CA1324434C - Method and apparatus for jamming selected television programs - Google Patents

Abstract

ABSTRACT
In order to selectively jam M selected channels to selected subscribers in a CATV system, each of M different oscillating signals, each of which oscillating signals has a duration longer than the duration of the horizontal synchronization signal of the television channel it is to jam and a frequency higher than the carrier wave of the channel is is to jam, are in turn added to the television signal circuits of those subscribers who are not authorized to recieve the particular channel being jammed by the jamming signal being added. The television set of the non-authorized subscriber picks up the higher frequency jamming signal as the valid horizontal synchronization signal and therefore ignores the valid horizontal synchronization signal, with the result that the channel in question is unviewable on the the television set of the non-authorized subscriber.

Description

-` 13244~4 ~.
METHOD AND APPARATUS FOR JAMMING SELECTED TELEVISION PROGRAMS : .
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~ackgroun~ of the Invention ~leld of the Inventlon:
The lnvention relates to CATV system~, and more -~
particularly to a method and appara~us ~or selectively ~a~ming ~elec~ed channel~ to ~elected -~ub~crlber~ ln a CATV . -~y-~te~
De~crlption of Related Art: `
CATv sy~ta~ in whl&h there are a number of ~hannel~
provlded to the subscrlber~ are well known. Many CATV . .
~y~tems charge di~erent amounts to their varlous ``
subscrlber~, dependlng on how many o~ the supplled channels `~
the particular subscrlber vants to recelve. For example only, a CATV syste~ ~ay offer channel~ 1 through 12 `~
lnclu~lve. The charye ~or vievlng ~hannels 1 through 9 . ::
lncluslve mlqht be $Y.OQ per month. The charge for viewing ; ~ `-channels 1 through 9 lnclusive plus also channel lo mlgh~ be ~Y.00 ~ $10.00 per ~onth. Tho charge for vlewlng channels 1 ~ `
though 9 lncluslve plus channels 11 and 12 mlght be $Y.00 $20.00 por aonth. Accordlngly, ~lnce all of the ~ub~crlbers `~
.... , .... ;, ..
~re connected to the ~a~e controllod access mediu~ a ~eans ha~ to be found to selectlvoly dony channels 10 and~or 11 and/or 12 to tho~e subscrlbers ~ho have not pald the 25 addltlonal chargota~
It 1~ knovn ln the art that cortaln channels can be ~craoblod prlor to trans~lsslon from the ~uppller's head end --;~
and sub~equently descra~bloa at the home end~ of tho~e ~ub~crlber~ vho have pald for tho~e scrambled channels. A
devlco co~only roferred to as a descrambler ls ln-~talled ln l `
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1 the paying subscriber~ home~, whlch re~tores the scrambled ~ televl~lon ~l~nal. one probl~m wlth such a system 1~ that the descrambler must be lnstalled, thu~ access to the sub~crlber's home and man power 1~ needed. A ~econd problem occurs lf th~ sub~crlber no longer wants the channel~, or aefaults ln paylng for the channels, agaln acce3s to hls home and man po~er 1~ needed to remove the descrambler. A third problem is that if a ~ub~crlber can buy or build an illegal .
descrambler he can obtain the addltlonal channels wlthout paying for them.
The other knovn m~ans o$ selectively denying channels to selective subscribers is by selectively ~amming the channels to be denied to the subscribers who have not paid for them.
one known ~ethod of ~am~lng channels ls to send, along wlth ~ `
the slgnal of each channel to be ~ammed, a Qlqnal having a repetition rate close to the vertlcal syncronizatlon rate and ~`
o a qreater amplitude than the ver~lcal synchronization ~:
~ . ., slgnal. The televlQion vill pick up the ~am~ing slgnal as;~
the synchronlzation signal and wlll therefore produce a v~rtically un~table picture. one problem vith thls means is ~ ;
that a vortically un~tablo plcture 1~ not as unwatchable a~ a horlzontally un~table plcture.
another knovA means of ~a~ming channels is to send, ` .
alon~ vlth the slgnal of oach channol to be ~a~med, a slgnal havlnq a repot~on rate clo~e to tbo horlzontal ~
~ynchronlzatlon ~lgnal and of an amplitude greater than the ~;
horlzontal 3ynchronlzatlon slgnal. ?he televlslon will plck up the ~au~lng sl~nal a~ the synchronlzatlon slqnal and wlll ;~ `
thoreforo produco a horlzontally un~table picture. ~ !'`' ;.
A co~mon problem vlth both of the known methods and ways `~

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'',. "' '.~ '~ :`",' ` 132~434 1 in which t~ey are known to be carried out 1~ that the interfer~ng signal ~ust be produced, and lt must be comblned only with the television channel signal going to the subscrlber~ vho have not pald for that channel. If the interfering signal were comblned wlth the televi~lon slgnal to all ~ub~crlber~ they would all have that channel ~am~ed.
A known means of ~electively combining each of the --different ~amming signals that are being put out for each of -~
the dlfferent channels to be ~ammed with only those televl~lon slgnals golng to the subscrlber~ ~ho are not authorized for that particular channel is used ln us Patent No.4,521,~0g~ The known means used ln US Patent No.4,521,809 regulres one separate llne per subscrlber and one ~wltch per `
~ubscrlber per channel that ~lght be ~a~med. The ~eparate `
sub~crlber lines are each coupled to a dlfferent swltch for ":- ;
each channel that alqht be ~a~med, thereby creating a ~wltch and subacrlber llne ~atrix in which each sub~criber line has a unique ~vltch for each channel that ~lght be ~am~ed, :"~ `-`; u controlllng t~at subscrlber's access to ~ald channel, and in whlch all swltches controlllng subscrlber acce~s to a . . .
partlcular channel are connected to each other. For exa~ple ` `
only, lf the ~ltuatlon ls that channel "A" la to be ~ammed to .~
subscrlber~ 2n~ and ~3n~ each o~ the channel "A"
swltchos that couple the ~am~lng slgnal mean~ to the ;~ -subscrlbor llnes N~ "2" and "3" are clo~ed. Accordlngly, lf there are 1000 ~ubscriber-~ and S channels to be ~ammed, 1000 separate ~ub~crlber llnes are needed, and ~5 x 1000) =
.... .
5000 svltches are roqulred. Accordlngly, a large number o , `
swltches 1~ requlred. Addltlonally, lt would not be an easy ~atter to add further ~ub~criber line~ and ~wltche~ to the , . . . .

