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Re: PMS usage suggestions?



Bob,

That is a good question!
Considering optimum conditions, and no QRM it would take about 2 minutes. 
This includes the connection time, listing, and reading, then disconnecting. 
That would exceed a 1 minute rule.
This is assuming the ground station was set up tracking, correcting for 
doppler etc. In "most" cases there are a lot of rejection frames too!
Easier said than done...
If there is QRM (which there almost always is) that task may not even be 
compleated.

I am trying to be good, and only running 5 watts here with an omni vertical 
and horizontal beam. I get swamped by the "big guns".
I would not even attempt working the PMS with my current operating 
conditions!

73, Scott



>From: Bob Bruninga <bruninga@usna.edu>
>To: Scott Avery <wa6lie@msn.com>
>CC: sarex@AMSAT.Org, <amsat-bb@AMSAT.Org>
>Subject: Re: [sarex] PMS usage suggestions?
>Date: Sun, 3 Mar 2002 10:12:48 -0500 (EST)
>
>So how quickly could you get on, get a list of the last 10 messages and
>read a 3 line message in the absence of QRM?
>
>Bob
>
>On Sat, 2 Mar 2002, Scott Avery wrote:
>
> > Hello Bob and all....
> >
> > Nice idea, but how do you get everyone to understand or conform?
> > It is a hard task.
> > It seems I have been here before on MIR with it's PMS.
> > We have a lot on HAMS that never got to experience MIR operations.
> > So, here is what I sent around back when MIR was up.
> > ISS/RS0ISS packet operations are basically the same as what MIR was.
> > There are differences in the TNC used, and some of the commands, but the
> > basic principle are the same.
> >
> > Attached below is a user's guide I typed a long time ago, and was widely
> > used on MIR, and helped in educating the users.
> > Miles, WF1F also has something more updated on ISS operations.
> >
> > Please read, and try to understand, This is NOT an operations manual for
> > ISS. Other than that... Basically the same animal....
> >
> > 73, Scott
> > CU on ISS....
> >
> >
> >
> >
> >                              HOW TO WORK R0MIR-1
> >
> > The MIR Space Station is currently orbiting the earth about every
> > 95 minutes while traveling at roughly 17,000 MPH. Due to the fact
> > that MIR is a moving object, and radio frequencies being involved
> > here, Doppler corrections may be needed. On the 2 meter band, the
> > Doppler is a maximum of 3.5 khz on a pass directly overhead (90 
>degrees).
> > On a pass say 10 degrees above the horizon, the Doppler is small
> > about 1 khz. This can be a very important factor in working the packet
> > Personal Mail System. This is because packets may become distorted.
> > Here are some items to look at in your station for successful attempts.
> >
> > 1. LOCATION
> >
> > If you are in a bad location where it might be difficult to get
> > a signal out, you might be limited to the number of passes that
> > you can work. You might want to look into a simple 1/4 wave 2 meter
> > groundplane. This antenna has a good lobe looking up. (pre-amp 
>suggested)
> > If you are in the clear to your horizons, you have it made.
> > However, Doppler and antenna type will be your disadvantage.
> > For the average HAM station running say a 50 watt radio, and a J pole
> > antenna has a great advantage on MIR passes that are up to about
> > 20 degrees above the horizon! Doppler isn't a real consideration
> > and your antenna pattern is ideal for something up to 20 degrees
> > above the horizon, or a bit more! Most radios will work, and no
> > frequency corrections are needed. Doppler up on UHF is around 10 KHZ
> > and Doppler compensation is needed! A MUST for SAFEX or any UHF
> > satellite operations.
