I. TELEVISIONHISTORY

II. Early inventions

A. Julius Plucker – 1858

1. His tube

a) Tube with electrodes at either end

b) Sucked out the air

2. Result

a) Fed electricity into the tube

b) Excited the electrons

c) Caused a florescent glow on the walls of the tube

d) The flow of electrons could be moved by a magnet

B. Sir William Crooks – 1875

1. His tube

a) Was used for everything from X-rays to nuclear power experiments

b) A major factor in the invention of television

c) Much like Plucker’s tube

d) Crooks added a gate at one end

2. Result

a) Gate forced electrons into a beam instead of just diffusing them throughout the tube

b) Beam of electrons went from one electrode to the other

c) A magnet made the beam bend in the direction of the magnet

d) Thus, a beam of electrons could be controlled by an electromagnet, a basic necessity for television

C. Karl Braun – 1897

1. Created the cathode ray tube

a) Based on the work of Plucker and Crooks

b) Vacuum tube

c) Electron gun (the diode of the circuit) in one end

(1) Shot out a beam of electrons

(2) Sent to a plate, the anode of the circuit

d) Electromagnets bend the beam of electrons

e) Beam hits a screen painted with florescent paint at the other end of the tube from the electron gun

(1) The beam makes the screen glow where the beam hits

(2) Moving the beam can create glowing lines on the screen

D. Backwards in time

1. Danish researchers in 1873

a) Discovered that the electrical resistance of selenium varies in proportion to the intensity of the light shining on it

b) Can transform light into electrical signals

E. Proposals to transmit pictures by wire

1. G.R. Carey – 1875

a) First attempt to transmit a picture from a camera to a receiver

(1) To capture the image

(a) A mosaic of selenium cells

(b) Each cell connected by wires to a battery and an electric lamp

(c) One lamp for each cell

(d) Cell reacts to light falling on it and sends an electric current

(e) Created an electronic version of a picture from a camera

(2) To receive the image

(a) Current from the selenium cells sent down wire to electric lamps

(b) Lamps would light up in direct proportion of the amount of current

b) Idea wasn’t practical since it would need millions of selenium cells and lamps, each with its own wire, to produce a clear picture

(1) Carey considered scanning the image to reduce the number of cells

2. Shelford Bidwell – 1881

a) Scanning device

(1) Single selenium cell in a camera obscura

(2) Motor drive moves the box up and down rapidly across the plane of the image

(3) Device worked but was limited in speed

b) Maurice leBlanc suggested using an oscillating mirror to reflect the image onto a fixed selenium cell

3. Paul Nipkow – 1884

a) Created the mechanical “television”

(1) Simplest and most workable of the scanning systems proposed

(2) An object is illuminated

(3) Reflected light from the object goes through the holes cut in a spiral in a spinning disk

(4) Light falls on a selenium cell

(5) Current from the cell sent down a wire to a lamp

(6) Light from the lamp shines through a second identical disk of holes

(a) recreating the light from the illuminated object

(b) light shines on a screen

(7) each spin of the disk equals one frame

b) quality of picture was bad

(1) 18 lines per frame compared to todays 525 (1080 in HD)

c) Proved the principle of scanning as viable

F. The creation of actual television (sight at a distance)

1. Nothing happened for 20 years

2. New method – electronic instead of mechanical

a) Boris Rosing of Russia – 1902

(1) Used Braun’s cathode ray tube for image reproduction

(2) 1907 – mechanically produced picture viewed on a cathode ray tube in sync with the sending signal

(3) Arrested by Stalin and sent to Siberia

b) Archibald Campbell-Swinton – 1908

(1) First to suggest using a cathode ray tube at both ends of the system

c) A Sinding-Larsen – 1911

(1) Suggested using radio instead of wires as a carrier for the picture signals

d) All the concepts necessary for TV as we know it are in place

3. World War I interrupts

4. Charles Francis Jenkins – 1923

a) Demonstrates his mechanical TV in the US

b) Used Nipkow’s disk system

5. John Baird – 1923

a) Demonstrates his mechanical TV in England

b) First to televise a face and a moving object

c) Used Nipkow disc and was crude

6. All this activity drew the attention of big corporations

a) Started major development programs

(1) Building labs

(2) Hiring researchers

(3) Dumping in lots of money

b) All came up with mechanical TVs like Nipkow’s

(1) Up to 30 line scans

(2) Pictures still sucked

(3) Disks up to 4 feet across were unpractical

(a) TV was 50”

(b) Screen was 4”

7. Vladimir Zworykin

a) Boris Rosing’s student

b) Apparent patent for his iconoscope in 1923

(1) A cathode ray tube

(2) Could pick up images and convert them to electrical signals

(3) The first camera tube

(4) How it worked

(a) Picture focused on photosensitive mosaic mounted in the tube

(b) Mosaic scanned line by line by an electron beam, releasing a small electric charge from each photoelement

