home *** CD-ROM | disk | FTP | other *** search
-
- RECEIVING WEATHER SATELLITE IMAGERY: A BEGINNER'S PRIMER
- --------------------------------------------------------
-
- Courtesy Dallas Remote Imaging Group
- Datalink RBBS ============> 214-394-7438
-
- Dedicated to satellite tracking, decoding of NOAA/Soviet
- meteorological satellite telemetry, and Digital Image
- Processing of satellite pictures.
-
- Jeff Wallach, N5ITU, Chairman
-
- John Williams, Co-Chairman
- John DuBois, W1HDX, VAS/HRPT Design Engineer
- T S Kelso, Air Force/NASA liason
- Ed O'Grady Soviet Space Program Analyst
- Jim Blocker, KF5IW, Director Software Development
- Jose Sancho WB5YFU, Director of Engineering
-
- All aspects of Amateur Radio covered on Datalink RBBS
-
- (IF YOU COPY THIS BULLETIN FOR OTHER SYSTEMS, PLEASE BE KIND ENOUGH
- TO LEAVE THIS BANNER AS DUE CREDIT TO THE HARD-WORKING FOLKS WHO
- DEVELOPED AND CONTINUALLY UPDATE THIS INFORMATIVE 'HOW-TO'BULLETIN)
-
- Dayton HamVention '89
- (rev 10)
-
- Tom Gentry, K5VOU, has been kind enough to help us prepare the
- following:
-
- HOW TO RECEIVE APT PICTURES FROM THE NOAA SATELLITES
- ----------------------------------------------------
-
- So you have decided you want to receive the NOAA and Russian METEOR
- orbiters and you have a radio that receives 137.500 MHz and a
- computer. So now what do you do? I hope this short dissertation will
- steer you in the correct direction.
-
- To display a picture from the orbiting birds you need several things.
- First you need to 'acquire' the satellite. This means you need the
- program to calculate its position at any time and determine if you can
- hear the signals from the 'bird'. The best place to get this program
- is probably AMSAT-NA an organization dedicated to AMateur SATellites.
- They have several very good tracking programs for the IBM and also for
- Commodore and Apple as well. After you have acquired the program and
- have it running on your computer, you then need the Keplerian Elements
- for the NOAA satellites. These elements as well as some tracking
- programs are available from the CELESTIAL RCP/M, run by TS Kelso, at
- 513-427-0674 (Fairborn,OH) and from the Weather Fax and Remote Imaging
- DATALINK BBS run by Dr. Jeff Wallach, N5ITU as bulletins for some 80 +
- sets of satellite data. Another bulletin also tells you to what the
- printed numbers correspond so you can enter them into the computer
- program. Use the newest elements you can find as the orbiting
- satellites are subject to forces which change their orbits. If you use
- Keplerian Elements more than 3 or 4 weeks old, your chances of hearing
- the bird are reduced.
-
- Once you are tracking the birds you should hear them on your receiver.
- They will be on 137.62 (NOAA-11), 137.500 (NOAA-10), 137.850 (Meteor
- 3-2), 137.4 (Meteor 2-16), 137.3 (Meteor 2-17 and 2-18). Now comes the
- first thing different about NOAA orbiters. The frequency deviation of
- the FM transmission is about +/-18-20 kHz. This is 4 times the normal
- deviation of a police call and 1/3 the deviation of the FM broadcast
- band FM signal. If you receive the signal on the regular
- communications width of the scanner the light areas of the picture
- will be noisy and the signal will sound distorted and the picture will
- basically be useless. If you use the FM broadcast bandwidth (assuming
- your scanner will let you), the signal will be weak and there may be
- too much background noise to see the picture.
-
- So what now ? Well there are two ways to fix the problem, find a
- receiver with the proper I.F. bandwidth filter of 50 kHz, or modify
- the I.F. of your scanner to about 50-80 kHz. The simplest mod which
- has been found to be workable is to remove the narrow communications
- I.F. filter and replace it with a 0.01 uFd capacitor. This provides
- for good Wefax pictures from GOES and pretty fair NOAA orbiter
- pictures. It can of course result in retuning the radio, voiding the
- warranty and making the squelch not work properly.
-
- The other characteristic of the NOAA satellite transmissions is THEY
- ARE WEAK. To get good pictures over a large area we have found a
- pre-amplifier to be essential. A GaAs-FET type can be obtained from
- various sources at a reasonable price but still about 50-100 dollars.
- You can also build one for about 25 dollars from plans for a pre-amp
- for the 2-meter amateur band and tune it to 137.5 easily.
