It said all TV (regardless mono or colour, analogue or digital) suppliers 
must pay the TV license fee to Thomsons SA & RCA for each unit on sale due 
to the fact that TV was invented by them and they own the patent.  Can 
anyone know the detail about it.  I am wondering the patent should expire 
already since TV was invented for many years.  Any senior one can share the 
knowledge about it!

Thanks,

Scott

In article ,
Scott  wrote:
>It said all TV (regardless mono or colour, analogue or digital) 
>suppliers [...]

What said that?

RCA was involved in TV patent disputes in the 1930s.  It lost.

-- Richard
-- 
In the selection of the two characters immediately succeeding the numeral 9,
consideration shall be given to their replacement by the graphics 10 and 11 to
facilitate the adoption of the code in the sterling monetary area. (X3.4-1963)

"Scott"  wrote in message 
news:6anfr5F38ssn0U1@mid.individual.net...
> It said all TV (regardless mono or colour, analogue or digital) suppliers 
> must pay the TV license fee to Thomsons SA & RCA for each unit on sale due 
> to the fact that TV was invented by them and they own the patent.  Can 
> anyone know the detail about it.  I am wondering the patent should expire 
> already since TV was invented for many years.  Any senior one can share 
> the knowledge about it!
>
> Thanks,
>
> Scott

Electronic TV was invented by EMI* in the mid 1930's and started public 
broadcasting in 1936.

The signal system for analog TV is based on this, but obviously the original 
patents would have run out over fifty years ago!

UK patents max 20 years, US 16 years IIRC.


* Electric and Musical Industries Ltd - registered in England no.53317.

In article ,
   R. Mark Clayton  wrote:

> "Scott"  wrote in message 
> news:6anfr5F38ssn0U1@mid.individual.net...
> > It said all TV (regardless mono or colour, analogue or digital)
> > suppliers must pay the TV license fee to Thomsons SA & RCA for each
> > unit on sale due to the fact that TV was invented by them and they own
> > the patent.  Can anyone know the detail about it.  I am wondering the
> > patent should expire already since TV was invented for many years. 
> > Any senior one can share the knowledge about it!
> >
> > Thanks,
> >
> > Scott

> Electronic TV was invented by EMI* in the mid 1930's and started public 
> broadcasting in 1936.

> The signal system for analog TV is based on this, but obviously the
> original patents would have run out over fifty years ago!

> UK patents max 20 years, US 16 years IIRC.


> * Electric and Musical Industries Ltd - registered in England no.53317. 

Thompson own the patent for SECAM which might still be in force since it
dates from 1965/6.

-- 
From KT24 - in "Leafy Surrey"

Using a RISC OS computer running v5.11

Charles,

Thanks!  Is SECAM used in France or they are running special system that has 
very long valid date?

Regards,

Scott

"charles"  ¦b¶l¥ó 
news:4faa40809acharles@charleshope.demon.co.uk ¤¤¼¶¼g...
> In article ,
>   R. Mark Clayton  wrote:
>
>> "Scott"  wrote in message
>> news:6anfr5F38ssn0U1@mid.individual.net...
>> > It said all TV (regardless mono or colour, analogue or digital)
>> > suppliers must pay the TV license fee to Thomsons SA & RCA for each
>> > unit on sale due to the fact that TV was invented by them and they own
>> > the patent.  Can anyone know the detail about it.  I am wondering the
>> > patent should expire already since TV was invented for many years.
>> > Any senior one can share the knowledge about it!
>> >
>> > Thanks,
>> >
>> > Scott
>
>> Electronic TV was invented by EMI* in the mid 1930's and started public
>> broadcasting in 1936.
>
>> The signal system for analog TV is based on this, but obviously the
>> original patents would have run out over fifty years ago!
>
>> UK patents max 20 years, US 16 years IIRC.
>
>
>> * Electric and Musical Industries Ltd - registered in England no.53317.
>
> Thompson own the patent for SECAM which might still be in force since it
> dates from 1965/6.
>
> -- 
> From KT24 - in "Leafy Surrey"
>
> Using a RISC OS computer running v5.11
>

"Scott"  wrote in message 
news:6aomhaF3927ctU1@mid.individual.net...
> Charles,
>
> Thanks!  Is SECAM used in France or they are running special system that 
> has very long valid date?
>


The analogue satellite signal on 5w is in Secam.


-- 
Michael Chare

charles wrote:
> Thompson own the patent for SECAM which might still be in force since it
> dates from 1965/6.

That was greater than 40 years ago. Patents, as the post you were 
replying to noted, do not exceed 20 years in the UK or US. In fact this 
limit is true of every significant jurisdiction in the world due to 
international agreements on such matters.

ESB

In article ,
   Scott  wrote:
> Charles,

> Thanks!  Is SECAM used in France or they are running special system that
> has very long valid date?

SECAM (SECquence Avec Memoire) (or commonly: Systeme European Contre les
AMericaines) is a French developed colour system that is broadcast in
France, most of its former colonies and was adopted  (for political
reasons) by the Soviet Union (USSR).  I'm not sure how much of that former
empire still uses SECAM - Russia still does.

