Tune the hidden signals on satellite TV : the secret signals on satellite TV

220 Pages·1995·34.91 MB·English

by  Harrington, Thomas P.

TUNE THE HIDDEN SIGNALS
ON SATELLITE TV
THE SECRET SIGNALS
ON SATELLITE TV
THIRD EDITION
THOMAS P. HARRINGTON W80MV
PUBLISHED AND DISTRIBUTED BY
UNIVERSAL ELECTRONICS, INC.
4555 Groves Road,Suite 13
Columbus, Ohio 43232,U.S.A.
614-866-4605
FAX [phone]
PLEASE NOTE
This work is published for the commercial field toincrease
their awareness ofthe many non-video opportunities exist
ing in the satellite communications field. The publisher and
its author do not condone any individuals, company or
groups misuse ofany ofthis information in any way.
Section 605 of the Communications Act of 1934, as
amended, generallywarns you that non-broadcast-classcom
munication signalsareconsidered 'private' communications.
The 1934act wasdesignedtoestablishguidelinesto prevent
unauthorized'thirdparties'[Le.,anyonenotassociateddirectly
with the'privatecommunications')from setting out tointercept
such private communications.Section 605warns that anyper
son not authorized to intercept such transmissionsand who
does so, eitheron purposeon accidentally,shall not divulge
to any otherpartyany of the following: (a)that such atrans
missionexists,(b)thecontentofthetransmission'intercepted'.
Inanothersectionof the FCCrules, the FCCTreats almicro
wave[Le.,satellite) communicationsinthe3.7to4.2GHzband
as'commoncarrier'transmissions,andthereafterconfirmsby
definitionthatallcommon carriertransmissionsareconsidered
non-broadcast[asin private) transmissions. Theserules were
adoptedatatime when the primaryconcernwaswith 'eaves
dropping' on privateoverseasand domestictelephone com
municationsandInstudyingthedebate oftheeraitwouldap
pear that the real concern was with employeesof the telcol
commoncarrierwho mighthaveaccess intheirworkroutines
to these circuits.TheCongressclearlywas worriedprimarily
about commoncarrieremployeeseavesdropping.Inthe Inter
vening 46 years the whole nature of communications has
changed including the use of some common carrier trans
mission frequencies for non-common carrier type signals.
ISBN #0-916661-04-0
Copyright MCMXCIIbyUniversalElectronics, Inc.Allrightsreserved.Nopartofthisbookmaybereproducedor
reprintedorusedinanyformbyanyreproduction means,includingphotocopy, mechanicalorrecording without
permission inwritingfromthepublisher.
PrintedintheUnitedStatesofAmerica.
-- ----
---
ACKNOWLEDGMENTS
We wish to thank the many companies and
individuals who furnished us with reference
materials and photographs:
GTE, for the full-color cover photo, - The Harris Corp.
Comtech Data Corp. - Microdyne Corp. - Avcom of
Virginia, Inc.- SouthernSatelliteSystems, Inc.- Wegener
Communications Co. - Leaming Industries, Inc.
Videostar Connections, Inc. - Equatorial Communica
tions Co. - Genesis Research Corp. - R. L. Drake Co.
Digital Electronic Systems - Conifer Corp. - Macom,
Maca, Inc. - Paradigm Manufacturing - United Satellite
Systems - Westat Communications - Japan Radio Co.
- Trio-Kenwood - Hughes Communications - Mark L.
Lewis for Teletext Section - Reuters - Commodity Com
munications Corp.- Satellite Syndicated Systems, Inc.
Bonneville Telecommunications - Scientific Atlanta, Inc.
- United Video, Inc. - Dow-Jones Cable News - SSS
Cable Text - Modulation Associates, Inc. - Winegard
Company - RCA-A. T. & T. - Dick Smith Electronics
Mark Long- CommTeck, Inc.-Apple Computer- Dave
Kelce - John Fellin - DTN
Prater Design & Graphics
"Thepublic'stax dollars were criticalto the developmentofsatellite communications."
