Mir Amateur Radio Status: Feb 20, 1999
by Miles Mann WF1F
MAREX-MG (Manned Amateur Radio Experiment, North American Division)
Current Schedule for Packet PMS and SSTV:
Last weekend the crew turned on the SSTV for three days, Sat, Sun and Monday. The crew did not have much time for posing in front of the cameras. The camera was just aimed out the Priroda window at the Spectkter module. The images were a little out of focus.
The crew will be keeping both projects on 145.985 FM Simplex for the next few months. We do not have access to the 70cm antenna at this time and we do not have enough Power supplies to run both projects simultaneously. Only one project will be active at a time, either the Packet PMS or the SSTV. The crew will, as time permits, turn on one system then after a period of time, switch over to the other system. These changes are only made during the crews free time. It is not possible to develop an exact schedule announcing the times for each project. The people wanting to use Packet and SSTV will just need to be a little understanding and patient. And I know the world appreciates all of the hard work they have invested.
SSTV Receiving Software:
There are several SSTV software and hardware decoders on the market. Some you can buy while others are shareware. If you are just starting, you may want to try a software version first. I am currently using Pasokon TV Lite for my DOS computer and W95SSTV with my Win95 system. Both systems are easy to use and produce good results.
Mir School Schedules:
MAREX-MG is still running School schedules with the Russian Space Station Mir. The next batch of school schedules have been submitted to Energia for
their review. Occasionally when the Mir crews have free time, Energia allows us to set up these pre-arranged school schedules. Over the next 4 months we expect to run school schedules in the USA, Canada and Australia. MAREX-MG currently has a back log of schools waiting for Mir schedules. We are not currently looking for any more schools in the USA at this time. Note: During school schedules days, the SSTV system will usually be active. This allows the Mir crew to see the children they are talking with.
Mir Crew Members:
The current crew consists of:
SOYUZ TM-28 arrived at Mir on August 16. Mir Soyuz TM-28 crew consisted of Sergei Avdeyev, Gennadiy Padalko. The new crew will be arriving the week of February 20-25 , the are: Viktor AFANASYEV, with French astronaut Jean-Pierre Heignere and Slovak Ivan Bella.
When the 10 day crew change is over, Gennadiy Paldalko and Ivan Bella be returning to earth. The French cosmonaut Jean-Pierre Heignere and Viktor Afanasyev will stay on Mir with Sergei Avdeyev. This will make the Mir crew 27 a three man crew. Sergei Avdeyev will stay on board Mir for an extra three months, bringing his mission time up to approximately 9 months in space continuously. Jean-Pierre mission will last approximately 3 months. Energia informed me that the French Cosmonaut Jean-Pierre did receive training on the MAREX-MG SSTV project, and is planning on using it during this Mission.
Web Page information:
The new MAREX-MG SSTV web is under construction but is now ON line check it out.
PMS Unproto Tips:
Mir and Packet UnProto mode
The Mir PMS (Personal Mail System) also supports the Digital repeating mode called UnProto. I am not going to get into too much detail about UnProto,
for more information check Amateur radio hand books and back issues of Amateur Radio magazine. Basically UnProto is a way of sending packet messages without requiring an acknowledgment from the other station. This mode is similar to RTTY in that, you can have several stations in one big QSO at the same time. Set your UnProto command in your TNC, on my KAM the syntax is "U CQ V R0MIR". Then switch to Converse mode (enter K at cmd: prompt). Now everything you type will be transmitted in UnProto Mode. If the Mir station hears your transmission, the Mir PMS Digi will rebroadcast your information with a range of over a 1000 miles. Below is a short UnProto between a station in Massachusetts and Alabama, using the Mir Digi. 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 you message will ever be heard, but if the Mir Digi does rebroadcast your line of text, then you can be assured that someone saw 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". Before you try Unproto on Mir, I recommend that you practice on a Terrestrial Digi first before attempting to use the Mir station for Digi-repeating. 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. Occasionally the System Operators say turn off Unproto (Digi = OFF) to improve the Mail Box traffic flow. The Mail box access should always have top priority over other traffic. Also there is a good time and a bad 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 Personal Message System (PMS). Any
Index packets going to the R0MIR-1 address.