-
- Lastly, but importantly, the antenna can be of an omni directional,
- uniform pattern type such as a turnstile antenna similar to those used
- in the FM broadcast reception business but of course tuned to 137.5
- MHz. Mount the pre-amp at the antenna if possible. Crooked coathangers
- on broomsticks have been known to work, and it is not difficult to
- build the antenna. Of course 2-meter beams with Az/El tracking will do
- the job well.
-
-
-
-
-
-
- Now that you have a nice audio signal from the satellite, what happens
- next? The audio tone of 2400 HZ which is the carrier tone that is used
- to carry the picture information (video), must be detected and the
- video data converted from analog to digital and then displayed on the
- computer monitor by the software. The hardware and software to do this
- is available from several sources with more coming along. Several
- stand-alone boxes are also available that produce some form of
- computer output either in printed form or on the display. In addition
- the people on the DATALINK BBS may also have some data to share with
- you regarding this equipment.
-
- One of the best sources for information is the WEATHER SATELLITE
- HANDBOOK available from Dr. Ralph Taggart of Michigan State University
- at 602 S. Jefferson, Mason, MI 48854 for $15.00. Taggart also writes
- the monthly WEATHERSAT column which appears in '73 Magazine. A must is
- THE JOURNAL OF THE ENVIRONMENTAL SALELLITE AMATEUR USERS' GROUP -
- JESAUG - which is published quarterly. It is available for $24.00 per
- year from the editor, Greg Mengell, 2685 Ellenbrook Drive, Rancho
- Cordova, CA 95670. Back issues of the JESAUG are also available.
-
- At the present the simplest software for the IBM is the Elmer
- Schweittek MULTIFAX software. A hardware kit is available from A&A
- Engineering which includes the video dectector circuit and A/D
- converter. Input to the PC is via the game port. If you want to build
- your own, complete documentation to build an interface circuit on an
- IBM PC prototyping board is available from H. Paul Shuch, N6TX, for
- $6.00 - FAXBOARD.
-
- The WEPIX(tm) software and hardware is available from Encomm. It will
- produce pictures of 1200 lines by 800 samples per line displayed at
- 640 x 350 pixels in 16 shades of gray or 16 colors using an IBM PC
- with 640kB, EGA card and at least one 360k disk.
-
-
-
- 'Typical' APT Receiving Station
- -------------------------------
-
-
- [1] ANTENNA
- -
- [2] PRE-AMP
- -
- -
- -
- - [ STAND ALONE UNITS ]
- -
- [3] RECEIVER -----------------> FAX MACHINE ---> PAPER
- - WRASSE UNIT ---> MONITOR
- - YU3UMV UNIT ---> MONITOR
- - - - - VCR
- -
- -
- -
- [4] - VIDEO DETECTOR -
- - -
- - -
- [5] - ANALOG/DIGITAL -
- - -
- - - [ SCAN CONVERTERS ]
- - -
- [6] - INTERFACE TO PC - <=======> ROBOT 1200
- - - TAGGARTS'S WSH
- - - IMAGEWISE
- - -
- [7] - SOFTWARE - ** SECOND DISPLAY **
- - - for weather images
- - -
- - -
- [8] - GRAPHICS ADAPTOR -
- -
- -
- -
- -
- [9] PC DISPLAY / MONITOR
-
- Display weather images
- (or commands for SCAN CONVERTERS)
-
-
- [10] PC PRINTER / DOT MATRIX / LASER
-
-
-
- NOTES:
- ------
-
- [4] VIDEO DETECTOR, [5] ANALOG/DIGITAL CONVERTER, and
- [6] INTERFACE TO PC may be in seperate hardware units
- or all on one circuit board.
-
-
-
-
-
- Sources:
- ----------------------------------------------------------------------
-
- NOAA Data / Keplerian Elements:
-
- DATALINK RBBS, N5ITU, Dr. Jeff Wallach, 214-394-7438,
- DALLAS REMOTE IMAGING GROUP ELECTRONIC BULLETIN BOARD
- UPDATES ON NOAA BULLETINS, SATELLITE LAUNCHES, FREQUENCIES
- DISPLAY PICTURES FROM NOAA SATELLITES ON YOUR OWN P.C.
-
- CELESTIAL RCP/M, TS Kelso, 513-427-0674, NASA Prediction Bulletins |
- are online and updated several times weekly |
-
- Satellite Tracking Software:
-
- AMSAT-NA, PO Box 27, Washington, DC 20044, Software Exchange,
- phone 301-589-6062 (voice), N4HY - QUIKTRAK, W0SL - ORBITS II,III,IV
- Roy D. Welch, W0SL, 908 Dutch Mill Drive, Manchester, MO 63011,
- phone 314-391-1127, ORBITS II-EGA, ORBITS III-EGA, ORBITS IV-VGA |
- DATALINK BBS, download SATTRAKx.ARC, SEESATxx.ARC and others
- CELESTIAL RCP/M, TS Kelso, 513-427-0674, SATTRAKx.ARC or SEESATxx.ARC |
- Astronomical Data Service, Rodger Mansfield, 3922 Leisure Lane,
- Colorado Springs, CO 80917-SPACE BIRDS program and Newsletter, $40.
