CCE HPS-2007 - Page 16

HPS-2007
15
2.3.4 Horizontal Linearity
a) Connect the receiver under test in 117V
AC
line.
Turn on the TV and adjust bright and contrast control to max. position, saturation and
volume to min. Position. Wait for the heat period.
b) Apply to the antenna input a 60dBµV level signal with 88% modulated PHILIPS pattern
(Frequency and channel factory defined)l
c) Adjust bright and contrast control to nominal position
d) For the next reads, please take references by figure D.
e) Observe the screen pattern and check the distances An - 14 blocks (in centimeters)
f) Calculate the middle distances through blocks
M = An/14.
Horizontal deviation between major blocks (DH
M
)
Read first the 14 blocks wide (from b1 to b14) and select the biggest read (b
max
) for calculate
the deviation:
DH
M
= b
máx
/M
Minor Horizontal deviation between blocks (DH
m
)
Read first the 14 blocks wide (from b1 to b14) and select the smallest read (b
min
) for calculate
the deviation:
DH
m
= b
mín
/M
(*)Check for signals PAL-M and PAL-N
PAL-M Minimum Nominal Maximum Unit
DH
M
- 1,10 1,30
DH
m
0,70 0,95 -
PAL-N Minimum Nominal Maximum Unit
DH
M
- 1,10 1,30
DH
m
0,70 0,95 -