Colour television broadcasting began in France in 1968 and pictures from
the Winter Olympics in Grenoble originated in SECAM.

-- 
From KT24 - in "Leafy Surrey"

Using a RISC OS computer running v5.11

charles wrote:

> SECAM (SECquence Avec Memoire) (or commonly: Systeme European Contre les
> AMericaines) is a French developed colour system that is broadcast in
> France, most of its former colonies and was adopted  (for political
> reasons) by the Soviet Union (USSR).

Not entirely political, there was a good technical reason too, some of 
the signal paths are incredibly long in Russia/ex-USSR.
SECAM is better suited than PAL or NTSC because the chrominance signal 
exists in the FM domain, and therefore will not degrade as rapidly as AM 
based PAL and NTSC colour coding.

I'm in an ex-Soviet country right now, and my hosts verify it was more 
of a technical decision than political (according to them :-) ).

In message , Mark Carver 
<mark.carver@invalid.invalid> writes
>charles wrote:
>
>> SECAM (SECquence Avec Memoire) (or commonly: Systeme European Contre les
>> AMericaines) is a French developed colour system that is broadcast in
>> France, most of its former colonies and was adopted  (for political
>> reasons) by the Soviet Union (USSR).
>
>Not entirely political, there was a good technical reason too, some of 
>the signal paths are incredibly long in Russia/ex-USSR.
>SECAM is better suited than PAL or NTSC because the chrominance signal 
>exists in the FM domain, and therefore will not degrade as rapidly as 
>AM based PAL and NTSC colour coding.
>
>I'm in an ex-Soviet country right now, and my hosts verify it was more 
>of a technical decision than political (according to them :-) ).

But aren't things like microwave links FM anyway? Also, at one time, 
some long-reach CATV trunk lines used to transport FM TV signals (a bit 
like analogue satellite).

Haven't some of the ex-Soviets now switched to PAL?
-- 
Ian

In article ,
   Mark Carver <mark.carver@invalid.invalid> wrote:
> charles wrote:

> > SECAM (SECquence Avec Memoire) (or commonly: Systeme European Contre les
> > AMericaines) is a French developed colour system that is broadcast in
> > France, most of its former colonies and was adopted  (for political
> > reasons) by the Soviet Union (USSR).

> Not entirely political, there was a good technical reason too, some of 
> the signal paths are incredibly long in Russia/ex-USSR.
> SECAM is better suited than PAL or NTSC because the chrominance signal 
> exists in the FM domain, and therefore will not degrade as rapidly as AM 
> based PAL and NTSC colour coding.

Well before the adoption of SECAM, the BBC had demonstrated that even NTSC
could be sent happily from London to Moscow and back without degradation. 
On radio links subject to fading, such as the trans (English) Channel,
SECAM suffers serious problems in that the luminance amplitude fades but
the chroma decodes to its intended value.  We used to see that at TV Centre
when we transcoded SECAM signals to PAL.   


> I'm in an ex-Soviet country right now, and my hosts verify it was more 
> of a technical decision than political (according to them :-) ).

they would say that, wouldn't they?

Of course the TV studios in Russia actually make their programmes in PAL ;-)
It's possible to mix coded signals with PAL, for SECAM you need an RGB
mixer ;-(

The political decision is quite obvious when you realise the Cold War was
at its height.  NTSC was from the USA and PAL was from Germany.  Since
France had just left NATO and the General was visiting Moscow to create a
Franco-Soviet pact, the decision to use SECAM came out of that visit.

-- 
From KT24 - in "Leafy Surrey"

Using a RISC OS computer running v5.11

charles wrote:
> In article ,
>    Mark Carver <mark.carver@invalid.invalid> wrote:
>> I'm in an ex-Soviet country right now, and my hosts verify it was more 
>> of a technical decision than political (according to them :-) ).
> 
> they would say that, wouldn't they?
> 
> Of course the TV studios in Russia actually make their programmes in PAL ;-)

Not any more, just about all digital component now, so SECAM only 
appears at the final stage, at the transmitter site. In fact, on my 
travels there's really only one country and broadcaster left that still 
has PAL elements in their Tx chains, some BBC English regional studios.

> It's possible to mix coded signals with PAL, for SECAM you need an RGB
> mixer ;-(

Indeed, some SECAM stations used to take the signal down to YUV, that's 
not quite as 'hairy' as doing it in RGB.

Ian Jackson wrote:

> Haven't some of the ex-Soviets now switched to PAL?

Some have, others have kept SECAM for terrestrial analogue, which just 
as in the UK and W Europe is on its way out anyway.

Ian Jackson wrote:

> 
> But aren't things like microwave links FM anyway? 

They are, but you still need to consider the triangular noise spectrum, 
when transporting 'AM' signals within an FM environment.

A prime example is the stereo difference channel, in the Zenith Pilot 
Tone radio system, we've all witnessed how disproportionally noisy that 
gets once the signal becomes weaker. The difference channel is 
essentially AM at baseband.