[Grovenet] New Broadcast TV (WAS: Get cher coupons here!! Bigblackmarket suretodevelope!! Act now!!)

Wed Jan 2 16:56:08 PST 2008

I was speaking of a practical television system that took off commercially.

TV was described on paper in the 1880's by a fellow named Nipkow and the
name "Television" (distance-seeing) was coined in 1900, I believe. Actually
several inventors were working on it in several countries, but the
technology simply wasn't there yet to support the ideas they had on paper
until the 1930's. It got a huge push from David Sarnoff at RCA who decided
it would be introduced in the late 30's to further bolster RCA's hold on
broadcasting by adding TV to the home radio RCA had promoted (the "Radiola")
since the 1920's. 

The earlier TV systems used mechanical scanners with a disc having holes in
it that passed over a photocell to produce the video image. There were a
variety of on-air tests done here and in Europe. The first ones did nothing
more than produce shadows. Later ones brought some bit of grayscale to the
image, but they were all fuzzy (100 lines of resolution or less compared to
our "fuzzy" 525 line system today) and the mechanical scanning disc limited
the image sizes to no more than a few inches across. 

One advantage was that those low-resolution systems needed little bandwidth
and there were some tests in which a mechanical scan TV signal was actually
transmitted over an AM standard broadcast signal. 

Perhaps I should have commented on the bandwidth we're talking about. A TV
signal using the current broadcast standards requires a bandwidth of 6 MHz.
The AM standard broadcast band is 1 MHz wide, so it requires the spectrum
space taken up by six AM broadcast bands to transmit one TV signal! Only
five TV signals would fit in the entire  radio spectrum known in the 1930s'
-- including the frequencies used for navigation, the standard broadcast
band, and all the short wave frequencies put together! The FM broadcast band
could not handle two TV signals. 

Clearly, one of the essential things needed was more spectrum space, and the
radio spectrum we now call VHF and UHF (Very High Frequencies and Ultra High
Frequencies) provided it. In the late 1930's the radio state of the art set
the maximum commercially usable frequencies at about 30 MHz. WWII caused an
explosion in technology to open higher frequencies for communications and
RADAR. By the end of the war communications equipment operating at 500 MHz
was common, and experiments were being rushed ahead at higher frequencies.
Nowadays we routinely use frequencies as high as 5 or 10 Gigahertz - that's
10,000 MHz! A simple, cheap cell phone works at almost 3 GHz, 3,000 MHz,
these days! 

The opening of VHF/UHF spectrum with literally hundreds of megahertz wide
open made "modern" TV possible in the post WWII years, and the continued
push of technology into higher and higher frequencies is what has made the
new TV standards practical.

At the same time, the mechanical scanner was replaced by an all-electronic
scanning system using specialized vacuum tubes that allowed bigger images
and higher resolutions. These, too, benefited greatly from the technical
work done during the WWII but they were pretty much in place before the war
(and had been demonstrated at the 1938 World's Fair).

Like most technologies, it required the convergence of many things to work
well, and they finally started to come together in the 1930's. 

And there was no shortage of brutal corporate politics in the process,
starting with Sarnoff's outlandish theft of the modern television system
from Philo Farnsworth in order to have RCA control it. Sarnoff simply tied
Farnsworth up in court until he went bankrupt. Farnsworth's heirs kept up
the battle, finally winning recognition of Sarnoff's criminal acts and
control of the patent, but only decades later after it had run out and
become a moot point.

Sarnoff made the guys at Enron look like kindergartners playing in a
sandbox. Shoot, he even coerced President Roosevelt and Congress into making
him a "General" in the USA army with threats and intimidation to withhold
RCA's support for the WWII war effort, then had them identify him as a hero
working for his country! But that's another story...  

Ron D'Eau Claire 

-----Original Message-----
From: grovenet-bounces at rdrop.com [mailto:grovenet-bounces at rdrop.com] On
Behalf Of Steven
Sent: Wednesday, January 02, 2008 3:58 PM
To: Forest Grove local interests list
Subject: Re: [Grovenet] New Broadcast TV (WAS: Get cher coupons here!!
Bigblackmarket suretodevelope!! Act now!!)

Thanks for the history lesson Ron. One note is that Brittan had TV in 1928 I
believe. This was an even poorer signal than the US eventually created. They
stopped broadcasting during wwii and dumped the whole shebang after. That is
when they chose the better system. Japan went with our system, we kinda
forced it on them. One other note is that broadcast TV was invented by a guy
from Idaho. All on his own, no big corp or govt backing. He came up with the
idea of the television scanning system while plowing the potato field. And
of course the first TV Star was Felix the cat. The TV camera required some
3000 ft candles of light so they used a toy doll. FDR was the first
president on TV at the 39 worlds fair. 20 years later most homes still
didn't have TV. Compare that to today and how fast technology grabs hold.