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~witch and subscriber line matrix.

SUMMARY OF T~ INV~l!Ln~

The invention teaches a rr~thod for sehctively controllin~ subscriber access to select~d television channels which are bein~ transmitted over a controlled access rnedium each of which television channels has a re~ularly spaced horizontal synchronèation si~nal and each of which television channels is modulated onto separate carrier wavcs, each having a different carrier frequency; said method is characterked in that said rnethod is comprised of the steps of: generatin~ an . . .
oscillatin~ si~nal having a duration longer than the duration of any of the regularly spaced horkontal synchronèation si~nak of any of M television si~nals that are to be sehctively jarnrned; and usin~ M separate frequency ~enerating circuits, each of which generates only one frequency, whieh fre~uency, if coupled with the ~enerated oscilbtin~ si~nal~ ~nll cause the ~enerated oscillating signal to have a frequency hi~her than the unlque carrier wave frequency of the carrier wave of the television channel it is to Jam, yet cbse enou~h to that carrier wave's frcquency to b~ confusin~ with that carrbr wave to a televkhn sT~nal circuit; and In turn, for separate periods of approxlmately 63.5~S/M, couplin~ a dlfferent one of the frequencles from ~he M
separate frequency generatin~ clrcults with the osclllatln~ sl~nal, thereby ~eneratin~
M dtfferent o~cllbtin~ sl~nak {where M Is an inte~er that is equal to the number of controlbbh services Ih. channels) to be jammed}, each of which M different osclllatln~ sl~nals bsts for approxlmately 63.5/uSlM, and each of which M dtfferent " ' ;':

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oscillating signals has a duration longer than the duration of the horizontal synchronization signal of the tele~ision signal said oscillatin~ si~nal will be used to jam, and each of which M different osGillating signals has a frequency higher than the carrier wave of the channel it is to jam, yet close enough to the frcquency of the carrier wave of the channel it is to Jam to be confusin~ with that carrier wave to a television set ~thereby creating M different appropriate jamming signals ~ach of which lasts for approximately 63.5~uS/M); in turn, for separate periods of approximately 63.5/uS/M each, combining a different one of the created M different appropriate jamming si~nals with the television si~nals ~oin~ to all of the subscribers who are not authorked to receive the particular channel bein~ jammed by that particular appropriate jamming signal, until eaeh of the M different appropriate jamming signals has been combined one time with the television si~nals ~oin~ to the appropriate subseribers; and then startin~ the eyelQ over a~ain and eontinuin~ to start the cycle over a~ain each time the cycle ends~
The inventhn, in addition to the stated method, also teaehes an apparatus for seleetively controllin~ subseriber access to seleeted tehvision channels which are bein~ transmitted over a eontrolled aeeess medium eaeh of whieh television ehannek has a re~ubrly spaeed horkontal synchronization si~nal and each of which televisiion channek is modulated onto separate earrier waves, each having a different carrier fre~ueney: saiJ apparatus tau~ht by the invention is charaeterized in that it is eomprised of: ~eneratin~ means for ~eneratin~ an oscillatin~ si~nal havin~ a duration 132~3~
longer than the duration o$ any of the regularly spaced horizontal synchronization signals of any of M television signals; and M sQparate fr~quency ~neratin~ circuits, each of which generates only one frequ~ncy, each of which frequency generatin~
circuits, if coupled with the generating rneans will cause its ~enerated oscillatin~ si~nal to have a frequency higher than the unique carrier wave frequency of the carrier wave of the television channsl it is to jam, yet close enough to that carrier wav~'s fr~quency to be confusing with that carrier wave to a television si~nal circuit; and couplin~
means which, in turn, for separate periods of approximate~ 63.5JuS/M each, couple 8 different one of the M separate frequency generating circuits with the ~enerating rneans, thereby generating M different oscilJatin~ si~nals {where M is an inte~er that is equal to the number of controllable services (ie. channels) to be jammed}, for periods of time that may be as short as 63~5~uS/M, and each of which M different oscillatin~ si~nals has a duration lon~ar than the duration of the horizontal synchroni~ation si~nal of the tele~ ision si~nal said oscillatin~ si~nal will be used to jam, and each of whkh M diffcrent oscillatin~ si~nals has a frequency hi~her than the carrbr wave of the channal it is to hm, yet close enou~h to the frequency of the carriar wa~e of the channel it is to jam to ba confusin~ with that carrier wavc to a tehvision set (thereby creatin~ M different appropriate jammin~ si~nals each of which may last for as littla as approximately 63~5~uS/M); combinin~ means capable of combinin~, for a period of tima as short as 63.5~uS/M, any of the created M different approprbte Jammin~ si~nals with the C `.~

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1 tel~vl~lon ~l~nal~ golng to all of the ~ubscrl~ers vho are not autho~l2ed to reGelve the partlcular channel belng ~ammed by that ~amming slgnal; a service control Inqan~ for :.
instructlng the combining means to combine one of the appropriate ~ammlng signals vltb those subscrlbers' llnes who .. ~ ... ...are not authorized to receive t~e channel which sald -:
approprlate ~a~lng ~lgnal ~ a~, and then after a period of approxl~ately ~3.5uS~M lnstructlng the combining means to . : .
stop comblnlng the said approprlate ~ammlng ~lgnal wlth the subscriber~' llne~ who are not authorized to receive that `. .
particular channel, and then instructs the comblning means to . .:
combine a different appropriate ~amming signal wi~h those subscrlber~' lines vho are not authorlzed to recelve the :
channel which said di~ferent appropriate ~ammlng slgnal wlll ~am, and then after a period of approxlmately 63.5uS/M
in~tructlng the combinlng means to stop combining the said " :.
dlfferent appropriate ~amming slgnal ~ith the subscribers' `~
llnes ~ho are not authorized to receive the channel whlch the ~i `.
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-~ald dlfferent appropriate~ ~amming signal ~ am, and then `: ......... :
continues to in~truct the co~blnlng means to comblne and stop "; . `
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comblning ln turn, for turns of approxlmately 63.5uS~M each, .. ~ . . ..
each of the remalnlng appropriate ~ammlng slgnal~ wlth the . ,~ :. .. .
sub~crlbers' lines ~ho are not authorlzed t`o recelve the ;`~
': .; ~.,i '`,, ",' , , channel vhlch the approprlate ~amming slgnal ln questlon ~ams ;~
... .. ..
untll each appropriate ~ammlng signal has been comblned wlth the ~V ~lqnal~ to the approprlate sub~crlber~ one and only . ``:
one tl~e for perlod~ of time of approximately 63.5uS/M each, ~ r~
and then ~tarts the cycle over agaln, and continues to start ~ . `.
the cycle over agaln each tlme the cycle ends. .
Some of the advantages of the method and apparatus ;~
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~. '",'' '~' ' 6 ~' `--` 132~34 1 taught by the invention are that a very effectlve ~ammlng of each of the channels to be jammed is achleved, and that only one iamming signal s~ltch may be requlred per subscrlber.
Another advantage is that acces~ to the ~ub~crlber'~ home 1 not needed to allow the subscriber to receive channel~ ~hat are ~ammed, and acce3s to the subscrlber's home is not needed to deny the subscriber access to channels that are being ~am~ed~ An~t~r advantage is that additional ~ubscribers can easily be added to the system as each subscrlber need only be ~ `
connected to the system by one ~ub~criber connection and one ~a~ing signal svitch, accordlngly, to add on an ad~itlonal subscrlber all that may be needed i-~ to add on to the end of a llnear ~erles of sub~criber connectlons and ~ammlng ~lgnal :
svitches, one addltional subscriber c~nnection and one ` ;
.:, ~ ,, addltlonal ~a~lng slgnal s~ltch.

