COURSE: AUDIO VIDEO ENGINNERING TV Transmitter and Receiver COURSE CODE: 17537 Chapter Name of the Topic Hours Marks  1. Hi Fi Audio Amplifier 07 12  2. CD player 05  3. TV Fundamentals 09 20  4. TV Transmitter and Receiver  5. Colour TV  6. Cable Television 06 16   TOTAL 48 100 12 November 201812 November 2018

Learning Resources: 12 November 201812 November 2018

COURSE: AUDIO VIDEO ENGINNERING CHAPTER : 3. TV Fundamentals COURSE CODE: 17537 CHAPTER : 3. TV Fundamentals Marks: 20 Marks. Contents: Basic fundamentals of colour & monochrome television. Colour theory, Grass man’s law & colour mixing. Composite Video Signal (CVS). TV channel allocation for band I & band III. 12 November 201812 November 2018

Basic fundamentals of colour & monochrome television. ASPECT RATIO: The aspect ratio of an image describes the proportional relationship between its width and its height. TV Fundamentals 12 November 201812 November 2018

Persistence of Vision Basic Concept Example IMAGE CONTINUITY: TV Fundamentals 12 November 201812 November 2018

Progressive Scanning: Interlace Scanning: SCANNING: It is a process of converting image in to equivalent electrical signal. Progressive Scanning: Interlace Scanning: TV Fundamentals 12 November 201812 November 2018

Interlaced Scanning: ODD lines are scanned first Then EVEN lines are scanned TV Fundamentals 12 November 201812 November 2018

Interlaced Scanning line details: TV Fundamentals 12 November 201812 November 2018

VERTICAL TRACE & RETRACE: TV Fundamentals 12 November 201812 November 2018

VERTICAL & HORIZONTAL TIME PERIOD: TV Fundamentals 12 November 201812 November 2018

Vertical resolution. The extent to which the scanning system is capable of resolving picture details in the vertical direction is referred to as its vertical resolution. the vertical resolution is a function of the scanning lines into which the picture is divided in the vertical plane. The vertical resolution in the 625 lines system can then be expressed as Vr = Na × k where Vr is the vertical resolution expressed in number of lines, Na is the active number of lines and k is the resolution factor (also known as Kell factor ). Assuming a reasonable value of k = 0.69, Vr = 585 × 0.69 = 400 lines TV Fundamentals 12 November 201812 November 2018

Horizontal resolution Horizontal resolution. The capability of the system to resolve maximum number of picture elements along the scanning lines determines horizontal resolution. This can be evaluated by vertical and horizontal resolution and as such the number of alternate black and white bars. that should be considered is equal to Na × aspect ratio = 585 × 4/3 = 780 Contrast. This is the difference in intensity between black and white parts of the picture over and above the brightness level. Luminance or Brightness This is the amount of light intensity as perceived by the eye regardless of the colour. In black and white pictures, better lighted parts have more luminance than the dark areas. TV Fundamentals 12 November 201812 November 2018

Hue Saturation Compatibility This is the predominant spectral colour of the received light. Thus the colour of any object is distinguished by its hue or tint. Saturation This is the spectral purity of the colour light. Since single hue colours occur rarely alone, this indicates the amounts of other colours present. Thus saturation may be taken as an indication of how little the colour is diluted by white. Compatibility Compatibility implies that The colour television signal must produce a normal black and white picture on a monochrome receiver without any modification of the receiver circuitry and A colour receiver must be able to produce a black and white picture from a normal monochrome signal. This is referred to as reverse compatibility. TV Fundamentals 12 November 201812 November 2018

To achieve this, that is to make the system fully compatible the composite colour signal must meet the following requirements: It should occupy the same bandwidth as the corresponding monochrome signal. The location and spacing of picture and sound carrier frequencies should remain the same. The colour signal should have the same luminance (brightness) information as would a monochrome signal, transmitting the same scene. The composite colour signal should contain colour information together with the ancillary signals needed to allow this to be decoded. The colour information should be carried in such a way that it does not affect the picture reproduced on the screen of a monochrome receiver. The system must employ the same deflection frequencies and sync signals as used for monochrome transmission and reception. TV Fundamentals 12 November 201812 November 2018

3 to 8 times the picture height. Viewing distance. The viewing distance from the screen of the TV receiver should not be so large that the eye cannot resolve details of the picture. The distance should also not be so small that picture elements become separately visible. The above conditions are met when the vertical picture size subtends an angle of approximately 15° at the eye. The distance also depends on habit, varies from person to person, and lies between 3 to 8 times the picture height. Most people prefer a distance close to five times the picture height. TV Fundamentals 12 November 201812 November 2018

BOTH SIDEBAND contains same information Vestigial sideband transmission: LSB USB BOTH SIDEBAND contains same information TV Fundamentals 12 November 201812 November 2018

So the Bandwidth utilization will be more & there will be wastage of BANDWIDTH To avoid dis….. LSB USB Bandwidth saved TV Fundamentals 12 November 201812 November 2018

TV Fundamentals 12 November 201812 November 2018

TV Fundamentals 12 November 201812 November 2018

C.C.I.R. Standards for 625-B System CCIR:- International Radio Consultative Committee No. of lines per picture (frame) 625 Field frequency (Fields/second) 50 Interlace ratio, i.e., No. of fields/picture 2/1 Picture (frame) frequency, i.e., Pictures/second 25 Line frequency and tolerance in lines/second, 15625 ± 0.1% (when operated non-synchronously) Aspect Ratio (width/height) 4/3 Scanning sequence (i) Line : Left to right (ii) Field : Top to bottom TV Fundamentals 12 November 201812 November 2018