-
- Receivers:
-
- Vanguard Labs, 196-23 Jamaica, Hollis, NY 11423,
- phone 718-468-2720
- Hamtroincs, Inc.,65-D Moul Road, Hilton, NY 14468-9535
- phone 716-392-9430
- DARTCOMM, Mr. N. Hearn, DARTCOMM Ferndale, Postbridge, Yelverton, |
- Devon PL20 6SY, Great Britain, UK, phone 011 44 0822 88253 |
-
- Crystals:
-
- JAN Crystals, 2400 Crystal Dr, Fort Myers, FL 33906-6017,
- phone 1-800-237-3063 or 813-936-2397
-
- Pre-Amps:
-
- THL/Encomm, Inc, 1506 Capital Ave, Plano, TX 75074, phone 214-423-0024
- Spectrum International,Inc., Box 1084, Concord MA 01742,
- phone 617-263-2145
- Vanguard Labs, Hamtronics and GLB for Helical RF Filters for intermod
- Ehrler-DuBois Very High Performance LNA for 1500-1750 Mhz, contact |
- Greg Ehrler or John DuBois via DATALINK |
-
- Antennas:
-
- ARRL Handbook, 1986, turnstile over ground antenna.
- ARRL Satellite Experimenter's Handbook by Martin Davidoff, K2UBC
- Modern Electronics, September 1988, Hank Brandli article, page 82,
- Receiving Satellite Weather Photos
-
- Hardware Interface to PC:
-
- A&A Engineering, 2521 W. La Palma, Unit K, Anaheim, CA 92801,
- phone 714-952-2114 - both AM dectector and A/D converter, input to PC
- via game port (4-bits) or parallel I/O Interface (8-bits) - kit is
- $50. - assembled and tested unit is $70.
- Microcomm, H. Paul Shuch, N6TX, 14908 Sandy Lane, San Jose, CA 95124,
- phone 408-377-6137 - FAXBOARD - A Weather Facsimile Display Board for
- the IBM PC - Complete documentation to build your own interface
- circuit on an IBM PC prototyping board - video and an 8-bit A/D
- interface - $6.00
-
- Video Detectors:
-
- RTM Circuit Boards, 205 Elm St.,Van Horne, IA 52346-0400,
- video detector (the 'Wilson Board') see QST Magazine, Jan '86 and
- Vince Coppola's article in Oct 1988 73 Magazine
- QST Magazine, August 1985, Grant Zehr article, page 27, video detector
- circuit
-
- A/D Converter & Parallel I/O Interfaces for the IBM PC:
-
- MetraByte, 440 Myles Standish Blvd., Taunton, MA 02780, Model PIO-12
- board for the IBM PC, phone 617-880-3000
- John Bell Engineering, Inc, 400 Oxford Way, Beimont, CA 94002,
- phone 415-592-8411
-
-
-
-
-
- Sources:
- ----------------------------------------------------------------------
-
- Display Software and Hardware - 'Amateur':
-
- Encomm, Inc. 1506 Capital, Plano, TX 75074, WEPIX(tm) system,
- phone 214-423-0024
- Multifax, Elmer Schwittek, 2347 Coach House Lane,Naples, FL 33942,
- phone 813-434-2268 - Multifax 3.3 for EGA, 2.x for CGA on the IBM-PC |
- Clay Abrams Software, 1758 Comstock Lane, San Jose, CA 95124, software
- for the ROBOT 1200 - see QST Magazine, Jan '86
- Ralph Taggart, 602 S. Jefferson, Mason, MI 48854, Weather Satellite
- Handbook Scan Converter - for the Radio Shack CoCo3 - see 73
- Magazine, Nov '84 and Dec '84 and Handbook. Ralph Taggart also writes
- the WEATHERSAT column for 73 Magazine.
- ImageWise Display/Receiver, Circuit Cellar Inc. - Micromint Inc.,
- 4 Park Street, Vernon, CT 06066, phone 203-875-2751 - BYTE Magazine,
- May, Jun, Jul, Aug 1987. JESAUG 88-2 and Oct 1988 73 Magazine have |
- information on how to build the video and A/D interface. Ver 2.0 |
- software supports VGA graphics and 640 samples per line at 64 gray |
- levels. With VGA the ImageWise Display unit is not required. The |
- software is available for $29.95 from Vince Coppola, N1VC, 6 Bobbin |
- Road, Terryville, CT 06786 |
- ASAT: An Apple-based Satellite Imaging System by Grant Zehr, WA9TFB -
- QEX Magazine, March '88 - has complete information to build an
- excellent unit using the APPLE with a Redshift Ltd graphics card
- giving 256 * 256 pixels at a full 256 levels of gray.
