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- Date: Sun, 7 Aug 94 04:30:27 PDT
- From: Ham-Space Mailing List and Newsgroup <ham-space@ucsd.edu>
- Errors-To: Ham-Space-Errors@UCSD.Edu
- Reply-To: Ham-Space@UCSD.Edu
- Precedence: Bulk
- Subject: Ham-Space Digest V94 #217
- To: Ham-Space
-
-
- Ham-Space Digest Sun, 7 Aug 94 Volume 94 : Issue 217
-
- Today's Topics:
- GPS base stations in Scranton PA area? (2 msgs)
- GPS Freq and antenna questions
- HELP NOAA Series
- Low-band Satellite transponders?
- MacSPOC
- MacSPOC updates (2 msgs)
- STS-65 Commemorative TLI Burn
- What SAT's can I hear on a Scanner ?
-
- Send Replies or notes for publication to: <Ham-Space@UCSD.Edu>
- Send subscription requests to: <Ham-Space-REQUEST@UCSD.Edu>
- Problems you can't solve otherwise to brian@ucsd.edu.
-
- Archives of past issues of the Ham-Space Digest are available
- (by FTP only) from UCSD.Edu in directory "mailarchives/ham-space".
-
- We trust that readers are intelligent enough to realize that all text
- herein consists of personal comments and does not represent the official
- policies or positions of any party. Your mileage may vary. So there.
- ----------------------------------------------------------------------
-
- Date: 5 Aug 1994 23:52:41 -0400
- From: panix!not-for-mail@uunet.uu.net
- Subject: GPS base stations in Scranton PA area?
- To: ham-space@ucsd.edu
-
- In <oiEbZxa00WB6BAu24y@andrew.cmu.edu> Ergin Guney <eg23+@andrew.cmu.edu> writes:
-
- >Excerpts from netnews.rec.radio.amateur.space: 4-Aug-94 GPS base
- >stations in Scrant.. by George Brown@partech.com
- >> Is anyone aware of any GPS base stations in the Scranton PA area? We have
- >> some survey work and are contemplating using a GPS receiver (need
- >> differential for better accuracy) to support the effort. We would like to
- >> know if there is a base station near, accuracy, cost of access, etc. Or
- >> is there another alternative that would give 1-2m accuracy in real-time?
- >> Any help would be appreciated.
-
- >Either you have been misinformed, or I am missing something big. I
- >pretty well know that GPS signals aren't transmitted by any "base
- >stations" on land. They come from 12 or so satellites that are circling
- >the earth on low polar orbits. The receiver works by receiving the
- >signals from any three of these satellites at a given moment (which is
- >guaranteed on any point on the earth, due to the orbital configuration
- >of the satellites). Therefore, you don't have to worry about access to
- >GPS signals no matter where you are; New York City or Tibet doesn't make
- >any difference.
-
- Well, actually about 24 satellites, but your general point is correct.
-
-
- --
- Carl Oppedahl AA2KW
- Oppedahl & Larson (patent lawyers)
- Yorktown Heights, NY
- oppedahl@patents.com
-
- ------------------------------
-
- Date: Sat, 6 Aug 1994 15:14:04 GMT
- From: ihnp4.ucsd.edu!news.cerf.net!mvb.saic.com!MathWorks.Com!europa.eng.gtefsd.com!gatech!wa4mei!ke4zv!gary@network.ucsd.edu
- Subject: GPS base stations in Scranton PA area?
- To: ham-space@ucsd.edu
-
- In article <oiEbZxa00WB6BAu24y@andrew.cmu.edu> Ergin Guney <eg23+@andrew.cmu.edu> writes:
- >
- >Excerpts from netnews.rec.radio.amateur.space: 4-Aug-94 GPS base
- >stations in Scrant.. by George Brown@partech.com
- >> Is anyone aware of any GPS base stations in the Scranton PA area? We have
- >> some survey work and are contemplating using a GPS receiver (need
- >> differential for better accuracy) to support the effort. We would like to
- >> know if there is a base station near, accuracy, cost of access, etc. Or
- >> is there another alternative that would give 1-2m accuracy in real-time?
- >> Any help would be appreciated.