Approximate gamma of picture signal 0.5 System capable of operating independently of power supply frequency YES Approximate gamma of picture signal 0.5 Nominal video bandwidth, i.e., highest video modulating frequency (MHz) 5 Nominal Radio frequency bandwidth, i.e., channel bandwidth (MHz) 7 Sound carrier relative to vision carrier (MHz) + 5.5 Sound carrier relative to nearest edge of channel (MHz) – 0.25 Nearest edge of channel relative to picture carrier (MHz) –1.25 Fully radiated sideband Upper Nominal width of main sideband (upper) (MHz) 5 Width of end-slope of full (Main) sideband (MHz) 0.5 Nominal width of vestigial sideband (MHz) 0.75 Vestigial (attenuated) sideband Lower Television Fundamentals 12 November 201812 November 2018

Min : attenuation of vestigial sideband in dB, (at 1.25 MHz) 20 dB. below the ideal demodulated curve) (at 4.43 MHz) 30 dB Width of end-slope of attenuated (vestigial) sideband (MHz) 0.5 Synchronizing level as a percentage of peak carrier 100 Blanking level as percentage of peak carrier 72.5 to 77.5 Difference between black and blanking level as a percentage of peak carrier 0 to 7 Peak white level as a percentage of peak carrier 10 to 12.5 Type of sound modulation FM, ± 50 KHz Pre-emphasis 50 μs Resolution 400 max Ratio of effective radiated powers of vision and sound 5/1 to 10/1 TV Fundamentals 12 November 201812 November 2018

Course: AUDIO VIDEO ENGINNERING CHAPTER : 3. TV Fundamentals Course CODE: 17537 CHAPTER : 3. TV Fundamentals Marks: 20 Marks. Contents: Basic fundamentals of colour & monochrome television. Colour theory, Grass man’s law & colour mixing. Composite Video Signal (CVS). TV channel allocation for band I & band III. 12 November 201812 November 2018

The Visible Spectrum TV Fundamentals 12 November 201812 November 2018

Colour theory, Grass man’s law & colour mixing. The property of the eye of producing a response which depends on the algebraic sum of the red, green and blue inputs is known as Grassman's Law. TV Fundamentals 12 November 201812 November 2018

EXAMPLE Subtractive Theory Additive Theory The subtractive, or pigment theory deals with how white light is absorbed and reflected off of colored surfaces. Additive Theory The Additive, or light theory deals with radiated and filtered light. EXAMPLE TV Fundamentals 12 November 201812 November 2018

Course: AUDIO VIDEO ENGINNERING CHAPTER : 3. TV Fundamentals Course CODE: 17537 CHAPTER : 3. TV Fundamentals Marks: 20 Marks. Contents: Basic fundamentals of colour & monochrome television. Colour theory, Grass man’s law & colour mixing. Composite Video Signal (CVS). TV channel allocation for band I & band III. 12 November 201812 November 2018

Composite Video Signal (CVS). With P/S Ratio = 10/4 TV Fundamentals 12 November 201812 November 2018

Blanking Pulse: TV Fundamentals 12 November 201812 November 2018

Horizontal sync detail: TV Fundamentals 12 November 201812 November 2018

Vertical Sync details TV Fundamentals 12 November 201812 November 2018

TV Fundamentals 12 November 201812 November 2018

TV Fundamentals 12 November 201812 November 2018

Equalizing pulses: TV Fundamentals 12 November 201812 November 2018

TV Fundamentals 12 November 201812 November 2018

Colour Burst signal: TV Fundamentals 12 November 201812 November 2018

Course: AUDIO VIDEO ENGINNERING CHAPTER : 3. TV Fundamentals Course CODE: 17537 CHAPTER : 3. TV Fundamentals Marks: 20 Marks. Contents: Basic fundamentals of colour & monochrome television. Colour theory, Grass man’s law & colour mixing. Composite Video Signal (CVS). TV channel allocation for band I & band III. 12 November 201812 November 2018

Picture carrier Frequency TV channel allocation for band I & band III. Band Channel No. Frequency range Picture carrier Frequency (MHz) Sound carrier Frequency (MHz) BAND I (41-68 MHz) 1 41–47 (not used) 2 47–54 48.25 53.75 3 54–61 55.25 60.75 4 61–68 62.25 67.75 BAND III (174–230 MHz) 5 174–181 175.25 180.75 6 181–188 182.25 187.75 7 188–195 189.25 194.75 8 195–202 196.25 201.75 9 202–209 203.25 208.75 10 209–216 210.25 215.75 11 216–223 217.25 222.75 12 223–230 224.25 229.75 TV Fundamentals 12 November 201812 November 2018

Course: AUDIO VIDEO ENGINNERING CHAPTER : 3. TV Fundamentals Course1 CODE: 17537 CHAPTER : 3. TV Fundamentals Marks: 20 Marks. Contents: Basic fundamentals of colour & monochrome television. Colour theory, Grass man’s law & colour mixing. Composite Video Signal (CVS). TV channel allocation for band I & band III. 12 November 201812 November 2018