HPS-2971
Point X, Y LIMITS (mm)
BG, RG BG
a 0,4 0,4
b, c 1,2 1,2
d, e 1,0 1,0
f, g, h, j 1,5 2,0
f’, g', h', j' 1,2 1,5
k, l, m, n 1,2 1,2
s, t, u, v 1,0 1,0
3.6 Video
3.6.1 Sensibility and Signal /Noise Rate
a) Adjust the TV to a “PP” condition.
b) Apply to the antenna input a 60dBµV signal with 88% AM modulation, 1kHz
sine wave (frequency and channel factory defined).
c) Connect at the output video detector an AC voltmeter and read the voltage
V
AC.
d) Turn off the AM modulation and read the noise level “Vr” (AC voltmeter)
.
e) Calculate the signal-noise rate as following:
S/N=20 log (V
AC
/ V
R
).
f) Reduce the output level signal generator till the rate S/N reach 20 dB. In
this condition the output level signal generator is the sensibility in dBuV.
Minimum Nominal Maximum Unit
Sensibility - 37,00 46,00
dBµV
S/N 40,00 50,00 - dB
3.6.2 Chrome sensibility
a) Adjust the TV to a “PP” condition.
b) Apply to the antenna input a 60dBµV signal with 88% AM modulation with
PAL-M color pattern (frequency and channel factory defined), and FM sine
wave 400Hz audio modulation +-25 kHz deviation.
c) Observe the TV screen under test and reduce the output generator level
until the color pattern be visible. At this condition the output generator level
represents the sensibility of chrome in dBµV.
Note: If the TV under test is two or three-system mode, repeat this procedures
for the PAL-N and NTSC-M signal system.
Condition Minimum Nominal Maximum Unit
PAL-M - 28,00 30,00
dBµV
PAL-N - 28,00 30,00
dBµV
NTSC-M - 28,00 30,00
dBµV
3.6.3 Sensibilidade de recepção de Closed Caption
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