> > Note: SAFEX not operational at this writing.
> >
> >
> > 2. TRACKING
> >
> > You will need some satellite tracking software to know when and where
> > MIR will be in your area. There is a lot of tracking software available
> > on the internet. I use STSPLUS, and have for over 15 years. Keplerian
> > information on MIR and other satellites is updated twice weekly, and can
> > be found on your local BBS or on at Amsat.org
> >
> > 3. FREQUENCY
> >
> > The frequency For ISS is 145.800rx PLUS 145.99tx (YOU) World Wide. (1200
> > baud packet)
> >
> >
> > 4. PACKET WISE
> >
> > If you are not familiar with packet connections or mailboxes, do some
> > experimentation on the ground first before trying to operate MIR.
> > The TNC on MIR is a Kantronics KPC-9612+ V 8.1 and is operating at
> > 1200 baud ONLY. Here is the HELP that you would get on R0MIR-1 when
> > using the Help (H) command.
> >
> > Note: ISS uses a Pacomm TNC, and the command list is a bit different!
> >
> >
> > B(ye)         PBBS WILL DISCONNECT
> > E(dit) n [BPTYNFH] [>tocall] [<fromcall] [@BBS] "old" "new"
> > J(heard)      CALLSIGNS WITH DAYSTAMP
> > J S(hort)     HEARD CALLSIGNS ONLY
> > J L(ong)      CALLSIGNS WITH DAYSTAMP AND VIAS
> > L [x [y]] [;] LIST MESSAGES x THRU y YOU CAN READ
> > L <|> call    LIST MESSAGES FROM OR TO CALL
> > LB            LIST BULLETINS
> > LC [cat]      LIST CATEGORIES
> > LL n          LIST LAST n MESSAGES
> > LM(ine)       LIST UNREAD MESSAGES ADDRESSED TO YOU
> > LO [+|-]      LISTING ORDER
> > LT            LIST TRAFFIC
> > LTn           DISPLAY LOCATION TEXT n=1-4
> > K(ill) n      DELETE MESSAGE NUMBER n
> > KM(ine)       DELETE ALL READ MESSAGES ADDRESSED TO YOU
> > R(ead) n      DISPLAY MESSAGE NUMBER n
> > RH n          DISPLAY MESSAGE n WITH HEADERS
> > RM(ine)       READ ALL MESSAGES ADDRESSED TO YOU
> > S(end) call   SEND MESSAGE TO callsign
> > S[B|P|T] call SEND BULLETIN, PRIVATE, or TRAFFIC
> >
> > Please don't use the Help command on MIR. This is STANDARD to MOST
> > TNC's and doing so just limits the use of MIR by other stations.
> > There can only be ONE user connected to R0MIR-1 at a time.
> >
> > 5. BE PREPARED
> >
> > If you wish to send a message to the crew, have a file of message READY
> > to go! What I usually do is make a message to R0MIR BEFORE I even send 
>it.
> > On my KPC-9612, I get in my mailbox, and SP R0MIR@MIR Then enter the
> > subject and then the message. When MIR is in range, and the mailbox is
> > not being used, I forward the message. My TNC talks to MIR's TNC and
> > goes through the forwarding process. This is ALOT quicker! I send 3.7K
> > of info in one minute! This includes the connect to disconnect time.
> > Consult YOUR TNC users manual for forwarding mail to a station.
> >
> > Don't try to send a message to your buddy down the street to MIR's
> > PERSONAL Mailbox. It will NOT allow 3rd party messages. If you try,
> > you will get a response - MESSAGES MUST BE ADDRESSED TO THIS STATION.
> >
> > 6. BE COURTEOUS
> >
> > Please don't try connecting to R0MIR-1 when someone else is already
> > connected. You will get a R0MIR-1 **BUSY. When you get this, don't
> > keep trying while others are connected. This just messes up the other
> > station, and it is interference and will just take that much LONGER
> > for the user to finish before he/she disconnects. Would you like
> > others interfering with your connects to MIR? Look for the D frame
> > from R0MIR-1 to the connected station. Using MCOM ON will allow you
> > to see all these packets. Here is what MY KPC-9612 would show.
> >
> > R0MIR-1>WA6LIE/1 [05/13/98 22:18:04]: <<D>>:
> >
> > After you see this, hopefully, the ground station has sent his/her