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~rlef Description of the Drawings ``;` `
Figure 1 i~ a -~che~atic diagra~ ~howlnq a preforred` ~ ;
e~bodle~ent of an apparatus of the invention; ``~
Flguro la 1~ a sche~atlc diagra~ ~howlng a preferred`:``
o~bodle~ent of an apparatu~ of the lnventlon .i . . .
vorking ln con~unctlon with a control mean~ and TV
~lgnal ~wltche~
Flgure 2 i~ an lllu~tratlon ~howlng the frequency ~pectrum - ` `
of a television slgnal and indlcatlng where the `~; ~`
~aunlng slgnal of the lnventlon would fall wlthln ```
that frequency spectrum;
Flqure 3 ls a tl~lng dlagra~ lllu~tratlng one po3slble tl~lng sche~e for the lnventlon when lt has been ~et up to ~electlvely ~am slx channel~ to selected , s .~''' '' ''`
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subscribers:
Figure 4A is a schematic diagram of the master switch of the praferred embodiment of an apparatus accordin~ to the present invention Fi~ure 4B is a schematie dia~ram showing the equivalent R.F. circuit of the master switGh illustrated in Figure 4A, when that master switeh is on;
Fi51ure 4C is a schematic dia~ram showin~ the equivalent R.F~ circui~ of the master switch illustrated in Figure 4A, when that master switeh is off~

DESCRIPTION OF THE PREFERR~2 EMBODIMENTS
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The prefQrred embodiment of the method for seleetively controllin~
subseriber aeeess to seleeted television ehannels whieh are bein~ transmitted over a eontrolbd aeeess medium each of whieh television channels has a re~ularly spaced hori~ontal synchroni~ation si~nal and aaeh of whieh television ehannels is modulated onto separatQ earrhr waves, eaeh havin~l a different earrier frequeney is comprised of the steps of: qeneratin~ a frequeney modiulated oseillatin~ si~nal havin~ a duration hn~r than the duration of the horkontal synehronization si~nal of any of the television sl~nak said oseilbtin~ si~nal will be used to jam; usin~ M separate frequeney ~neratin~ eireuits, eaeh of whieh ~enerates only one frequeney, whieh frequeney, if eouphdi with the frequeney modulated oseillatin~ si~nal, will eause the frequeney modubted oseillatin~ si~nal to have a frequeney h~her than the unique 1~2~3~
carrier wave frequency of the carriQr Wave Of the television channel it is to Jam, yet close enough to that carrier wave's frequency tO be confusing with that carrier wave to a television signal circuit for M Separate time periods of approximately 63.5~S/M
each {where M is an integer that is equal to the number of controllable services (ie.
channels) to be jammcd} SclcGtivcly coupling the oscillatin~ signal With a differcnt onc of the M different frQquenciQs, each of which frequencies will cause the oscillatin~
si~nal to have a frequency hi~her than thc carriCr wave of thC channel n is to jam, yet ~-close enou~h tO the frcquQncy of the - 8a - , .
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132~34 1 carrler wave of the channel lt is to ~am to be confuslng wlth that carrier wave to a televlslon set, and thereby creatlng M
different appropriate ~amming signals each of which last.~ or approxl~ately ~3.5uS~M; in turn, for separate perlod~ of approximately 63.5uS/M each, combining a dlfferent one of the created M different appropriate ~ammlnq aignals wlth the .;.`
telev~sion signals going to all of the ~ub~criber-~ who are :: . ... . ..
not authorize~ to rece~ve the particular channel being ~ammed .
by that particular appropriate ~amming signal, until each of the M different approprlate ~amming slgnals has been comblned one and only one tlme with the appropriate televlsion signals; and t~en ~tarting the process over agaln and con~lnulng to do so for as .long aa lt waa desired the aystem ~ .
should selectively ~am selected television channels. :` .
The preferred e~bodlement of an apparatus according to .
the lnventlon ls illustrated in flgure 1~ The TV signal 10, .
~hlch ls received by the preferred embodiement carries all of . .
ehe posslble televislon channels the preferred embodlement ls --.:
bullt to ~am, and ~ay al~o carry addltlonal televlslon :. :
channels~ The preferred embodlo~ent ls comprlsed of: a aet ~:
of televlslon ~lgnal splltter clrcults 11; a set of ~amming ;.
~lgnal swltchea 13; a aet of subscrlber slgnal comblner j :
~odules 12; an oaclllator clrcult 17; a coupllng means 18; a channel ele~ent bank 19 made up o a serles of dlfferent ele~ents each of ~hlch when connected to the osclllator clrcult vlll cause lt to put out a ~ammlng slgnal sultable -.
for ~aumlng a dlfferent pre-determlned one of the TV channels `~
ln the TV slgnal 10; a maater awltch 16; a low paRs fllter '''"''""'`''?'`'''''''''~"`''' 15; and a ~ervice control center 14~ . ;.
In t~e preferred embodlement each of the televls~on ;~
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1 slgnal splltter ~lrcult~ 11 receive~ the TV ~lgnal 10. The ~et of ~a~mlng ~l~n~l swltche~ 13 ln the preferred embodiement ls made up of N (where N is an integer) PIN
Dlodes RF switches. Each of the ~ammlng slgnal swltches recelves the ~amming slgnal. The ~et of sub~crlber conn~ction~ in the preferred embodiement ls made up of N
~ . .
slgnal co~b~ner modules. In the preferred embodlement the ~lgnal comblnar modules are con3tructed uslng splltter clrcult-~ Each ~ubscrlber connection connects the slgnal beinq put out from that sub~crlber's televlsion slgnal splitter c~rcult and the signal being put out by that subscrlber's ~amming slgnal svitch. Accordingly, when the subscriber' ~amming signal s~ltch ls closed whichever channel ls bein~ ~a~med by the ~amming slgnal will be ~ammed `~
on that ~ubscrlber's television set.
In the preferred e~bodlemant the osclllator clrcult ls con~tructed uslng an LC tlnductor-capacitor~ circuit and the neces~ary components to produce a frequency modulated "``
osclllatlng freguency. The osclllator clrcuit 17 puts out a ``
~urst of radlo-freguency slgnals Ylth a duratlon equal to ``
the {~tiae for a full horlzontal llne scan of one of the channels beln~ recelved b~ the subscrlbers) ~ M) {where M is ` `;"~
an lnteger that is equal to the nu~ber of controllable ~ "
servlces (l.e. channels) to be ~ammed). Accordlngly, since the tlme to ~can a normal horizontal llne ls approximately `
~3.5uS, lt ls not recommended that the system be set up to ~a~ more than a naxl~um of 8 channels. : -~ach of the elements ln the channel element bank 19 of tho preferred embodlement 1~ an LC ~inductor-capacltor) ~ -clrcult. The lnductor and capacltor oÇ each element ln the ,'"~""'"''.