- >
- >Either you have been misinformed, or I am missing something big. I
- >pretty well know that GPS signals aren't transmitted by any "base
- >stations" on land. They come from 12 or so satellites that are circling
- >the earth on low polar orbits. The receiver works by receiving the
- >signals from any three of these satellites at a given moment (which is
- >guaranteed on any point on the earth, due to the orbital configuration
- >of the satellites). Therefore, you don't have to worry about access to
- >GPS signals no matter where you are; New York City or Tibet doesn't make
- >any difference.
- >
- >Unless you're talking about some other GPS ("General Pinpointing
- >Service"? :) ) or a special land-based factor about GPS signals that I
- >wasn't aware of (like what you mean by "differential"), I am pretty sure
- >that what I have explained here is accurate.
-
- You're missing something pretty big. Differential GPS is the system
- whereby a GPS receiver at a known geographical benchmark continously
- broadcasts it's position via radio. Receivers in the field then
- combine the offset from known position reported by the benchmark
- receiver with their current satellite reported position to defeat
- the SA scatter deliberately introduced into the GPS satellite
- system by the military. Most GPS receiver manufacturers, like Garmin
- and Trimble, support differential GPS operation in their newer units.
-
- Benchmark transmissions are becoming more common. Some (sponsored
- by the FAA) are on commercial FM broadcast subcarriers, and others
- are on land mobile, marine, or amateur frequencies. The FAA and the
- Coast Guard are cooperating in setting up this system of benchmark
- receivers so that precision aircraft and boat navigation under zero-zero
- visibility conditions can be done. Some amateurs are also setting
- up benchmark systems for amateur navigation experiments. Instead
- of the typical civilian GPS navigational position uncertainty of
- 100 meters, differential GPS can offer position information accurate
- to a few centimeters. This is vital for zero-zero capability since
- few runways are over 100 meters wide. It's also vital in some shipping
- channels, for precision mapping, and for positioning of equipment
- such as offshore drill rigs. And it's obviously necessary for land
- vehicle navigation since most roadways are only 18 feet wide and
- lanes are only 9 feet wide. Errors of 100 meters are unacceptable.
-
- Gary
- --
- Gary Coffman KE4ZV | You make it, | gatech!wa4mei!ke4zv!gary
- Destructive Testing Systems | we break it. | uunet!rsiatl!ke4zv!gary
- 534 Shannon Way | Guaranteed! | emory!kd4nc!ke4zv!gary
- Lawrenceville, GA 30244 | |
-
- ------------------------------
-
- Date: Fri, 5 Aug 1994 13:47:40 -0400
- From: dog.ee.lbl.gov!agate!howland.reston.ans.net!gatech!newsxfer.itd.umich.edu!zip.eecs.umich.edu!panix!ddsw1!godot.cc.duq.edu!toads.pgh.pa.us!news.sei.cmu.edu!bb3.andrew@ihnp4.ucsd.edu
- Subject: GPS Freq and antenna questions
- To: ham-space@ucsd.edu
-
- Excerpts from netnews.rec.radio.amateur.space: 4-Aug-94 GPS Freq and
- antenna questions by Gary Delong@ctron.com
- > The questions: What freq range(s) do the GPS transmiters use?
- > and, is there anything "special" in the antennas made for
- > use with this units? ( circular pol? )
-
- Here is the only GPS frequency information that I have on hand. This is
- from a public domain frequency list named Scanner Searchers Guide by
- N5OWK dated January 1990, which I downloaded from this newsgroup or a
- similar one:
-
- 1575.42 MHz is the Navstar Global Positioning System (GPS)
- frequency L1, and 1227.6 MHz is L2.
-
- That's all it says. I hope this helps a little. But I won't be able to
- help you about the antenna at all, I'm afraid.
-
-
- Ergin Guney
-
- ------------------------------
-
- Date: Fri, 5 Aug 1994 00:06:50 GMT
- From: ihnp4.ucsd.edu!agate!howland.reston.ans.net!torn!nott!cunews!freenet.carleton.ca!FreeNet.Carleton.CA!ag381@network.ucsd.edu
- Subject: HELP NOAA Series
- To: ham-space@ucsd.edu
-
- Where can I find data on what these sats transmit ?I mean formal data useful
- for IR calibration and any other data such as perhaps telemetry data.