Senator Barry M. Goldwater
ii
PREFACE
Mostsatellitesandtheirtranspondersareknown Section605oftheCommunicationsActof1934,
bytheirvideotransmissions,however;satellitesalso as amended, generally warns that non-broadcast
carrylargeamountsofnon-videoproductsthatrange class communication signals are considered "pri
from audio newsservices,newsteletypewriterchan vate"communications. The 1934act was designed
nels, high speed data systems, long distance tele toestablishguidelinestopreventunauthorized"third
phone circuits, teletext services, stock market re parties"(t.e.,anyonenot associateddirectlywith the
ports, business data channels, plus many other "private communications") from setting out to inter
types of services. ceptsuchprivatecommunications.Section605warns
Most satellite receive-onlyownersareawareof that any person not authorized to intercept such
the many additional audio channels available on transmissionsandwhodoesso,eitheronpurposeor
theirreceivers equippedwith tunable audio subcar accidentally, shall notdivulgeto any otherpartyany
rier sections. A popularaddition to a well-equipped of the following: (a) that such atransmission exists,
TYROsetupisaqualitystereo tunerwhichtunesthe (b) the content of the transmission intercepted. In
stereo audio contained in the subcarrier section of anothersectionof the FCC rules, the FCC treats all
the satellite signal. These signals are in addition to microwave (Le.,satellite)communicationsinthe 3.7
the regular video programs audio section which is to4.2GHz band as"commoncarrier" transmissions,
contained withinthis full subcarriersection. andthereafterconfirmsbydefinitionthat allcommon
In"HIDDEN SIGNALS,"we will look at most of carriertransmissionsareconsiderednon-broadcast
the non-video signalsonthe varioussatellites.Many (as in private) transmissions. These rules were
ofthesecan be receivedwith simple, readily-obtain adoptedatatimewhentheprimaryconcernwaswith
able equipment. Other types of services require "eavesdropping"on private overseas and domestic
complex computer and microprocessors to obtain telephone communications. In studying the debate
the propersignal and receive intelligiblecopy.Most ofthe era, itwouldappearthat the real concernwas
ofthese hi-tech serviceswill beoutlinedandcovered with employees of the telco/common carrier who
inthis book. might have access in their work routines to these
Please beadvisedthattheCommunicationsAct circuits. The Congressclearlywasworriedprimarily
of 1934, Section 605, which covers the rules and aboutcommoncarrieremployeeseavesdropping.In
regulationsfor the interceptionofallprivatecommu the intervening46yearsthewholenatureofcommu
nications broadcast over (RF) radio frequencies, nications has changed, including the use of some
applies to interception from satellite transmissions common carrier transmission frequencies for non
aswell.Contentsofthesetransmissionsarenottobe commoncarriertype signals.
divulged to anyone.
iii
TABLE OF CONTENTS
PREFACE PAGE III CHAPTER 4 PAGE 71
SINGLE CHANNEL PER CARRIER (SCPC)
CHAPTER 1 PAGE 1 FM/SCPC-What IsIt? 71
UNDERSTANDING THE SATELLITE SIGNAL Radio Networking 71
Modem Methods of Communications 1 The System 75
Multiple Audio and Data Subcarriers 4 SCPC/FM Equipment. General 80
Various Types of Satellite Transmissions 4 Harris Corporation 80
The Satellite Signal Spectrum Harris SCPC/FM Networks 80
From 0to 30,000 MHz 4 Receive-Only Networks 80
Satellite Spacing Plan 7 TDMA InBrief 82
Brief History of U.S. Satellite Communications 9 Harris TDM Networks 82
Where the "Hidden Signals"are Located 10 Microdyne Corporation 87
Comtech Data Corporation 91
CHAPTER 2 PAGE 25 Avcom ofVirginia, Inc. 92
AUDIO SUBCARRIERS(SBC/FM) How to Receive International
Audio Subcarriers on Satellite TV 25 Satellite Audio on SCPC 98
Where to Find the Audio Subcarriers 26 Narrow Band SCPC Equipment 98
Equipmentto Receive AnotherNarrow Band
Stereo Audio Subcarriers 29 SCPC-FM/SCPC/FDM Service 99
Four Basic Stereo Formats Used Multiplexing and Frequency Division