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channel element bank is selected so that when that ~l~m~nt is coupled to th~ oscillator circuit the oscillator circuit will put out a frequency modulated jamming si~nal at a frequency hi~her than the carrier frequency of the TV si~nal that ~lement was install~d to jam.
The couplintl rneans 18 of the preferred embodiment is a combination of switchin~ PIN diodes. The couplin~ means 18 is able to couplQ any one of the elements in the channel elernent bank ~th the oscillator circuit for a period of time at least as short as 63.5~S/M.
Figure 4A is a schematic diagram of the master switch 16 of the pre~erred embodiment, which illustrates the construction of the master switch 16.
The master switch 16 is a PIN diodes RF interruptor that has a controlled rise and fall time tO minimize the ~eneration of spurious products durin~ switchin~. The master switch is rnade up of the followin~ components: a ~rounded capacitor connected with an inductor (which is called an ~RF Choke~); six additional capacitors; five diodes; and four additional inductors. A first capacitor, which is the input, is followed by a shunt RF Choke, followed by a series first dlode, followed by a shunt second capacitor, ` "
folhwed by a serhs second diode, followed by a series first inductor, followcd by a shunt third capacitor, followed by a serhs third diode, followed by a series second inductor, followed by a shunt fourth capacitor, followed by a series fourth diode, followed by a series third inductor, followed by a shunt fifth capacitor, followed by a series fifth diode, followed by a shunt fourth inductor, followed by a series sixth capacitor, which is the output. When the rnaster switch is on, direct current flows throu~h the diodes and they become conductive; the master switch is then the - 1 1 - ' ~ 132~3~
equivalent of a low pass filter having a cut-off frequency higher than the hi~hest frequency of interest, the schematic diagram of that equivalent cirCuit is illustratcd in Figure 4B. When the master switch is off the current stops flowing through PIN
diodes and then each diodc becomes likc a small capacitor; the master Switch is thcn the equivalent of a capacitive ladder attenuator, which equi~alent circuit is illustrated in Fi~ure 4C.
The low pasS fllter 15 of the preferred embodiment is made up of capacitors and inductors. The purpose of the filtcr is to climinate the harmonics from thc oscillator and rnaster sw`ltch circuit~
The service control center 14 is an ebctronic control - 1la~
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1 unit. The ~erviCe control center of the preferred embodlement 1~ ma~e up of a ~lcrocontroller wlth a RO~
program, RAM circults, logic I.C.'5, opera~ional amplifler~
and the neces~ary assorte~ input~, outputs ~nd ~tandard circuitry necessary for operation. The servlce control center, when lt first start~ operatlng inltlalize~ the sy~tem by openlng the ma~ter ~ltch and openlng all swltche~ in the set o~ ~ammlng slgnal swltches and causlng ~he coupllng means to dlsconnect the osclllator clrcul~ from any of the elements .`.
ln the channel ele~ent bank. The 3ervice ~on~rol center then "
causes the coupling means 18 to couple the first element in the channel ele~ent bank with the oscillator clrcult ~or approximately 63.5uS~M (period 1). The servlce control center then, in period 1, causes the svitches ln the set of ~a~ing ~ignal s~itches, ~hich connect to subscribers wbo are ~ `~
not authorlzed to receive the channel vhich wlll be ~am~ed by the ~aaulng slqnal created when the first element in the ;~ "
channel element bank ls coupled wlth the osclllator clrcult to be closed for approximately 6~5uS~M. The servlce control ceneer then, in period 1, causes the master swltch to close C ~or approxlmately 63.5uS~. The service control center then at the end of period ~ cause~ the ~a~te~ swltch to open. The ~`
servlco control center then causes the coupling means 1~ to `-couple thc second ele~en~ ln the channel element bank with the osclllaeor circult for approximately 63.5uS/M (period 2~.
The ~orvlce control center then, ln perlod 2, causes the ~wltches, ln the set of ~a~ming slqnal swltches, which ~ -`connect to subscrlbers vho are not authorlzed to recelve the channel ~hlch vill be ~ammed by the ~ammlng signal created ;
~hen the second element ln the channel element bank ls `~- , ,'.; .
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l coupled with the oscillator clrcult, to be clo-~ed for approximately 63 . 5uS/M. The servlce control center then, in per~od 2, causes the master switch to close for approximately ~3.5uS/M. The ~ervlce control center then at the end of perlod 2 causes the ma~ter ~witch to open. The ~ervlce ~ - `
control center then in dlfferent periods of 63.5uS~M each ~;
contlnues to perform the sald serie~ of operations, u~ing the next element of the channel ele~ent bank in each perlod o~" `" -`
63~5uS/M until each of the element~ in the channel element``
banX ha~ b~en couple~ one and only one tl~e wlth the o~clllator circuit. The ~ervlce control center then starts the ~ald cycle over again, and contlnue~ to ~tart the cycle ` `?"`~
over agaln each ti~e the cycle end~
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~lgure 2 lllu~trate~ a typlcal televl~lon ~lgnal ` ` ;~
frequency spectru~, and vhere the ~amming slgnal of the ;~
inventlon would appear~ The ~au~lng signal of the invention ha~ an`amplltude greater than that of the horizontal ~ynchronlzatlon ~ignal and ls frequency modulated ~o that the `~
f~equency of the ~a~mlng slgnal ls not con~tant~ The ~amming ~lgnal ls thereforc ~ovlng ln the televlslon channel'~ ~
allocatod band to a~sure a ~au~lng that l~ ~ore rellable.`~ :
Tho televl~lon set~ of th~ sub~crlber~ who have had a:~
~a~alng ~lgnal added to thelr ~elevl~lon slgnals, lf tuned to the ~auaed channel, vill therefore lock onto the ~ammlng ~lgnal (slnce lt ls of a greater amplltude) lnstead of the propor horlzontal synchronlzatlon slgnal. Accordlngly, ~ald ``-~ubscrlbers' ~a~ ed channel vlll have a televl~lon plcture that rolls and dlstort~, and wlll have lmpalred ~ound o~ the tel~vlslon progra~. ( ; `
In the preferred embodlement a very effectlve ~ammlng of ~ ;. ; ,. . .

