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Technical Standards



Transmission Standards (Based on ITU-R 450-1)

1. Monophonic transmission

1.1  RF signal carrier frequency –modulated but sound signal with maximum frequency deviation equal to 75 KHz

1.2  Pre-emphasis of the sound signal

Pre-emphasis of the sound signal of 50µs


2 Stereophonic transmission

Pilot –tone system (System 4)

2.1 RF signal

Carrier frequency modulated by stereophonic multiplex signal with a maximum frequency deviation equal to 75 KHz

2.2   Stereophonic multiplex signal is the sum of:

-     the pre-emphasised signal M

-     the side bands of the suppressed sub-carrier amplitude modulated by the pre-emphasised signal S

- a ‘pilot signal’ with a frequency of 19 KHz exactly one half the sub carrier frequency

2.3   Pre-emphasis 50µs

2.4 Amplitude referred to the maximum amplitude of the stereophonic multiplex signal (which corresponds to the maximum frequency deviation )

i) Signal M :90% max (A and B being equal and in phase)

ii) Signal S :maximum value of the sum of the two side bands :90% ( corresponding to A and B being equal and of opposite phase)

iii) Pilot signal :8 to  10 %

iv) Sub carrier at 38 KHz suppressed :maximum residual amplitude 1%

M and S are equal to one half of the sum and one half of the difference of the ‘left hand’,a ‘right `

A and ‘right hand ` , B signals ,respectively .


i) Transmitter Power                                     :           as per plan

ii) Transmit Frequency                                  :            as per  plan

iii) Frequency Tolerance                                :            2kHz (< 50W ,3KHz)

iv) Maximum Deviation                                 :            75KHz

v) Class of Emission                                     :            300KF8E

vi) Bandwidth of Emission                             :           300KHz

vii) Spurious emission                                   :      70dBc and less than .1mW absolute mean power level

Audio quality parameter and target values shall be as contained in ITU-R Recommendation 644

The audio signal level shall be at 0 dB (equivalent to 0.775 volts across 600 ohms) and the signal distribution shall be at +4dB with reference to 0.775 volts



This analogue standard will apply up 17 June 2015


1. Transmission Standard

Colour System:                                                                PAL

Standard:                                                                        ITU-R BT .470 and 472

Code G 625 lines/frame 50fields/s

Nominal radio-frequency channel bandwidth                       8   (MHz)

Sound Carrier relative to vision carrier                               +5.5+/- 0.001MHz

Nearest edge of channel relative to vision carrier                -1.25 MHz

Nominal width of main sideband                                       5 (MHz)

Nominal width of vestigial sideband                                   0.75 (MHz)

Minimum attenuation of vestigial sideband                          20dB (-1.25 MHz)

20 dB (-3.0MHz)

30 dB (-4.43 MHz)

Type and popularity of vision modulations:                        C3F neg

Synchronizing level :                                                        100

Blanking level :                                                                75+/- 2.5

Difference between black level and blanking level:                0 to 2 (nominal)

Peak white level :                                                              F3E

Frequency deviation (KHz):                                                +/- 50

Pre –emphasis for modulation (us)   :                                  50

Ratio of effective radiated power of vision /sound:               10/1

Line frequency fh and tolerance when operated

non synchronously (Hz) :                                                  15625+/- 0.0001%

Maximum variation rate of line frequency valid

for monochrome transmission (% /s)  :                               0.05

2     Equipment

Transmitter power:                                                             as per plan

Transmitter frequency:                                                       as per plan

Frequency tolerance:                                                          500Hz

2kHz <100W pep

5KHz < 1W pep (V)

10 KHz <1 W pep (U)

Spurious emission:60 dBc ,1mW absolute mean power level for

VHF and 12mW for UHF

Video input level:                                                              1V p-p at 75 ohms unbalanced


Transmission equipment shall be capable of being retrofitted to digital transmission.

3 .  Quality

Video quality shall be Betacam SP or any other professional broadcast quality video format

Television studios shall be capable of handling all professional broadcast quality video format and shall be equipped with a standards converter for conversion to the transmission standard.



See section on Digital Broadcasting