- Please post response and thanks in advance!
-
- ------------------------------
-
- Date: Fri, 5 Aug 94 14:48:01 GMT
- From: paperboy.ids.net!usenet@uunet.uu.net
- Subject: Low-band Satellite transponders?
- To: ham-space@ucsd.edu
-
- The Russian RS-10/11 and RS-12/13 satellites use 10 meter
- transceivers. A good description is in the "How to Use
- the Amateur Radio Satellites" booklet which I mentioned in
- a previous post.
-
- Philip Chien
- no sig yet
-
- In Article <CtyzFr.Hqy@usenet.ucs.indiana.edu>
- brandtk@silver.ucs.indiana.edu (Keith E. Brandt, MD) writes:
- >I have heard there are two amateur satellites that work entirely on the low-
- >bands (10 and 15 meters?). I would appreciate it if someone would let me know
- >which satellites and what the passbands are. If there is an archive somewhere
- >with this info, a pointer would be appreciated.
- >
- >Thanks,
- >Keith
- >
- >
- >===============================================================================
- >Keith E. Brandt, MD, WD9GET || Goodbye, cruel world that was my home-
- > New Castle Family Physicians || there's cleaner space out here to roam.
- > New Castle, Indiana || Put my feet up on the moons of Mars-
- >brandtk@silver.ucs.indiana.edu || sit back, relax, and count the stars.
- >===============================================================================
-
- ------------------------------
-
- Date: Sat, 6 Aug 94 19:38:37 GMT
- From: paperboy.ids.net!usenet@uunet.uu.net
- Subject: MacSPOC
- To: ham-space@ucsd.edu
-
- MacSPOC is an incredible program. I've used many versions up
- through version 1.5 and it's got features unavailable
- in any other satellite tracking program I've seen. You can
- input in an entire set of shuttle maneuvers, attitudes and burns
- and macSpoc will tell you where the shuttle will end up - and
- where it will be pointing! The program gives you a view out
- the window showing you where each window is pointed on the Earth's
- surface, and a simulated view which corresponds to the actual
- fieled of view out of the astronaut's window. On extremely useful
- feature for SAREX enthusiasts is the determinating of the point on
- the Earth's surface where the shuttle's SAREX antenna is pointing.
- For photography buffs the database include recommended shutter
- settings for different earth obs targets.
-
- The primary input for keplerian elements is in the M50 format, but
- Dan has also added the capability to accept two line elements from
- the standard Amsat format. One of the key features it is missing
- though is the capability to select a satellite from a text file of
- keps.
-
- The key limitation to MacSPOC is that it's so specifically designed
- for use by an astronaut in space (or a payload officer of flight
- dynamic officer on the ground) that it's fairly difficult to use -
- unless you're heavily into the shuttle program.
-
- In any case it's extremely impressive, and the shareware version
- is certainly worth looking at, even though it's an earlier version.
-
- How often can you say that you've tried software which has actually
- been used aboard the shuttle?
-
- Philip Chien KC4YER
- no sig yet - and yes I'm just a satisifed user without any financial
- interest in MacSPOC or Dan Adamo.
-
- ------------------------------
-
- Date: 5 Aug 1994 22:54:06 -0400
- From: newstf01.cr1.aol.com!search01.news.aol.com!not-for-mail@uunet.uu.net
- Subject: MacSPOC updates
- To: ham-space@ucsd.edu
-
- If there is enough of a desire to have them posted... I will post Dan
- Adamo's MacSPOC updates for the Shuttle missions as soon as they become
- available.
-
- Here is the skinny of the Mac program from the AOL files description:
-
- *** MacSPOC Info ***
-
- Welcome to an enhanced awareness of satellites in earth orbit! MacSPOC
- (SPOC = Spacecraft Personal Orbit Computations) v1.5 is a commercial real
- time satellite trajectory display. Previous MacSPOC versions were
- evaluated by orbiting astronauts during the STS-41, STS-43, and STS-52
- missions. MacSPOC continues to be used in control centers and schools
- across the country. The MacSPOCl v1.5 configuration regularly supports
- Mission Control planning for the Shuttle Amateur Radio Experiment (SAREX)
- program. A v1.1 package is available for downloading from AOL. It's
- similar to the MacSPOC version flown aboard STS-41 and is copyrighted
- freeware for you to "test drive".