.:, '.. ...
~ . .:
- :

- 132~34 l each of the Ghannel~ to be ~ammed l~ achleve~, and only one ~ammlng ~l~nal swltch 1~ requlred per ~ub-~crlber. Addltlonal advantages to the preferred embodlement are also apparent.
Acce~s to the sub~crlber 's home l~ not needed to allow the sub~crlber to recelv~ ch~nnel~ that are ~ammed, and acceYs to the subscrlber's home ls not needed to deny the sub~criber --access to channel~ ~hat are ~elng ~ammed. Sub_crlber~ can ea~lly be added to the system as each subscrlber need only be `
:- . ,, connected to the sy3tem by one subscrlber connectlon and one ~ammlng slgnal ~vitch, accordingly, to add on an additional -~
..,, ...- .
subscriber all that ls be needed is to add on to the end of the l~near series of subscrlber connections and ~ammlng slgnal swltches, one additional subscrlber connectlon and one `~ - `
; ~; , . .
additional ~a~ming signal s~itch. `"
lS It ls antlcipated that generally the invention and ~ ~ `
. ,. ~ .
e~pecially ~he preferred embodiement of an apparatus of the - .
. , . . ~ .
inventlon vill be used in con~unction with a control means -` `and vith TV signal s~itche~ instead of televl~ion slgnal ~`
splitter clrcuits~ Figure lA illustrates thé invention ~
vor~lng ln con~unction vlth a control means 9 and wlth TV ~`~ -`-slgnal sYitches 20~ In operatlon the TV signal lO al_o ha~
sent along wlth lt coded information that tells the control ~oans 9 vhich TV slgnal svitchos 20 should be turned on, and whlch subscribors should havo which of their channels ~ammed.
~he construction of a control means able to recelve coded . . - .
infor~atlon telling it whlch TV signal swltches to turn on, -;
and vhich sub crlbers should have whlch of thoir channels ~a~med, and able to turn on the approprlate TV Rlgnal swltches and able to lnform the Service Control Center whlch ~,~
subscrlber~ should have whlch of thelr channels ~ammed, is 14 ~ -`-` 132~3~
1 ~ell known by those skllled in the art. The TV slgnal swltches would also be well known to those skllled ln the art and could, for example only, be PIN Dlodes RF swltches or RF
relay ~witches.
When the preferred embodiement of an apparatu~ o~ the lnventlon 1~ u~ed in con~unction wlth a control mean~ and wlth T~ slgnal s~ltche~ it is very slmple for a CATV operator to deny certaln channels to ~ertain subscribers ~rom the head end. The CATV operator merely enters the appropriate lnformatlon lnto the system at the head end. The lnformatlon ls then tran~mltted along ~lth the TV signal to the control ~eans, vhlch decodes that information and provides it to the i~ervice control center. The ~ervice control center then``
causes the appropriate subscrlbers' ~ammlnq signal swltches to clo~e at the appropriate tl~es and the appropriate ~amming ~ ;
slqna1~ arc comblned to tho~e subscrlbers received televlsion `~
slgnals, thus dénying them the approprlate cbannel~
Yarlatlon~ to the preferred embodle~ent can easlly be ~ade. The Qiqna1 comblner ~odu1eq could be constructed uslng diroctlonal coupleri~ lnstead of ~plltter circults as ls used ~-ln the preferred embodlement. The swltches of the set ofi `
~a~mlng ~lgnal svltchei3, could for example only, be RF Ga As ```~
Fet svltches lnstead of PIN Dlodes RF swltches as are used ln tho proferred e~bodle~ent. ~he ~a~ter swltch, for example ~-~5 only, ln~tead of belng con~tructed as de~crlbed for the` "i preferred e~bodlement, could be constructed uslng a Ga As Fet RF a~ltch a~e~bly. - -Addltlonal varlatlon~ to the preferred embodlement are al~o po~slb1e, the follovlnq are only a few addltlonal ',~
examp1es. The osci11ator clrcuit, coupllng means and channel . - .. . ... .

. ., ~. .

: 1324~3~

element bank could be replaced by using M independent osciUator circuits, each putting out a diffe~ent janming signal. lhe LC elements of the preferred embodiment oould be replaced with quartz crystals, or with a ceramic resonator, or a saw Iesonator.
S Finally, many alternative ways to construct the service control center and some of its componenes wiU be clear to those skiUed in the art.
Accordingly, many alternatives to the construction of the preferred embodimene, some of which are obvious to those sldUed in the art but not specificaUy stated herein, wiU be apparent to those slcilled in ehe art. This disclosure is ~ore t~ be understood as illustrative of ~e invention and not as a limitation o~the in~ention. All such modifications and alternatives which do not de~t ~onn the teacl~ngs of this invention are intended eo be included within the ' " ' .

'," ` ' , `' " ' -~t ' -:.:
,.",.

~ .

