rebroadcast
your packet within a range of over a 1000 miles.   Below is a short UNPROTO
contact between a station in Massachusetts and Alabama, using the Mir
Digipeater.  The stations were arranging to meet on OSCAR 13 when the
Mir pass was over.

WF1F>CQ,R0MIR*/V [04/21/93  22:22:09]: <UI>:
hi Tim can you work OSCAR 13?

N8DEU>CQ,R0MIR*/V [04/21/93  22:22:30]: <<UI>>:
Hi miles, yes what freq?

WF1F>CQ,R0MIR*/V [04/21/93  22:22:40]: <UI>:

The UNPROTO mode does not guarantee your packet frames will be successfully
copied by any other ground station, but if the Mir digipeater does re-transmit
your line of text, then you can be assured that someone will see it.  The
line of text you send will be repeated with an asterisk after it, "R0MIR*".
If you do not see the asterisk, then Mir did not hear your packet.  UNPROTO
does have its drawbacks, but it is much more efficient to use on Mir than
the direct two-way connect method.  Full two-way packet connects via the Mir
PMS are not recommended because they use up too much resources and excessive
retires.  You can pass 20 times more data using UNPROTO than the full-two-way
connect method.  Before you try UNPROTO on Mir, it is recommended that you
practice using a terrestrial digipeater first before attempting to use the
Mir station for Digipeating.  (Editor's note: Many terrestrial packet nodes
do not pass UNPROTO frames since they frequently add to channel congestion,
and do not take good advantage of the node's capabilities.)  If you make a
few UNPROTO calls and do not get any echo's back from Mir, it is probably
because UNPROTO is turned off or because of a collision between packet frames.
Everytime the Mir's Paccom HandiPac TNC is reset, UNPROTO defaults to OFF.
Also, there is a right time and a wrong time to use the UNPROTO mode with
Mir PMS.

Do NOT use UNPROTO when:

1. The Mir crew is operating in voice mode.

2. When the Mir PMS is connected to another station that is actively
   sending/receiving information from the mailbox.

The only real safe time to use UNPROTO is when the Mir PMS is in its 5 minute
time-out mode when the station connected to the Mir PMS is out of range and
cannot log out of Mir.  No one can log into PMS mailbox until the connected
station times out.  Time-outs are the best time to use UNPROTO.  Before using
UNPROTO, monitor Mir's downlink to see who is using the PMS mailbox port
R0MIR-1.  If you do not seen any information <I> packets being transmitted
from the Mir PMS to any ground station using the R0MIR-1 port for 90 seconds,
you can assume the connected station is out of range of the Mir PMS and its

The shorter the UNPROTO sentence, the greater your success of a PMS repeat.
Long sentences may get clobbered by other stations.  If you are in the middle
of an UNPROTO QSO and you see someone connect to the PMS mailbox R0MIR-1,
you should end your UNPROTO QSO, and let the mailbox user have access to
the PMS.

Good luck and lets be courteous to everyone.

Remember, only 1 station can connect to Mir's PMS at a time, and try avoid
using UNPROTO when someone is actively using the PMS.

[Info via Miles Mann, WF1F]

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/
INTERNET  : kd2bd@amsat.org, magliaco@email.njin.net

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