on Satellite Transponders 37 Multiplexing (FDM) 99
Matrix-Multiplex and Discrete Formats 38 How to Set UpTo Receive
Optimizing Subcarriers FM/SCPC/FDM Data Services 103
for Satellite Transmission 41 What IsTeletype (RnY)? 103
A Further Look atSatellite Subcarriers 44 A User-Friendly FM/SCPC Receiver 106
"In-Touch" Reading Service 50 Build an FM/SCPC System
GalacticlTempo Sound 50 for Under $100.00 107
Where to Find SCPCServices 113
CHAPTER 3 PAGE 53 ASummaryof SCPC 114
SATELLITETELEPHONE SYSTEMS (SSB/FDM) Companding 115
Look But Don't Touch 53 Frequency Locationsof SCPC Services 116
How ItWorks 54 SCPC ScannerReceiving System 122
Atthe Uplink 57 HeilSC-One SCPC Receiver 127
Atthe Downlink 57 The SCPC System 128
The OtherApproach 59
How To Receive All OfThis 60 CHAPTER 5 PAGE 131
The Ideal SSB Receiver 61 SATELLITE NETWORKS
The HookupOfEquipment History of Data Communications 131
ForTelephone Reception 61 Teleconferencing Via Satellite 131
Connection Problems 65 Digital Radio NetworksVia Satellite 134
What isMultiplexing? 66 DigitalSatellite Network Equipment (ADDS) 135
What Will We Hear? 67 ModulationAssociatesCorporate
Location of Satellite Telephone Systems 67 Data Network 140
Important Points on SSB/FDM 68
iv
Spread-SpectrumTechnology 140 CHAPTER8 PAGE 185
Interactive DataCommunicationsNetwork MISCELLANEOUS SATELLITESERVICES
ServicesbyEquatorial ReutersServices 185
CommunicationsCompany 142 ReutersSmallDishService(SDS) 185
FSKDataonSubcarriers(SbC) 149 ReutersNews-ViewService 186
FSKDataEquipment 149 CommodityCommunicationsNetwork 186
"SunOutage"-TheSatelliteData TheGalaxyDataSystem--
Networks'Problem 152 PresentandFuture 191
FMSquaredTechnology 153 HughesSatelltteSystemDescription 195
NewFMCubedBroadcastService 154 PressServicesViaSatellite 199
DataTransmissionNetwork(DTN) 155 (SCPC/FM/FDM)-
UPINewsServices(RnY) 199
CHAPTER6 PAGE 157 APNewsService 199
TELETEXT BASICS CopyingSatelliteFDMSignals
Videotext:APrimer 157 WithaPersonalComputer 200
TelevisionandVBI 157 CommodityQuotations,Inc. 200
AreYouReadyForTeletext? 158 CommodityWorldNewsNetwork 204
ShortHistoryofTeletext 160 Untted VideoSystems 206
TheSatellite-Delivered Services 162 BonnevilleSatelliteSystems 207
MajorTeletextServices 162 PC-QuoteSystem 207
AvailabilityofDecoders 165 SatelliteBroadcastNetwork(SBN) 207
HereArethe Problems 167 ZephyrWeatherInformationService 208
KeyfaxandOtherTeletextServices 169 SatelliteDataNetwork(SDN) 211
ZenithTeletextService 170 SportstickerService 215
AnotherOverviewofTeletext 174 Bonneville/Apple FinancialService 216
NewDSETeletextDecoderKit 176 Agri-SatAgriculturalService 216
Potpourriof"HiddenSignals" 219
CHAPTER7 PAGE 179
OTHERVBI SERVICES CHAPTER9 PAGE 221
OtherVBI(TxTNBI) Services 179 Ku-BAND AND HIDDENSIGNALS
ProgramInformationNetwork(PIN) 180 BroadcastServicesandKu-Band 221
Dow-JonesNewsService 180 TheFutureofKu-Band 221
APNewsCable 181 EquipmentforKu-Band 230
UniqueSatelliteServices: Genesis,
SSSStockMarketService.BeetsData EARTH STATION GLOSSARY OFTERMS 231
Systems,andBonnevilleDataSystems 181 APPENDIX A-
FutureDomesticSatelliteBelt1995 235
APPENDIX B-
NorthAmericanC-BandSatellite
FrequencylTransponderConversionTable 236
DATA COMMUNICATIONS GLOSSARY 237
v
CHAPTER ONE
UNDERSTANDING THE
SATELLITE SIGNAL
MODERN METHODS OFCOMMUNICATION
Until recently, man has been blind to all but example,conversationsbetweencomputersrelayed
those forms of radio waves known as light and by satellite are always digital,while most TV broad
infrared heat rays.Astechnology has improved,so casts are expressed in analog form. However,the
has our ability to communicate. Morse code rapidly trend is to use digital broadcasts as newer and
evolved to radio, television, and now to satellite higher-quality television is developed and as satel
telecommunicationinlessthan acentury.Thesame litesarepackedwith more sophisticatedelectronics
principlesunderlieallforms ofradiowave communi allowing higher amounts of information to be trans
cations. mitted.
