Those were the days!

Rick wrote:


wrote in message
...
Quite impressive though that a PAL colour signal could be decoded by
a
valve based system inside a box that could fit inside a house.
Albeit a
large box.


Fortunately the only valve decoder I can remember was in the monstrous
Philips G6, and IIRC even that used around half a dozen transistors as
well.

I recall seeing an American all-valve colour TV around 1970. It had
weird valves with multiple elements in one envelope, and with almost as
many pins as a modern microprocessor. Unfortunately someone had plugged
it into the 240v mains...
--
Dave

In article , d
scribeth thus
On Tue, 21 Jun 2011 11:25:35 +0100
Bill Wright wrote:
you had a spare bedroom for the engineer. The UK sets had a large number
of valves which meant that they ran very hot and also needed frequent
valve changes. I used to deliver sets for several firms and only the

Quite impressive though that a PAL colour signal could be decoded by a
valve based system inside a box that could fit inside a house. Albeit a
large box.

If someone tried to do it today from scratch no doubt they'd spec up some high
powered CPU + DSP with god knows how many megabytes of buggy software that
had to be upgraded every month otherwise the picture would occasionally
invert or spin like a top or however overly complex software ends failing.

B2003


Ummm ... Isn't that what they do anyway?...
--
Tony Sayer

On Jun 21, 1:50*am, Kennedy McEwen wrote:
In article , R. Mark Clayton
writes


Being adopted as a European standard a decade or so after the US
standardised NTSC enabled PAL to be higher resolution, at 625 lines, as
well.
--

Actually the European 625-line standard, or '576i' in new money, came
about because it allowed nearly the same line scanning frequency, for
50 Hz field scanning, as the established American 525-lines did on 60
Hz, so that American components, such as LOPT's and scanning coils,
could be supplied to Europe to help rebuild the economies after the
destruction of WW2.

On Tue, 21 Jun 2011 05:12:55 -0700 (PDT)
"alexander.keys1" wrote:
Actually the European 625-line standard, or '576i' in new money, came
about because it allowed nearly the same line scanning frequency, for
50 Hz field scanning, as the established American 525-lines did on 60
Hz, so that American components, such as LOPT's and scanning coils,
could be supplied to Europe to help rebuild the economies after the
destruction of WW2.

If thats all there was to it why didn't they just adopt NTCS an be done
with it then like Japan did?

B2003

On Tue, 21 Jun 2011 13:09:55 +0100
tony sayer wrote:
If someone tried to do it today from scratch no doubt they'd spec up some
high
powered CPU + DSP with god knows how many megabytes of buggy software that
had to be upgraded every month otherwise the picture would occasionally
invert or spin like a top or however overly complex software ends failing.

B2003


Ummm ... Isn't that what they do anyway?...

Is it? I assumed modern TVs that still decode analogue have a built in
PAL decoder that simply writes direct into the video memory for display.
Trying to do it in software seems a pretty dumb thing to do.

B2003

In article , d
scribeth thus
On Tue, 21 Jun 2011 13:09:55 +0100
tony sayer wrote:
If someone tried to do it today from scratch no doubt they'd spec up some
high
powered CPU + DSP with god knows how many megabytes of buggy software that
had to be upgraded every month otherwise the picture would occasionally
invert or spin like a top or however overly complex software ends failing.

B2003


Ummm ... Isn't that what they do anyway?...

Is it? I assumed modern TVs that still decode analogue have a built in
PAL decoder that simply writes direct into the video memory for display.
Trying to do it in software seems a pretty dumb thing to do.


Nah!, It was a reference to the buggy software that needs sat boxes and
PVR's to be upgraded every 5 mins;!...

B2003


--
Tony Sayer

In message , d
writes
On Tue, 21 Jun 2011 05:12:55 -0700 (PDT)
"alexander.keys1" wrote:
Actually the European 625-line standard, or '576i' in new money, came
about because it allowed nearly the same line scanning frequency, for
50 Hz field scanning, as the established American 525-lines did on 60
Hz, so that American components, such as LOPT's and scanning coils,
could be supplied to Europe to help rebuild the economies after the
destruction of WW2.

If thats all there was to it why didn't they just adopt NTCS an be done
with it then like Japan did?

Would it not have saved everyone a lot of time and effort if the rest of
the world had adopted the 'modified' American 525-line System M standard
- System N (625-line, 25/50Hz PAL instead)? With shadow-mask CRTs, the
reduction of horizontal resolution would have been hardly noticeable.
http://en.wikipedia.org/wiki/Broadca...vision_systems
--
Ian

On Tue, 21 Jun 2011 13:45:52 +0100
tony sayer wrote:
Nah!, It was a reference to the buggy software that needs sat boxes and
PVR's to be upgraded every 5 mins;!...

Thats what I was thinking about when I originally posted. I own a Humax.
Nuff said!

B2003

"Ian Jackson" wrote in message
...
Would it not have saved everyone a lot of time and effort if the rest of
the world had adopted the 'modified' American 525-line System M standard -
System N (625-line, 25/50Hz PAL instead)? With shadow-mask CRTs, the
reduction of horizontal resolution would have been hardly noticeable.
http://en.wikipedia.org/wiki/Broadca...vision_systems

I thought that PAL was designed as an improvement on NTSC in that it has the
phase-alternating of one of the colour components so that systematic phase
errors in the broadcast network don't manifest themselves as shifts of hue
(hence the nickname Never The Same Colo(u)r) but instead produce much less
noticeable reduction in saturation.

The compatibility problem is 625/25 versus 525/30 because it requires line-
and frame-interpolation. In contrast, conversion between NTSC and PAL at the
same line/frame rate is fairly trivial.

In article
,
alexander.keys1 wrote:
Actually the European 625-line standard, or '576i' in new money, came
about because it allowed nearly the same line scanning frequency, for
50 Hz field scanning, as the established American 525-lines did on 60
Hz, so that American components, such as LOPT's and scanning coils,
could be supplied to Europe to help rebuild the economies after the
destruction of WW2.

Sounds unlikely. You re-build an economy by making parts for luxury items
in that country rather than importing them. Have you any examples of this
having taken place? The equipment to wind transformers etc would be an
early purchase for an electronic parts maker, given they are specialised
high cost units.

--
*Before they invented drawing boards, what did they go back to?

Dave Plowman London SW
To e-mail, change noise into sound.