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Slow Scan Television Explained

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Slow Scan Television Explained Slow Scan Television Explained By Mike Wooding G6IQM Acknowledgements The Editors wish to thank the following people for their help with the production of this book, for their supply of information and detail and, in the case of Kim, Ashley and Michelle, for putting up with all the disruption caused by the production of a book in a working home and for all their support and encouragement. John Wood G3YQC B. A. Smith G3WCY Martin Emmerson G3OQD Peter Asquith G4ENA Roland Humphries G4UKL Trevor Brown G8CJS C. Grant Dixon G8CJK Peter Lockwood G8SLB Jean-Jaques Noel F6ILR Daniel Caudroy F6BXC The author also wishes to thank the Authors and Publishers of the various works to which reference has been made. This special A4 sized edition edited by Ian Pawson, August 1998 Editors note: This book was originally printed A5 size. This version has the same content, but has been rearranged to A4 size. The quality of some of the diagrams and pictures is not up to our usual standard as they have been scanned in from an original paper copy. ISBN 0-9513779-3-0 Slow Scan Television Explained Page 1 Contents Contents Acknowledgements............................................................................................................................................................................... 1 Contents ................................................................................................................................................................................................. 2 Foreword................................................................................................................................................................................................ 5 Introducing Slow Scan Television ....................................................................................................................................................... 6 Introduction..............................................................................................................................................................6 The Basics of a Slow-Scan Picture ..........................................................................................................................6 Receiving Slow-Scan Television .............................................................................................................................7 Equipment................................................................................................................................................................7 Computerised SSTV ................................................................................................................................................9 Transmitting Slow-Scan Television.........................................................................................................................9 Picture Sources ......................................................................................................................................................10 Commercial Systems .............................................................................................................................................11 Software Systems...................................................................................................................................................12 References..............................................................................................................................................................13 Modes and Systems............................................................................................................................................................................. 14 Monochrome SSTV Modes ...................................................................................................................................14 Colour SSTV Modes..............................................................................................................................................15 Slow Scan Television Techniques ..................................................................................................................................................... 20 The SSTV Studio...................................................................................................................................................20 Lighting..................................................................................................................................................................20 Setting up...............................................................................................................................................................21 SSTV in Colour .....................................................................................................................................................22 Principles ...............................................................................................................................................................22 Colour SSTV using a Black and White Camera ....................................................................................................22 Colour SSTV using a Colour Camera....................................................................................................................23 Scan Conversion Techniques.................................................................................................................................24 Fast to Slow ...........................................................................................................................................................24 Slow to Fast ...........................................................................................................................................................26 References..............................................................................................................................................................27 Commercial SSTV Equipment........................................................................................................................................................... 28 Robot Research Inc. Model 1200C........................................................................................................................28 Robot 450C............................................................................................................................................................29 Robot 400 ..............................................................................................................................................................29 Robot 400C............................................................................................................................................................30 Robot 300 ..............................................................................................................................................................30 Robot 70 ................................................................................................................................................................31 Robot 70D only:.....................................................................................................................................................31 Robot 70 Accessories.............................................................................................................................................31 Model 800 Keyboard .............................................................................................................................................32 Robot 800C............................................................................................................................................................32 Davtrend Ltd. Model DRAE SSTV Television Transceiver..................................................................................33 Wraase Elektronik Model SC-1 .............................................................................................................................34 Spacemark SSM-1 .................................................................................................................................................34 Venus SS2..............................................................................................................................................................35 The G3WCY Digital Scan Converter................................................................................................................................................ 36 Principles ...............................................................................................................................................................36 Operation of the Analogue-To-Digital Board........................................................................................................36 Operation of the Digital Memory Board................................................................................................................36 Power Supply.........................................................................................................................................................38 Construction...........................................................................................................................................................38 Setting-Up And Calibration ...................................................................................................................................38
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