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Mir Radio Status January 13, 2000

Mir Amateur Radio Status: January 13, 2000

By Miles Mann WF1F, 
MAREX-NA (Manned Amateur Radio Experiment, North American Division) 

Mir Status:
The Russian Space Station Mir is currently un-manned and is flying on
remote control.
   All of the Amateur Radio experiments are currently disconnected.  The
tentative plan,
  is to send a new crew to the Mir Space Station in March 2000.  When the
new crew moves
  into Mir, the Packet and SSTV station will be re-activated on 145.985
FM Simplex

The MAREX-NA Group is currently working on our next generation of Slow
Scan TV for the 
International Space station.  Work on the SSTV project is well under
way.  The MAREX-NA
  team is actively testing the MAREX-NA SpaceCam1 SSTV software on H.F.
and VHF. We want 
to make sure the SpaceCam1 software is compatible with all existing SSTV
software systems.
   If you have access to H.F.,  you may try listening for SSTV activity
20 meters around
  14.230 and 14.235.  The MAREX team is frequently testing new versions
of software in
  this part of the band.

The new SpaceCam1 SSTV system will be a PC (laptop)
software based system, with more features than the previous Mir SSTV

The original MAREX-NA Mir SSTV system was designed to be very simple for
the Mir crew to
use. However the simplicity of the original system came with a few
After 9 months of use on board the Russian Space Station and over 20,000
transmitted, the Mir crews came up with several suggestions for the next
  of SSTV for the International Space Station.

Mir Crew Suggestions:
1.They wanted to be able to automatically save images received from
Earth on
a PC disk for viewing at a later date.
2.The ability to transfer images from a Digital Still Image camera into
SSTV system (SLIDE SHOW mode Live Camera or pre save Disk images).
3.The ability to automatically repeat the same image many times (BEACON

The new MAREX-NA SSTV SPACECAM1 system for ISS will have all of
these features and more.
The hardware configuration of the SSTV system will consist of a VHF/UHF 
transceiver, a Russian Lap-Top PC and an Audio isolation switch box.  
The new SpaceCam1 proposal will support both USB cameras and composite
RS-170 video
  input connections. The specific cameras for the project have not been
chosen at this time.

Other proposed features:
Repeater Mode
In the Repeater mode, Earth stations will be able to use the SpaceCam1
as a SSTV repeater.
You will be able to send SSTV images to SpaceCam1 and then a few seconds
SpaceCam1 will re-broadcast the same image back to Earth.  The repeated
will also be saved to a JPG file on the SpaceCam1 PC.

Digital Camera:
The ISS crew will have Digital Still image cameras.  These cameras can
store the 
images in a format which can be read by the SpaceCam1 program.  The ISS
crew will 
have the option of coping the images into the SpaceCam1 computer.  This
will allow 
the people on Earth to see the crews latest pictures they have taken in
other parts of the space station.

Kenwood Modifications:
The Space Station Mir is using two different models of Kenwood radios
for the amateur 
radio experiments.  The Kenwood TM-733 is connected to the Kantroinics
KPC-9612 TNC 
for the packet radio experiment.  The TM-V7 is connected to the Tasco
SSTV system.  
Both radio are dual band 2-meter / 440 transceivers.  In space we have a
problem with Intermod and De-sensing of the Amateur radio equipment. 
This interference 
comes from both the Earth and from the commercial transmitters on Mir. 
(Note: there 
have never been any reported cases of the Mir Amateur Radio equipment
causing any 
interference with any of  the commercial equipment on Mir)
To solve the de-sensing problem on 2-meters the MAREX-NA team delivered
a custom 
built DCI 2-meter  passband/notch filter, which is installed on the Mir
packet system.  
The filter sucesfuly 
cured all of the interference problems, however we could only run
2-meters while the filter was 
installed.  The next step was to experiment with the TM-733 to see if it
could be converted
from a single coax cable to separate coax cables for each band (2-meters
and 440).
I was able to covert our lab TM-733 to support the new modifications and
I tested the
configurations in the Boston Intermod Alleys (Rt. 128 Waltham and Rt.
495 Nashoba Ski hill).
With separate coax cables per band, it is easy to install external band
pass filters to suit
your specific needs.  The complexity of the modification may be too much
for the crew to handle
in space, so at the present time the radios on Mir will remain
However, here are the steps, if you would like to modify your radio.
The procedure is not guaranteed and it will void your warranty.

Note:  Early production models of the TM-733 came with split coax
cables, the majority
of radios in USA are running a single coax pig-tail for 2m/440.

Remove the top and bottom covers of the TM-733.
The top board is the 2-meter board, the bottom board is the 440 board.
The existing coax is connected to the 440  board.
There is a pin connecting the two antenna connections together.  The pin
runs from  the 2-meter antenna pads into the 440 board antenna pads. 
Locate the pin and 
use Solder wick and remove the solder from the pin where it attaches to
both boards.
If you remove all of the solder the pin should pull out easily.
After the pin is removed, install a pig-tail coax cable for the 2-meter
There is a pre-drilled hole in the back heat-sink for the coax cable.
Notice how the cable is installed for the 440 side, and install the
2-meter cable
in a similar fashion.  The center lead of the coax will be attached to
the pad where
the pin was removed.  The coax shield will be installed on the pad
closest to where the 
cover mounting screws is attached.
Now just reassemble and test.  
Good luck.

Mir QSL Update:

Note:  We are currently out of QSL cards for the Mir Amateur Radio
The MAREX-NA team has designed a new Mir QSL card which is currently in
hands of the printer.  The card proofs have been sent to
Energia/MAREX-RU for 
final approval.  We hope to send the final card to the printers in
January 2000.    
I  would like to thank you all for being patient on getting your QSL
We hope to begin shipping the new cards in Q1 2000.

Copyright 1999 Miles Mann, All Rights Reserved.  This document may be
distributed via the following means - Email (including listservers),
and World-Wide-Web.  It may not be reproduced for profit including, but
limited to, CD ROMs, books, and/or other commercial outlets without
written consent from the author.
Images received from the MAREX-NA SSTV system on the Russian Space
Mir are considered public domain and may be freely distributed, without 
prior permission.


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