-
- AMIGA Imaging Software - Dallas Remote Imaging Group |
- PO Box 118053 |
- Carrollton, TX 75011-8053 |
- Voice 214 394 7325 |
- Uses standard Amiga hardware - no special display |
- Powerful NASA digital enhancement curves built-in |
- Digital image processing capabilities |
- Uses A&A Engineering $49 demodulator |
- Image saved for use by other graphics programs |
- Full histogram analysis |
- Full 8 bit data is stored on diskette or hard disk |
- Unattended operation |
- Can be setup in 30 minutes |
- Call for special pricing |
-
- IBM-PC Interface Card and Software - Jim MacLean and Paul Atkinson, |
- 2112 Parsons Avenue, Melbourne, FL 32901, 407-727-3646 - plug in card |
- for IBM XT or AT, 9600 samples/second at 8 bits, automatic |
- synchroniztion for NOAA, METEOR and WEFAX, data saved realtime to |
- hard disk, supports CGA, EGA, and VGA, $300 for hardware and software |
-
- Complete Systems - Hardware and Software:
-
- Dallas Remote Imaging Group |
- P.O. Box 118053 |
- Carrollton, Texas 75011-8053 |
- 214 394 7325 |
- Complete Earth-Scan Amiga turnkey system ready to put on air |
-
- Greg Mengell, 2685 Ellenbrook Drive, Rancho Cordova, CA 95670,
- APT Associates, phone 916-364-1572, Wraase System, FAX recorders, and
- hi-end, commercial units.
- (Ask for DEPT. J. == Specify referral by Dallas Remote Imaging Group)
- YU3UMV Digital Storage and Scan Converter for Weather Satellite
- Images, described in VHF Communications Magazine, Winter 4/82 and
- Spring 1/83 - Modifications are described in the Satellite Users'
- Group Journal - JESAUG - available from Greg Mengell. Back issues of
- VHF Communicatons and the YU3UMV printed circuit boards are available
- from Fred Sharp, TimeKit, P.O. Box 22277, Cleveland, OH 44122, phone
- 216-464-3820.
- Marta Systems, 209 W. Santa Paula St, Santa Paula, CA 93060,
- phone 805-933-1270, 'Live From Space' for the AMIGA PC - $500.+
- Loren Johnson, P.O. Box 219, Cleveland, MN 56017, system for the
- IBM-PC - $750, phone 507-931-4849
- WEATHERTRAC[tm] IBM-PC Based Satellite Image Acquisition and Animation |
- System - $1885 for EGA - $3495 for VGA, Fred Bartlett, Softworks, |
- Inc, Allentown, PA, phone 215-395-4441 or George Isleib, Lehighton,
- PA, phone 717-386-4032
- TRUfAX by CompuMAX IBM-PC based facsimile system - $600, Compumax
- Corporation, 26 West Boylston Street, West Boylston, MA 01583, phone
- 617-835-2722
-
- Satellite Meteorology:
-
- Satellite Imagery Interpretation for Forcasters - a 3 volume set |
- published in 1985 for NOAA now available from the National Weather |
- Association, 4400 Stamp Road, Room 404, Temple Hills, MD 20748, |
- 301-899-3784, $32 for members, $45 for non-members ( Membership is |
- $20. ) |
-
-
-
- Bibliography - Online DATALINK Bulletins: (214 394 7438 -- BBS)
-
- NASA Satellite Prediction Bulletins, NASA-PB.xxx
- How to use NASA 2-Line Keplerian Elements
- AMSAT Bulletins and Weekly Notes / Orbital Elements
- NOAA APT NOTES
- NOAA User Bibliography
- Summary of Soviet Meteorological Satellites by Grant Zehr
- How to Build a Weather Satellite Groundstation (This Primer)
- Wrasse Dedicated System Review
- GOES VAS Imaging System for the IBM PC, John DuBois W1HDX |
- LNA for WEFAX-VAS-HRPT-GPS, John Dubois and Greg Ehrler |
- GOES WEFAX Information Note 89-W1 (3/89) |
- GOES I-M Converence Summary |
- Dallas Remote Imaging Group online Image Files |
-
- Review DATALINK RBBS bulletins for current information ====> 214 394-7438
-
-
- DALLAS REMOTE IMAGING GROUP - DRIG Voice: 214 394-7325
- Data: 214 394-7438
- P.O. Box 118053
- Carrollton, TX 75011-8053
- ATTENTION: Jeff Wallach, Chairman
-
- |
- New or Changed Items = |
- |
-