-----Original Message-----
From: grovenet-bounces at rdrop.com [mailto:grovenet-bounces at rdrop.com]On
Behalf Of Ron D'Eau Claire
Sent: Wednesday, January 02, 2008 3:45 PM
To: 'Forest Grove local interests list'
Subject: [Grovenet] New Broadcast TV (WAS: Get cher coupons here!! Big
blackmarket suretodevelope!! Act now!!)

A lot of people don't realize the USA has the most antiquated television
broadcasting system standards in the world for two reasons:

1) The USA was the first to implement technical standards for TV
broadcasting. That was in the 1930's!

2) In establishing the TV standards they faced same issue we do with the
internet today: bandwidth. Speed wasn't a variable if one wanted motion
pictures that didn't jerk, so the tradeoff was between image quality and
bandwidth. The FCC did a lot of looking around and, since television was to
be a home entertainment medium, they asked "What sort of pictures will
people accept in their homes?" In the 1930's the latest and greatest
technology for "home entertainment" was 8-mm "home movies". They were black
and white movies on tiny 8-mm wide film (1/2 the width used by most
industrial/military films and 1/4 the size of film used in theatres). The
smaller film was cheaper, but the small size meant grainer, fuzzier
pictures. Still people who could afford it flocked to use the technology. So
the TV standards were designed to produce pictures that would approximate
the quality of 8-mm home movies.

It's amazing what the engineers managed to cram into the same television
signal spectrum bandwidth over the years since: color imaging, subtitles,
stereo sound, timing signals, etc. All through the years the FCC has
insisted that the TV broadcast bandwidth remain the same using the same
frequency (channel) assignments and that the video and audio signal formats
be "backwardly compatible" so that a set made in 1945 could receive a TV
signal transmitted today. The only real change was to drop Channel 1 shortly
after WWII for a variety of technical reasons the prewar engineers hadn't
anticipated.

In the subsequent years big problem was to add color. That did result in a
poorer quality signal, but a color one. Engineers noted that we humans have
terrible visual acuity in the red end of the spectrum. If we go into a room
illuminated by red light, everything looks rather soft and indistinct. By
contrast, blue light brings out detail and sharpness in what our eyes see.
So the engineers first reduced the overall picture "sharpness" to save a bit
of bandwidth, making the pictures fuzzier than they were previously in black
and white, then they used the bandwidth saved to integrate a color image
carefully shaped to match our eyesight. The red parts of your TV image are
very poor quality, lacking almost all detail, since your eyes can't see any
better in red anyway. Other colors had detail to match eyesight fairly well
too.

The end result was that a color TV picture could be watched in black and
white on an old set, but it looked less sharp than before. That didn't
matter, people were ecstatic over color images and when some people
complained that their black and white TV pictures weren't as sharp as before
they were told to buy a color set. The brilliant NBC Peacock of the 1960's
was here to stay.

Other countries, such as England, Europe and South America standardized
their TV systems  after we did, building on things we discovered were
less-than-ideal. From the outset they adopted a standard for sharper images
and then they adopted a different color system that wasn't exactly backward
compatible but which produced superior color fidelity to ours. European TV
using SECAM or PAL color systems have consistently make American TV look
obviously soft and fuzzy. Blowing up our fuzzy pictures on bigger screens
when the projection TV craze hit didn't help. Clearly American TV was
bad-looking TV.

Finally, 70 years after the US technical standards for broadcast TV were
adopted, they are for the first time being updated.

I wonder how long the new standards will last?

Ron D'Eau Claire

-----Original Message-----

Actually, TV could use a boost of technology and there isn't much room at
the current location. In fact ch 2-6 are one spectrum, 7-13 another and
14-69 a whole nother one. This has been in the works for over a decade and
has actually been postponed a few years already. But there is a giveaway.
Low Power TV. This is kind of a mop & pop TV broadcasting. The government
has set aside $65M to assist these little stations to move to the digital
world. I can see this getting some folks to buy existing LPTV setups just so
they can get in on this cow.
  -----Original Message-----

_______________________________________________
GroveNet mailing list
GroveNet at rdrop.com http://www.rdrop.com/mailman/listinfo/grovenet

_______________________________________________
GroveNet mailing list
GroveNet at rdrop.com http://www.rdrop.com/mailman/listinfo/grovenet