-
- By downloading your MacSPOC test drive, you agree to two restrictions.
- First, you may not disassemble or modify MacSPOC code. Second, although
- you may produce unlimited copies of your download, it may not be
- distributed to others for any fee or compensation.
-
- Real world MacSPOC trajectory updates, called checkpoints, are uploaded
- during Space Shuttle missions and upon request. Because they're only
- about 500 bytes in size, checkpoints are easy to send and receive. To
- obtain free checkpoints, send your e-mail address via AOL to "AdamoD". If
- you'd also like to receive a free MacSPOC v1.5 brochure, include your name
- and mailing address too.
-
- Two functionally identical MacSPOC v1.1 download packages are available to
- support various Macintosh models. Choose the "MacSPOCfpu.sit" package
- only if your Macintosh has a 6888x FPU (math co-processor) chip. Other
- models, including 68040-equipped machines running with cache memory OFF,
- can utilize the "MacSPOC+.sit" package. Both packages are compatible with
- either System 6 or System 7.
-
- Your MacSPOC v1.1 download consists of four parts: the MacSPOC
- application, a world map bitmap file "SPOCMap", a database of STS-52 earth
- observation sites "Earth Obs", and a checkpoint formatting utility called
- "Convert2v1.1". To install MacSPOC v1.1 after your download is unstuffed,
- be sure at least the first three of these files reside in the same folder.
-
- A quick hypothetical demo of MacSPOC displays can be obtained with the
- following steps. First, if a file named "MacSPOC.cp" exists in the folder
- occupied by MacSPOC, delete it, rename it, or drag it elsewhere. Next,
- open (double-click) the MacSPOC application and await appearance of a
- dialog box with "Edit Liftoff GMT" as its heading. Click the "Check
- SV..." button, then click the "Save" button. A new dialog will appear,
- asking "Ready to Propagate State Vector?". Click the "Go!" button in this
- dialog, and you'll be off and running.
-
- At some point prior to tracking a real satellite like a Space Shuttle, you
- should be sure your Macintosh system clock is set accurately via the
- Control Panel. Next, select "Time Zone..." from MacSPOC's "Update" menu.
- Click the radio button which pertains to the time zone your system clock
- is keeping, then click the "Save" button. Unless you lose your copy of
- MacSPOC, you'll need to repeat this procedure only when you change time
- zones in your system clock, as when you "fall back" to standard time the
- last Sunday in October.
-
- All MacSPOC checkpoints are uploaded in v1.5 format. After downloading,
- you can translate a checkpoint to v1.1 format by using the Convert2v1.1
- utility. Just load Convert2v1.1, then use it to open the downloaded v1.5
- checkpoint. The checkpoint created by Convert2v1.1 can then be
- double-clicked or opened for processing by MacSPOC v1.1. The only
- information lost during this conversion process defines maneuvers which
- might be included to change the orbit originally defined in the
- checkpoint.
- -Dan Adamo,
- MacSPOC Developer
-
- ------------------------------
-
- Date: Sat, 06 Aug 1994 08:26:33 -0500
- From: europa.eng.gtefsd.com!NewsWatcher!user@uunet.uu.net
- Subject: MacSPOC updates
- To: ham-space@ucsd.edu
-
- In article <31uu0e$o95@search01.news.aol.com>, tstader@aol.com (TSTADER)
- wrote:
-
- > If there is enough of a desire to have them posted... I will post Dan
- > Adamo's MacSPOC updates for the Shuttle missions as soon as they become
- > available.
- >
- > Here is the skinny of the Mac program from the AOL files description:
- >
- > *** MacSPOC Info ***
- >
- > Welcome to an enhanced awareness of satellites in earth orbit! MacSPOC
- > (SPOC = Spacecraft Personal Orbit Computations) v1.5 is a commercial real
- > time satellite trajectory display. Previous MacSPOC versions were
- > evaluated by orbiting astronauts during the STS-41, STS-43, and STS-52
- > missions. MacSPOC continues to be used in control centers and schools
- > across the country. The MacSPOCl v1.5 configuration regularly supports
- > Mission Control planning for the Shuttle Amateur Radio Experiment (SAREX)
- > program. A v1.1 package is available for downloading from AOL. It's
- > similar to the MacSPOC version flown aboard STS-41 and is copyrighted
- > freeware for you to "test drive".