The only real safe time to use UnProto, is when the Mir PMS is in its 2 minute time-out mode. This time-out is caused when the station connected to the Mir PMS is out of range and cannot log out of Mir. No one can log into PMS Mail box (R0MIR-1) until the connected station times out. Time-outs are the best time to use UnProto. Before using UnProto, monitor Mirs down link to see who is using the PMS Mail box port "R0MIR-1". If you do not seen any Index packets from Mir PMS to the ground station using to the "R0MIR-1" port for 60 seconds, you can assume the connected station is out of range of the Mir PMS and its "UnProto time". 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 Mail box "R0MIR-1", you should end your Unproto QSO and let the Mail box users have access to the PMS.
Previous Testing of Two-way Connects:
In 1993 WA2GSY in New Jersey (now W2KQ) and I WF1F in Boston made arrangements to test the efficiency of FULL-TWO-WAY packet connects verses Unroto messages. Unfortunately I have lost the original logs from the test, but I do clearly remember the results. We made arrangements for the
Mir Amateur Radio station to move to a private channel for a weekend. Then Joe and I attempted a Full-TWO-WAY packet Digi connect via the Mir PMS on a perfectly clear channel. The orbit was a perfect pass, traveling from Texas to Maine. The 10 minute pass had good elevation. Both of our
stations were similarly equipped and running high gain antennas with approximately 1200 watts ERP of transmit power each. At the beginning of the pass, we sent a few Unproto packets, and then Joe issued the full two-way connect to my station. After the initial log-in we each sent each other two simple lines of ASCII text and then logged out. Now you must remember we had a perfectly clear channel. There were NO other stations on frequency because we had moved the PMS to a private channel. There was no interference from any ground stations. It required over 4 minutes for us to exchange the 2 lines of text. The total number of packet transmission from all three transmitters was over 200 packets. Every packet which I sent, had to be heard, acknowledged and retransmitted by the Mir PMS. The same packet was then sent to WA2GSY and had to be heard and acknowledge. The acknowledgment from WA2GSY then had to go back to Mir and Acknowledgement had to be re-broadcast from Mir back to my TNC. Four transmission are required for each original packet. However since my station in Boston cant hear when Joes system in New Jersey was transmitting, there were dozens of packet collisions. These collisions are what causes the efficiency of two-way packet to drop. With a full-two-way connect each packet sent must be acknowledged. This causes a tremendous amount of over head in this particular satellite configuration. The efficiency of full-two-way connects via Mir is less than 10% on a perfectly clear channel. Now if you add in the normal amount of traffic to the Mir public channel, you can see that full-two-way connects are a complete waist of time. The efficiency of Unproto on the other hand is greater than 50%. And Unproto is more band friendly. The existing design of the Kantronics KPC-9612 does not allow us to filter out the difference between Unproto and Two-way connects its just all or nothing. So we need to rely on your courteous corporation and for people to help spread the word on the correct operating procedures.
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 Mail Box.
The best way to track satellites is to get access to a good satellite tracking program. There are numerous programs on the market, both for sale and share ware.
The best place for current satellite position date (Kep) data is at the
CelesTrak web page http://celestrak.com/
Copyright 1998 Miles Mann, All Rights Reserved. This document may be freely distributed via the following means - Email (including listservers), Usenet, and WorldWideWeb. It may not be reproduced for profit including, but not limited to, CD ROMs, books, and/or other commercial outlets without prior written consent from the author. Images received from the MAREX-MG SSTV system on the Russian Space Station Mir are considered public domain and may be freely distributed, without prior permission.
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