Claims (13)

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE PROPERTY OR
PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:

1. A method of selectively preventing the viewability by multiple unauthorized subscribers, and allowing the viewability by multiple authorized subscribers, of, where M is an integer, from 1 to M selected television channels, each of which M selected television channels is respectively referred to as channel 1, channel 2, ... channel M, and each of which M selected television channels is referred to in general as channel Z, where Z represents a number from 1 to M, wherein channel Z has a television signal and a unique carrier wave which has a unique carrier wave frequency, and wherein said television signal has a regularly spaced horizontal synchronization signal and is modulated onto said unique carrier wave, accordingly there are M television signals and M unique carrier waves, and wherein said multiple authorized and multiple unauthorized subscribers are each using a television signal circuit to receive the M television signals of the M selected television channels, which television signals are being transmitted over a controlled access medium to eachsubscriber's television signal circuit, and accordingly are being transmitted to multiple television signal circuits, wherein said method is characterized in that it is comprised of the steps of:

(i) generating an oscillating signal having a duration longer than the duration of any of the regularly spaced horizontal synchronization signals of any of the M television signal;
(ii) using M separate frequency generating circuits, each of which generates only one frequency, to generate M
frequencies, each of which frequencies is respectively referred to as frequency 1, frequency 2, ... frequency M, and each of which frequencies is referred to in general as frequency Z, wherein each frequency generating circuit generates a frequency Z, which if coupled with the generated oscillating signal, will cause the generated oscillating signal to have a frequency higher than the unique carrier wave frequency of the carrier wave of channel Z, yet close enough to that carrier wave frequency to be confusing with that carrier wave to a television signal circuit;
(iii) in turn, for separate periods of approximately 63.5µS/M
each, wherein Z in turn is each of the numbers 1 to M, coupling the frequency generating circuit that generates frequency Z with the generated oscillating signal, thereby creating M different jamming signals, each of which is respectively referred to as jamming signal 1, jamming signal 2, ... jamming signal M, and each of which is referred to in general as jamming signal Z; and (iv) starting a cycle and going through a cycle, which cycle consists of, in turn, for separate periods of approximately 63.5µS/M each, where Z in turn is each of the numbers 1 to M, combining jamming signal Z with the television signal of channel Z that is going to the television signal circuits of the multiple unauthorized subscribers who are not authorized to view channel Z; and at the end of each cycle, again starting and going through the cycle.

2. A method of selectively preventing the viewability by multiple unauthorized subscribers, and allowing the viewability by multiple authorized subscribers, of, where M is an integer, from 1 to M selected television channels, each of which M selected television channels is respectively referred to as channel 1, channel 2, ... channel M, and each of which M selected television channels is referred to in general as channel Z, where Z represents a number form 1 to M, wherein channel Z has a television signal and a unique carrier wave which has a unique carrier wave frequency, and wherein said television signal has a regularly spaced horizontal synchronization signal and is modulated onto said unique carrier wave, accordingly there are M television signals and M unique carrier waves, and wherein said multiple authorized and multiple unauthorized subscribers are each using a television signal circuit to receive the M television signals of the M selected television channels, which television signals are being transmitted over a controlled access medium to each subscriber's television signal circuit, and accordingly are being transmitted to multiple television signal circuits, as claimed in claim 1; which method is further characterized by using M frequency generating circuits each of which generates a frequency which is also frequency modulated.

3. An apparatus for selectively preventing the viewability by multiple unauthorized subscribers, and allowing the viewability by multiple authorized subscribers, of, where M is an integer, from 1 to M selected television channels, each of which M selected television channels is respectively referred to as channel 1, channel 2, ... channel M, and each of which M selected television channels is referred to in general as channel Z, where Z represents a number from 1 to M, wherein channel Z has a television signal and a unique carrier wave which has a unique carrier wave frequency, and wherein said television signal has a regularly spaced horizontal synchronization signal and is modulated onto said unique carrier wave, accordingly there are M television signals and M unique carrier waves, and wherein said multiple authorized and multiple unauthorized subscribers are each using a television signal circuit to receive the M television signals of the M selected television channels, which television signals are being transmitted over a controlled access medium to each subscriber's television signal circuit, and accordingly arc being transmitted to multiple television signal circuits, which apparatus is comprised of:

(i) generating means for generating an oscillating signal having a duration longer than the duration of any of the regularly spaced horizontal synchronization signals of any of the M
television signals:
(ii) M separate frequency generating circuits, each of which generates only one frequency, and each of which is referred to in general as frequency generating circuit Z, wherein frequency generating circuit Z is designed to generate a frequency that, when coupled with the generating means, causes the generating means to generate an oscillating signal having a duration longer than the duration of the regularly spaced horizontal synchronization signal of channel Z and a frequency higher than the unique carrier wave frequency of the carrier wave of channel Z, yet close enough to that carrier wave frequency to be confusing with that carrier wave to a television signal circuit;

(iii) a coupling means which is able to couple any of the M
separate frequency generating circuits with the generating means for a period of time at least as short as 63.5uS/M, thereby causing the generating means to generate a jamming signal which is referred to in general as Jamming signal Z;

(iv) a combining means which receives jamming signal Z from the generating means and is able to combine jamming signal Z, for a period of time as little as approximately 63.5µS/M, with the television signals going to the television signal circuits of the multiple unauthorized subscribers who are not authorized to view channel Z; and (v) a service control means for starting and going through a cycle, which cycle consists of instructing the coupling means to couple, in turn, each of the M separate frequency generating circuits with the generating means for separate periods of approximately 63.5µS/M each, thereby, in turn, for M periods of approximately 63.5µS/M each, producing a different jamming signal Z, and in turn instructing the combining means to combine jamming signal Z with the television signals that are going to the television signal circuits of the multiple unauthorized subscribers who are not authorized to view channel Z, until each jamming signal Z has been combined one time with the television signal circuits of the multiple unauthorized subscribers who are not authorized to view channel Z, at which time the cycle ends, and continuing to start and go through the cycle every time the cycle ends.

4. An apparatus for selectively preventing the viewability by multiple unauthorized subscribers, and allowing the viewability by multiple authorized subscribers, of, where M is an integer, from l to M selected television channels, each of which M selected television channels is respectively referred to as channel 1, channel 2,... channel M, and each of which M selected television channels is referred to in general as channel Z, where Z represents a number from 1 to M, wherein channel Z has a television signal and a unique carrier wave which has a unique carrier wave frequency, and wherein said television signal has a regularly spaced horizontal synchronization signal and is modulated onto said unique carrier wave, accordingly there are M television signals and M unique carrier waves, and wherein said multiple authorized and multiple unauthorized subscribers are each using a television signal circuit to receive the M television signals of the M selected television channels, which television signals are being transmitted over a controlled access medium to eachsubscriber's television signal circuit, and accordingly are being transmitted to multiple television signal circuits, as claimed in claim 3; and in which each of the M separate frequency generating circuits, generates a frequency which is also frequency modulated.