- >
- > By downloading your MacSPOC test drive, you agree to two restrictions.
- > First, you may not disassemble or modify MacSPOC code. Second, although
- > you may produce unlimited copies of your download, it may not be
- > distributed to others for any fee or compensation.
- >
- > Real world MacSPOC trajectory updates, called checkpoints, are uploaded
- > during Space Shuttle missions and upon request. Because they're only
- > about 500 bytes in size, checkpoints are easy to send and receive. To
- > obtain free checkpoints, send your e-mail address via AOL to "AdamoD". If
- > you'd also like to receive a free MacSPOC v1.5 brochure, include your name
- > and mailing address too.
- >
- > Two functionally identical MacSPOC v1.1 download packages are available to
- > support various Macintosh models. Choose the "MacSPOCfpu.sit" package
- > only if your Macintosh has a 6888x FPU (math co-processor) chip. Other
- > models, including 68040-equipped machines running with cache memory OFF,
- > can utilize the "MacSPOC+.sit" package. Both packages are compatible with
- > either System 6 or System 7.
- >
- > Your MacSPOC v1.1 download consists of four parts: the MacSPOC
- > application, a world map bitmap file "SPOCMap", a database of STS-52 earth
- > observation sites "Earth Obs", and a checkpoint formatting utility called
- > "Convert2v1.1". To install MacSPOC v1.1 after your download is unstuffed,
- > be sure at least the first three of these files reside in the same folder.
- >
- > A quick hypothetical demo of MacSPOC displays can be obtained with the
- > following steps. First, if a file named "MacSPOC.cp" exists in the folder
- > occupied by MacSPOC, delete it, rename it, or drag it elsewhere. Next,
- > open (double-click) the MacSPOC application and await appearance of a
- > dialog box with "Edit Liftoff GMT" as its heading. Click the "Check
- > SV..." button, then click the "Save" button. A new dialog will appear,
- > asking "Ready to Propagate State Vector?". Click the "Go!" button in this
- > dialog, and you'll be off and running.
- >
- > At some point prior to tracking a real satellite like a Space Shuttle, you
- > should be sure your Macintosh system clock is set accurately via the
- > Control Panel. Next, select "Time Zone..." from MacSPOC's "Update" menu.
- > Click the radio button which pertains to the time zone your system clock
- > is keeping, then click the "Save" button. Unless you lose your copy of
- > MacSPOC, you'll need to repeat this procedure only when you change time
- > zones in your system clock, as when you "fall back" to standard time the
- > last Sunday in October.
- >
- > All MacSPOC checkpoints are uploaded in v1.5 format. After downloading,
- > you can translate a checkpoint to v1.1 format by using the Convert2v1.1
- > utility. Just load Convert2v1.1, then use it to open the downloaded v1.5
- > checkpoint. The checkpoint created by Convert2v1.1 can then be
- > double-clicked or opened for processing by MacSPOC v1.1. The only
- > information lost during this conversion process defines maneuvers which
- > might be included to change the orbit originally defined in the
- > checkpoint.
- > -Dan Adamo,
- > MacSPOC Developer
-
-
- Can this program be found anywhere else besides AOL, like maybe at some
- of the popular FTP site's (ie SUMEX,UCSD,OAKLAND ) ????