> > disconnect to R0MIR-1, and it will be ready for the next connect.
> > -----------------
> >
> > R0MIR
> > This is the callsign of MIR. This port has no value to working MIR
> > except credit towards a QSL card. There is nobody at the keyboard.
> > -----------------
> >
> > QSL REQUESTS USA and WW except Europe:
> >
> > Dr. Dave Larsen - N6CO/K6MIR
> > POB 1501
> > Pine Grove, California
> > 95665
> > USA
> >
> > Please include a SASE (Business Size Envelope) and one IRC > for
> > international. If you are sending an IRC, Please make sure it is dated
> > 1998, as the post office won't accept IRC's dated over 1 year old.
> > "Green Stamps" are appreciated for covering additional costs.
> > ------------------------------------
> >
> > If you have any questions, drop me a note!
> >
> > 73, Scott
> >
> > E-Mail: wa6lie@msn.com
> > Packet: wa6lie@wa6lie.#wcca.ca.usa.noam
> >
> >
> >
> >
> > >From: Bob Bruninga <bruninga@usna.edu>
> > >To: sarex@AMSAT.Org, <amsat-bb@AMSAT.Org>
> > >Subject: [sarex] PMS usage suggestions?
> > >Date: Sat, 2 Mar 2002 10:19:34 -0500 (EST)
> > >
> > >There will of course be no universal agreement of the best way to use 
>the
> > >PMS on orbit, but we do need to look at some strategies that might help
> > >in defining expectations for maximum utility of the asset.
> > >
> > >Here is just one such possibility to consider over populated 
>continents:
> > >
> > >(*) A user is limited to one minute.
> > >
> > >    This means, the clock starts when you send your first connect 
>request,
> > >    and  the buzzer goes off when 1 minute is up.  At that point, you 
>must
> > >    issue a disconnect.
> > >
> > >The logic behind this recommendation is as follows.
> > >
> > >1) It would allow as  many as say a dozen or more successful users per
> > >    pass over the USA and or europe (if they do it right)
> > >2) It would encourage users to know in advance how to work it
> > >3) It would encourage people to prepare their uplinks OFF LINE.
> > >4) It would encourage people to get the message list by monitoring 
>someone
> > >    elses downlink rather than wasting their precious minute with a
> > >    duplicate download of the same user list.
> > >5) Awards could be given for the shortest access times. (You can get a
> > >    list in under 15 seconds Connect-to-disconect)
> > >6) It would encourage stations to use the proper station for SUCCESS.
> > >    (constant retries means your station is not up to the task)
> > >7) Each person's access is an EQUAL measureable quantity.  We no longer
> > >    have to make subjective judgements about "other peoples" use of the
> > >    system.
> > >8) The order of magnitude higher "success" rate would reward everyone
> > >    monitoring with being able to capture the essence of the PMS 
>traffic
> > >    without even connecting.
> > >9) We would have a working PMS that shows the world what Amateur radio 
>can
> > >    do.
> > >
> > >The status-quo alternative of having it turned off, and or quibbling
> > >forever about who should and who should not be using it doesnt do 
>anyone
> > >any good...
> > >
> > >just an idea...
> > >
> > >de WB4APR, Bob
> > >
> > >----
> > >Via the sarex mailing list at AMSAT.ORG courtesy of AMSAT-NA.
> > >To unsubscribe, send "unsubscribe sarex" to Majordomo@amsat.org
> >
> >
> >
> >
> > _________________________________________________________________
> > Get your FREE download of MSN Explorer at 
>http://explorer.msn.com/intl.asp.
> >
>
>de WB4APR@amsat.org, Bob
>
>PCsat WEB  page     http://www.ew.usna.edu/~bruninga/pcsat.html
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>




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