Mechanical TV vs Electronic TV

Mechanical TV

• 1884 Paul Nipkow –Invented Nipkow disk

Spinning disk & photoelectronic tubes

improved by Jenkins and Baird in Englandhttp://www.youtube.com/watch?v=92dN2G5-D4c

BellBell LabsLabs

                                                                               

http://www.earlytelevision.org/ge_mechanical.htlhttp://www.earlytelevision.org/ge_mechanical.htl

General Electric

http://www.earlytelevision.org/homemade.html

Mechanical TV had poor picture quality and mechanical parts that

could break or wear out.• Paramount Astoria girls, 21st April 1933

http://www.tvdawn.com/recordng.htmhttp://www.tvdawn.com/recordng.htm

Electronic TV

• Zworykin RCA scientist- iconoscope tube

• Cathode Ray Tube

Philo Farnsworth

• demonstrated the first all-electronic television (1927) basis of

current electronic televisions

• No mechanical parts all electronic

• lost later patent battles to RCA.

Electron Gun

• Scans image

line by line and transmits

convert light into electric signal and sending over by radio waves to a receiver.

Illusion of Motion

• 1877 Edward Muybridge To settle a bet

• Still pictures projected fast seem to move

• Film - 24 frames per second• Television -30 frames per

second

Television and the Depression

1930’s Golden Age of RadioPopular and Profitable

Television technology ready to be introduced but still experimental and expensive.

RCA stalling Farnsworth in court

http://xroads.virginia.edu/~1930s/DISPLAY/39wf/front.htm

1939 Television Introduced 1939 Television Introduced

To prove to To prove to skeptical New skeptical New York World's Fair York World's Fair visitors that no visitors that no trickery was trickery was involved in involved in creating television creating television images, a special images, a special order was made to order was made to RCA's engineering RCA's engineering wing to build a wing to build a transparent transparent version of Vassos' version of Vassos' TRK-12 cabinetTRK-12 cabinet.

www.mztv.com/worldhome.html

  

RCA Pavilion 1939 World’s FairRCA Pavilion 1939 World’s Fair

Very popular exhibit but few TV’s soldVery popular exhibit but few TV’s sold - few programs on air- few programs on air-cost of a TV is the same as a car-cost of a TV is the same as a car

20 April 1939, RCA chairman David Sarnoff20 April 1939, RCA chairman David Sarnoff

http://www.terramedia.co.uk/Chronomedia/picture_pages/1939_worlds_fair.htm

President Franklin Roosevelt, as he appeared on TV screens at the opening of the Fair. It was the first of only two live appearances he made on TV during

his 12 years as President.

http://web.cnjnet.com/~mweinber/nyfair.htmlhttp://web.cnjnet.com/~mweinber/nyfair.html

World War II• 1941 Government stops broadcasts and manufacturing of setsCathode Ray Tubes used for Radar

War improves technologytrains people and brings down price1946 Manufacturing allowed

V.H.F. or U.H.F.

• V.H.F. very high frequency –limited channels with a strong signal

• U.H.F. ultra high frequency – many channels with a weak signal.

• First stations V.H.F. very few stations in a market. Follows the corporate pattern of Radio.

1949 Everything is in place

Signal is standardized Black & WhiteAffordable TV sets ($200-$500)

(Ford car: $1339-$2262)

Locally available

Regular Popular Programming

(Programs sell sets)