ANALOG AND DIGITAL SIGNALS-CODING THE MODULATION-ADDINGTHE MESSAGE TO
MESSAGE RADIO WAVES
Anymessage,whetheritbetheimageandvoice Analog or digital signals can be added onto
of an entertainerordetailsof stock-markettransac radiowaves byaprocesscalled "modulation."Once
tions, must first be changed into aform that can be themessageismodulatedonto aradiowave (known
relayed by radio waves.Ifan analog coding method as the carrier wave because itcarries the informa
is used, the pattern of a message is mimicked by tion), itcan be relayed from asendingto areceiving
electrical voltages. For example, a voice can be antenna.Radios,televisions,andothercommunica
changedinto ananalog signal byamicrophonethat tionequipmentdemodulatethesignalsthey receive;
createsavoltagedeterminedbythe loudnessofthe i.e.,theyextracttheoriginalmessagefromthecarrier
sound.The louderthesound,thehigherthevoltage. wave See Figure 1.0.
Adigitalcoding method usesthenumbers0and1to
conveyallinformation.Forexample,avoicecouldbe Thesimplestmethodtomodulateacarrierwave
expressedindigitalformiftheloudness ateachpoint istoswitch itonandoff.Forexample, Morse code is
intimewas expressedbynumbers, orpatternsofO's relayed as series of dots and dashesbyturning the
and t's. A photograph can also be described by a carrierwave on and off. The most familiar methods
longseriesof1'sando'sthatarecoded sothatsome of modulationused todayare amplitude modulation
impart information about the location of the dots (AM) and frequency modulation (FM) as encoun
composing the picture and others determine the tered,forexample. inAMand FMradio. Inamplitude
brightness and color of the dots. Computers exclu modulation,the powerof acarrierwave isvaried in
sively use digitallycoded information. accordancewiththemessagebeing relayed,whilein
Uplinks can relay eitherdigitalor analog forms frequency modulation the frequency of the carrier
ofthesame message. Convertersthat cantranslate wave isvaried.
between these two languages are available. For
1
Each type of modulation has advantages satellite as the signal becomes spread out and is
and disadvantages. AM messages must have high absorbed bywatervapor, clouds, and othermateri
powerstotravellong distanceswithoutbeing weak als. This weakening is called "attenuation." Amplifi
ened too severelyfor clearreception. Theyare also cation, the opposite process, increases the signal
more prone to picking up static than are FM mes strength. In the same fashion that a photograph is
sages. Ontheotherhand, FMsignalsneedrelatively enlarged but not changed, amplification retains the
lowerpowerfor successful, long-distancetransmis original message. All televisions, radios, stereos,
sion, but must use a substantially wider range of and othercommunication equipment amplify a sig
frequencies than AM messages would to carry the nal beforetheydemodulate carrierwaves.
same amountofinformation.Satellitemessagesare
frequency modulated for these reasons. As signals NOISE-HINDERING CLEAR COMMUNICATION
cover the long distances between earth-receiving
and-sending stations and satellites, the power be Inaperfectcommunicationsystem,thesignal
comes so low that AM relays would be unusable. would be relayed with no interference or noise.