5. An apparatus for selectively preventing the viewability by multiple unauthorized subscribers, and allowing the viewability by multiple authorized subscribers, of, where M is an integer, from 1 to M selected television channels, each of which M selected television channels is respectively referred to as channel 1, channel 2,...channel M, and each of which M selected television channels is referred to in general as channel Z, where Z represents a number from 1 to M, wherein channel Z has a television signal and a unique carrier wave which has a unique carrier wave frequency, and wherein said television signal has a regularly spaced horizontal synchronization signal and is modulated onto said unique carrier wave, accordingly there are M television signals and M unique carrier waves, and wherein said multiple authorized and multiple unauthorized subscribers are each using a television signal circuit to receive the M television signals of the M selected television channels, which television signals are being transmitted over a controlled access medium to eachsubscriber's television signal circuit, and accordingly are being transmitted to multiple television signal circuits, which apparatus is comprised of:
(l) an oscillator circuit that generates a frequency modulated oscillating frequency the duration of which may be as little as 63.5µS/M;

(ii) a channel element bank made up of a series of M different frequency generating elements each of which is respectively referred to as element 1, element 2, ... element M, and each of which is referred to in general as element Z, wherein element Z, when connected to the oscillator circuit, will cause the oscillator circuit to generate a frequency higher than the unique carrier wave frequency of the carrier wave of channel Z, yet close enough to that carrier wave frequency to be confusing with that carrier wave to a television signal circuit;

(iii) a coupling means which is able to couple element Z with the oscillator circuit for a period of time at least as short as 63.5µS/IM, thereby creating a jamming signal, and thereby having the capacity to, one at a time, create M different jamming signals, each of which is respectively referred to as jamming signal 1, jamming signal 2, ... jamming signal M, and each of which is referred to in general as jamming signal Z;

(iv) a master switch, that is an RF interrupter that has a controlled rise and fall time to minimize the generation of spurious products during switching, which master switch receives jamming signal Z;

(v) a low pass filter that eliminates harmonics, which receives jamming signal Z from the master switch and which eliminates the harmonics in jamming signal Z;

(vi) a set of jamming switches each of which is able to open and close in as little as approximately 63.5µS/M, and each of which receives jamming signal Z from the low pass filter;

(vii) a set of subscriber combiner modules each of which couples a different pre-determined one of the jamming signal switches with a pre-determined television signal circuit and each of which can couple and uncouple a jamming signal switch with a television signal circuit in as little as 63.5µ/M; and (viii) a service control center that starts a cycle and goes through a cycle, which cycle consists of instructing, in turn, for separate periods of approximately 63.5µS/M each, where Z, in turn, is each of the numbers 1 to M: the coupling means to couple element Z with the oscillator circuit, and the jamming switches that are coupled to the subscriber combiner modules which are coupled to the television signal circuits of the multiple unauthorized subscribers who are not authorized to view channel Z to close, and the jamming switches that are coupled to the subscriber combiner modules which are coupled with the television signal circuits of the multiple authorized subscribers who are authorized to view channel Z to open, and the master switch to close at the start of each of the periods of approximately 63.5µS/M and to open immediately after the end of each of the periods of approximately 63.5µS/M; and continues to start and go through the cycle every time the cycle ends.

6. An apparatus for selectively preventing the viewability by multiple unauthorized subscribers, and allowing the viewability by multiple authorized subscribers, of, where M is an integer, from 1 to M selected television channels, each of which M selected television channels is respectively referred to as channel 1, channel 2, ... channel M, and each of which M selected television channels Is referred to in general as channel Z, where Z represents a number from 1 to M, wherein channel Z has television signal and a unique carrier wave which has a unique carrier wave frequency, and wherein said television signal has a regularly spaced horizontal synchronization signal and is modulated onto said unique carrier wave, accordingly there are M television signals and M unique carrier waves, and wherein said multiple authorized and multiple unauthorized subscribers are each using a television signal circuit to receive the M television signals of the M selected television channels, which television signals are being transmitted over a controlled access medium to each subscriber's television signal circuit, and accordingly are being transmitted to multiple television signal circuits, as claimed in claim 5; and in which said jamming switches are made up of PIN diode RF switches.

7. An apparatus for selectively preventing the viewability by multiple unauthorized subscribers, and allowing the viewability by multiple authorized subscribers, of, where M is an integer, from t to M selected television channels, each of which M selected television channels is is respectively referred to as channel 1, channel 2, ... channel M, and each of which M selected television channels is referred to in general as channel Z, where Z represents a number from 1 to M, wherein channel Z has a television signals and a unique carrier wave which has a unique carrier wave frequency, and wherein said television signal has a regularly spaced horizontal synchronization signal and is modulated onto said unique carrier wave, accordingly there are M television signals and M unique carrier waves, and wherein said multiple authorized and multiple unauthorized subscribers are each using a television signal circuit to receive the M television signals of the M selected television channels, which television signals are being transmitted over a controlled access medium to each subscriber's television signal circuit, and accordingly are being transmitted to multiple television signal circuits, as claimed in claim 5; and in which said oscillator circuit is an LC circuit that produces a frequency modulated oscillating frequency.

8. An apparatus for selectively preventing the viewability by multiple unauthorized subscribers, and allowing the viewability by multiple authorized subscribers, of, where M is an integer, from 1 to M selected television channels, each of which M selected television channels is respectively referred to as channel 1, channel 2, ... channel M, and each of which M selected television channels is referred to in general as channel Z, where Z represents a number from 1 to M, wherein channel Z has a television signal and a unique carrier wave which has a unique carrier wave frequency, and wherein said television signal has a regularly spaced horizontal synchronization signal and is modulated onto said unique carrier wave, accordingly there are M television signal and M unique carrier waves, and wherein said multiple authorized and multiple unauthorized subscribers are each using a television signal circuit to receive the M television signals of the M selected television channels, which television signals are being transmitted over a controlled access medium to each subscriber's television signal circuit, and accordingly are being transmitted to multiple television signal circuits, as claimed in claim 5; and in which said elements of the channel element bank are LC circuits.