-
-
-
- *********************************************
- Keith J Leite AA1JF
- AX25 - AA1JF @ WA1PHY.#EMA.MA.USA.NA
- AMPR - aa1jf@switch.sema.ampr.org
- Internet - kleite@gtec3.ndhm.gtegsc.com
-
- **********************************************
-
- ------------------------------
-
- Date: 5 Aug 1994 22:49:06 -0400
- From: newstf01.cr1.aol.com!search01.news.aol.com!not-for-mail@uunet.uu.net
- Subject: STS-65 Commemorative TLI Burn
- To: ham-space@ucsd.edu
-
- I am re-posting this note from a message I got on AOL. Please reply
- directly to Dan Adamo at his AOL account: Adamod@aol.com
-
- Text follows:
- =================
- Date: Thu, Aug 4, 1994 7:43 PM EDT
- From: Adamod
- Subj: STS-65 Commemorative TLI Burn
-
- File: TLI.sit (58540 bytes)
-
- MacSPOC Users-
-
- During STS-65, you'll recall MacMission Control supported targeting of a
- commemorative TransLunar Injection (TLI) burn. Time of IGnition (TIG) for
- this burn was 25 years to the minute after a similar TLI was performed by
- Apollo-11 to break free of low earth orbit. The commemorative TLI was
- tageted to reach a point 100 miles above the moon's farside 25 years to
- the minute after Apollo-11's Lunar Orbit Insertion (LOI) burn TIG.
-
- With targets from MacMission Control, Flight Dynamics Officers (FDOs) in
- the real Mission Control filled out a Pre-Advisory Data (PAD) for the
- commemorative TLI burn. This PAD, together with plots of STS-65's
- post-TLI trajectory relative to the earth and moon, are enclosed as 3
- TeachText documents for your viewing pleasure.
-
- An image of the commemorative TLI PAD was uplinked as a FAX to the STS-65
- crew around 8:30 AM CDT July 16, 25 years after Apollo-11 was launched.
- Upon receiving the PAD, STS-65 Commander Bob Cabana remarked, "Don't we
- wish!" Powered Explicit Guidance mode 7 (PEG 7) targets computed by
- MacMission Control appear on the PAD as an in-track speed increase of
- 9586.3 fps, a northward cross-track velocity change of 3073.7 fps, and a
- radial upward velocity change of 5944.0 fps. Using both Orbital
- Maneuvering System (OMS) engines for a total thrust of 12000 lbs, Columbia
- would have required a TLI burn duration (TGO) of 2 hrs 03 min 24 sec to
- build up these velocity changes. Actual OMS fuel available to Columbia at
- TLI TIG would have supported less than 5 min of 2-engine burn time, and
- most of this was allocated to STS-65 deorbit.
-
- It's worth noting Apollo-11 weighed nearly 200000 lbs at TLI TIG, only
- about 45000 lbs less than Columbia's WT on the commemorative PAD. Unlike
- Columbia, however, about 75% of Apollo-11's weight was propellant to feed
- the Saturn IV-B's single J-2 engine during TLI. Because the J-2 developed
- about 200000 lbs of thrust, Apollo-11's TLI required less than 6 min to
- perform.
-
- The 2 post-TLI plots are in the ecliptic plane. This is coincident with
- earth's orbit around the sun. The moon's orbit about earth is less than 5
- deg from the ecliptic. The Vernal Equinox indicated on these plots is the
- Sun's apparent position as viewed from earth when Spring begins in March.
- The Sun's position in mid-July is also indicated on the plots.
-
- Does anyone have a guess as to when the next (manned) TLI burn will be
- performed for real?
-
- -Dan Adamo
- ====================
- a file was attached which I will be glad to BinHex and e-mail to anyone
- that would like it.
-
- 73 for now.... c u on the shortwaves
- Terry Stader - KA8SCP
- America Online Ham Radio Club Host
- Internet: tstader@aol.com (files <28K) or
- p00489@psilink.com ( files >28K)
- KA8SCP@WA1PHY.#EMA.MA.USA.NOAM
-
- ------------------------------
-
- Date: 6 Aug 1994 06:23:03 -0400
- From: newstf01.cr1.aol.com!search01.news.aol.com!not-for-mail@uunet.uu.net
- Subject: What SAT's can I hear on a Scanner ?
- To: ham-space@ucsd.edu
-
- In article <2t2qdt$dih@freenet3.scri.fsu.edu>, bmm1@freenet3.scri.fsu.edu
- (Bruce M. Marshall) writes:
-
- Do you ever run packet? Or catch weather pics? I'm working on the no code
- right now and would like input on the above subjects.
- Thanks.
- 73
- John
-
- ------------------------------
-
- End of Ham-Space Digest V94 #217
- ******************************
-