Also,satellitecommunicationrelaysuseaverybroad However, television or radio broadcasts are occa
range of frequencies as is required by FM broad sionallyofpoorqualityor"noisy." Noiseispresentin
casts. all matterattemperatures above absolutezero, the
temperature at which all molecular motion ceases.
BANDWIDTH-HOWMUCH INFORMATION CAN (There isnotemperaturecolderthan absolutezero).
BE CARRIED? Noise iscaused by the endless motionof the mole
culesthatcomposeallmatter.Thesesmall,vibrating
Justasalarge-diameterpipecancarry more charged particles generate radio waves that mask
waterthanasmallone, asignalcoveringawideband the organized signal sent by man. Noise from the
offrequencies can carry more informationthan can environment becomes strongeras the temperature
one coveringanarrowband.This range offrequen increases. Receivingantennasaswell pick up more
cies of radio waves is termed the "bandwidth.' For ofthis environmental noise asthe signal bandwidth
example, if a television message is relayed in the increases. Furthermore, noise isgeneratedbyinter
frequency range from 54 million cycles persecond nalheatinamplifiers,receivers,andotherelectronic
(abbreviated 54 megahertz) to 58.2 megahertz, it equipment.
wouldhaveabandwidthof4.2megahertz.Eachtype Noise isalways presentin satellitecommu
of communication medium uses a characteristic nication systems (see Figure 1.1). The quality of a
bandwidth. Media such as television require a sub communication is determinedby the ratio of signal
stantiallywiderbandwidththan doradioortelephone to-noise power. For example, ifa signal of 10watts
because much more information is necessary to is received along with 5 watts of noise, the picture
recreate apicturethan to recreate musicor avoice. qualitywill bepoorerthan ifasignal of 10watts was
For example, a TV communication channel of the receivedwith 1wattofnoise. Inthecaseoftelevision,
satellite Galaxy1islocatedbetweenthefrequencies the signal must be at least 63,000timesthe accom
of 3.70 and 3.74 billion cycles per second, abbrevi panying noise inorderfor a"high-quality,"pictureto
ated as gigahertz. This channel therefore has a be received.
bandwidth of 40 megahertz. Voice channels, how
ever normally require a bandwidth of only 3,000 to The basic satellite video signal under the
4,000 cyclespersecondfor qualitysound reproduc NTSC (National Television Standards Committee)
tion. standards for colortelevision uses a channel band
width of 6 MHz to carry all of the necessary picture
AMPLIFICATION-INCREASING THE SIGNAL informationalongwiththe audio section.This 6MHz
STRENGTH signal is spread over a basic 36 MHz bandwidth in
order to reduce the possible terrestrial microwave
Messages beamed into space from an up interference.
link antenna are weakened on their voyage to a
2
AMPlITUDEMODULATION
\ I
I AM 11 _ _I1 AM II
MODULATION DEMODULATION
CIRCUIT +H-t++t-H+f-t-l,..,f-+ CIRCUIT
CARRIERWAVE I \
~ n n ~
U U
~ FREOUENCYMODULATION n ~
FMMODULATEDSIGNAL
\ I
u u U
1- -ttt+t1~H+t-+- 1 1
CARRIERWAVE
FM I - I FM I
MODULATION DEMODULATION
ICIRCUIT CIRCUIT
AUDIOORVIDEOSIGNAL . ORIGINALSIGNAL
\
Figure1.0 Amplitudeand FreqiJencyModulation of Signals. Themodulatedaudio, video,
ordata signalcanbe relayedbycables,over-the-air,orby satellite.
ORIGINALSIGNALWITHOUTNOISE
SIGNAL+NOISEA
NOISEA
Figure1.1 TheEffectofNoise onaRadio or Television Signal. Ifthelevelofnoise
istoohigh, asincase B, thesignalisgarbledoreven unintelligible.
3