9. An apparatus for selectively preventing the viewability by multiple unauthorized subscribers, and allowing the viewability by multiple authorized subscribers, of, where M is an integer, from 1 to M selected television channels, each of which M selected television channels is respectively referred to as channel 1, channel 2, ... channel M, and each of which M selected television channels is referred to in general as channel Z, where Z represents a number from 1 to M, wherein channel Z has a television signal and a unique carrier wave which has a unique carrier wave frequency, and wherein said television signal has a regularly spaced horizontal synchronization signal and is modulated onto said unique carrier wave, accordingly there are M television signals and M unique carrier waves, and wherein said multiple authorized and multiple unauthorized subscribers are each using a television signal circuit to receive the M television signals of the M selected television channels, which television signals are being transmitted over a controlled access medium to each subscriber's television signal circuit, and accordingly are being transmitted to multiple television signal circuits, as claim in claim 5; and in which said coupling means is a combination of switching PIN diodes.

10. An apparatus for selectively preventing the viewability by multiple unauthorized subscribers, and allowing the viewability by multiple authorized subscribers, of, where M is an integer, from 1 to M selected television channels, each of which M selected television channels is respectively referred to as channel 1, channel 2, ... channel M, and each of which M selected television channels is referred to in general as channel Z, where Z represents a number from 1 to M, wherein channel Z has a television signal and a unique carrier wave which has a unique carrier wave frequency, and wherein said television signal has a regualrly spaced horizontal synchronization signal and is modulated onto said unique carrier wave, accordingly there are M television signals and M unique carrier waves, and wherein said multiple authorized and multiple unauthorized subscribers are each using a television signal circuit to receive the M television signals of the M selected television channels, which television signals area being transmitted over a controlled access medium to each subscriber's television signal circuit, and accordingly are being transmitted to multiple television signal circuits, as claimed in claim 5; and in which said master switch is a PIN diode RF interrupter that has a controlled rise and fall time to minimize the generation of spurious products during switching.

11. An apparatus for selectively preventing the viewability by multiple unauthorized subscribers, and allowing the viewability by multiple authorized subscribers, of, where M is an integer, from 1 to M selected television channels, each of which M selected television channels is respectively referred to as channel 1, channel 2, ... channel M, and each of which M selected television channels is referred to in general as channel Z, where Z represents a number from 1 to M, wherein channel Z has a television signal and a unique carrier wave which has a unique carrier wave frequency, and wherein said television signal has a regularly spaced horizontal synchronization signal and is modulated onto siad unique carrier wave, accordingly there are M television signals and M unique carrier waves, and wherein said multiple authorized and multiple unauthorized subscribers are each using a television signal circuit to receive the M television signals of the M selected television channels, which television signals are being transmitted over a controlled access medium to each subscriber's television signal circuit, and accordingly are being transmitted to multiple television signal circuits, as claimed in claim 5; and in which said low pass filter is made up of capacitors and inductors.

12. An apparatus for selectively preventing the viewability by multiply unauthorized subscribers, and allowing the viewability by multiple authorized subscribers, of, where M is an integer, from 1 to M selected television channels, each of which M selected television channels is respectively referred to as channel l, channel 2, ... channel M, and each of which M selected television channels is referred to in general as channel Z, where Z represents a number from 1 to M, wherein channel Z has a television signal and a unique carrier wave which has a unique carrier wave frequency, and wherein said television signal has a regularly spaced horizontal synchronization signal and is modulated onto said unique carrier wave, accordingly there are M television signals and M unique carrier waves, and wherein said multiple authorized and multiple unauthorized subscribers are each using a television signal circuit to receive the M television signals of the M selected television channels, which television signals are being transmitted over a controlled access medium to each subscriber's television signal circuit, and accordingly are being transmitted to multiple television signal circuits, as claimed in claim 5; and (i) in which said oscillator circuit is an LC circuit that produces a frequency modulated oscillating frequency;

(ii) in which said elements of the channel element bank are LC
circuits;

(iii) in which said jamming switches are made up of PIN diode RF switches;

(iv) in which said coupling means is a combination of switching PIN diodes;

(v) in which said master switch is a PIN diode RF interrupter that has a controlled rise and fall time to minimize the generation of spurious products during switching comprised of a grounded capacitor connected with an inductor (which is called an "RF Choke"); six additional capacitors; five pin diodes; and four additional inductors, wherein a first capacitor, which is the input, is followed by a shunt RF
Choke, followed by a series first pin diode, followed by a shunt second capacitor, followed by a series second pin diode, followed by a series first inductor, followed by a shunt third capacitor, followed by a series third pin diode, followed by a series second inductor, followed by a shunt fourth capacitor, followed by a series fourth pin diode, followed by a series third inductor, followed by a shunt fifth capacitor, followed by a series fifth pin diode, followed by shunt fourth inductor, followed by a series sixth capacitor, which is the output, and (iv) in which said low pass filter is made up of capacitors and inductors.

13. An apparatus for selectively preventing the viewability by multiple unauthorized subscribers, and allowing the viewability by multiple authorized subscribers, of, where M is an integer, from 1 to M selected television channels, each of which M selected television channels is respectively referred to as channel 1, channel 2, ... channel M, and each of which M selected television channels is referred to in general as channel Z, where Z represents a number from 1 to M, wherein channel Z has a television signal and a unique carrier wave which has a unique carrier wave frequency, and wherein said television signal has a regularly spaced horizontal synchronization signal and is modulated onto siad unique carrier wave, accordingly there are M television signals and M unique carrier waves, and wherein said multiple authorized and multiple unauthorized subscribers are each using a television signal circuit to receive the M television signals of the M selected television channels, which television signals are being transmitted over a controlled access medium to eachsubscriber's television signal circuit, and accordingly are being transmitted to multiple television signal circuits, as claimed in claim 5; and in which said master switch is a PIN diode RF interrupter that has a controlled rise and fall time to minimize the generation of spurious products during switching, comprised of a grounded capacitor connected with an inductor (which is called an "RF Choke"); six additional capacitors;
five pin diodes; and four additional inductors, wherein a first capacitor, which is the input, is followed by a shunt RF Choke, followed by a series first pin diode, followed by a shunt second capacitor, followed by a series second pin diode, followed by a series first inductor, followed by a shunt third capacitor, followed by a series third pin diode, followed by a series second inductor, followed by a shunt fourth capacitor, followed by a series fourth pin diode, followed by a series third inductor, followed by a shunt fifth capacitor, followed by a series fifth pin diode, followed by a shunt fourth inductor, followed by a series sixth capacitor, which is the output.