(c) Speed of the beam and the number of lines scanned no longer limited by mechanical considerations

c) Created his kinescope in 1929

(1) A vastly improved cathode ray picture tube

(2) Now the entire system is electronic

8. Philo Farnsworth

a) In 1927 came up with the same ideas as Zworykin

9. Who invented TV – Zworykin or Farnsworth?

a) Zworykin applied for an iconoscope patent in 1923, but it wasn’t granted until 1938

b) Farnsworth challenged Zworykin’s patent in 1934 and won

(1) Zworykin had no evidence that he actually invented a device in 1923 that worked, only his word

(2) Zworykin’s working models only appeared after he visited Farnsworth’s lab in 1930

c) On the basis of the evidence

(1) Farnsworth is the “Father of Television”

(2) Zworykin was the improver for RCA

d) RCA

(1) Zworykin worked for RCA

(2) David Sarnoff

(a) Ran RCA

(b) Thought only RCA should be a force in radio and television

(i) Own all the patents

(ii) Have all the credit

(iii) Thought that RCA should “collect patent royalties, not pay them.”

G. Television enters the market

1. Scanning lines increase in number

a) 1930 – 60 lines

b) 1941 – 525 lines

c) Resolution vastly improved

2. 1939 New York World’s Fair

a) RCA introduces television to the public for sale

(1) Had 441 lines of resolution

(2) Other companies complained

(3) FCC

(a) Rescinded approval for commercial television

(b) An industry committee reviewed standards for manufacture

(i) Approved most of RCA’s standards

(ii) Raised the number of scan lines to 525

(c) Approved the standards and approved commercial TV

b) Then World War II happened

3. 1946 – RCA introduces the “630”

a) 10” screen

b) Improved performaces

c) RCA gave other companies the plans to stimulate production and demand

d) Market exploded

(1) New stations came on the air quickly

(a) Interference problems just like with radio

(b) FCC froze new station construction for a time

(2) 1946 – 6,000 sets in use

(3) 1952 – 22 million sets in use

4. What was on?

a) Radio with pictures

(1) Visuals grab and hold attention in way radio couldn’t even come close to

(2) It didn’t matter what was being shown, only that it was

(3) Novelty quickly palled

b) Programming

(1) All TV programming came out of New York studios

(a) Programs had to fit in the studios

(b) Needed the bright lights

(c) Shows were sent out on the air live

(i) Sitcoms

(a) I Remember Mama

(b) Mr. Peepers

(ii) Dramas

(a) Playhouse 90

(b) Armstrong Circle Theatre

(iii) Comedy-variety shows

(a) Your Show of Shows

(b) Texaco Star Theatre

(2) TV completely changed by I LOVE LUCY and Desi Arnaz

(a) Arnaz and his wife Lucille Ball wanted to do a sitcom

(i) Wanted to live in California

(ii) Wanted to perform the show in front of a studio audience

(iii) Could do neither of these things in New York

(b) Arnaz decided to film the show instead of do it live

(i) Invented the 3 camera technique

(a) 3 cameras film the entire show at the same time

(b) The 3 films are edited to create the actual show

(ii) Fallout from Arnaz’ idea

(a) Everyone wanted to film their shows

(b) Hollywood studios had all the cameras and sound stages needed

(d) The TV industry moves from New York to California

(e) Invention of the rerun

5. The next step – color TV

a) CBS in 1939

(1) Had a color TV system

(a) A wheel with 3 color filters rapidly rotates in front of the camera lens

(b) A similar wheel is used in the receiver

(c) The problems

(i) the system is mechanical

(ii) could get out of synchronization

b) RCA in 1949

(1) An electronic color system

(a) 3 separate pickup tubes in the camera, one for each primary color

(b) 3 kinescopes (one for each color) in the receiver

(c) Required exact – and hard to maintain – alignment

(d) Advantage over CBS’s color wheel system

(i) Compatiblewith existing TVs

(ii) B&W TV could get a good B&W picture

c) FCC gave approval to the CBS system

(1) RCA sued, but lost

(2) CBS went on the air with color in 1950

(a) Nobody went along

(i) Didn’t like the idea of a color wheel in every set

(ii) Wanted backward compatibility

(iii) RCA developed the tri-color kinescope

(a) Only one tube instead of three hard to align tubes

(b) CBS soon gave up

d) National Television Standards Committee (NTSC)

(1) Recommended a set of standards for color TV

(2) Dec. 17, 1953 – FCC approves the start of color TV broadcasting based on NTSC standards

e) NBC started broadcasting in color

f) RCA started selling cameras a transmitting equipment to studios and color TVs to the public

g) Color TV didn’t explode the way B&W had earlier

(1) A matter of money

(a) Producing shows in color cost a lot more

(i) Only a few color sets in use

(ii) Sponsors were reluctant to pay the extra cost

(b) People were reluctant to pay for a color TV when there were so few color shows