
Parameter
Symbol
Measurement
Input signal
Measurement procedure
Bus and other conditions
point
[Chroma Block]
Bout
C-1
Measure the output amplitudes when the
ACC amplitude characteristic 1
ACCM1
0 dB
chrominance signal input is 0 dB and when
+6 dB
that input is +6 dB and calculate the ratio.
ACCM1 = 20
× log (+6 dBdata/0dBdata)
Bout
Measure the output amplitude when the
ACC amplitude characteristic 2
ACCM2
C-1
chrominance signal input is –14 dB and
–14 dB
calculate the ratio.
ACCM2 = 20
× log (–14 dBdata/0dBdata)
YIN: L77
C-1:
Measure the Y output level
No signal
(Record this measurement as V1)
B-Y/Y amplitude ratio
CLRBY
Next, input a signal to CIN, and (with YIN a
sync-only signal) measure the output level.
C-2
(Record this measurement as V2)
Calculate CLRBY from the following formula.
CLRBY = 100
× (V2/V1) + 15%
Measure V1: the output amplitude when the
TR24:
color control is maximum, and V2: the output
Saturation
Color control characteristic 1
CLRMN
C-3
amplitude when the color control is nominal.
01111111
Calculate CLRMN as V1/V2.
Saturation
01000000
Measure V3: the output amplitude when the
TR28:
Color control characteristic 2
CLRMN
C-3
color control is minimum. Calculate CLRMM
Saturation
as CLRMN = 20
× log (V1/V3).
00000000
Measure V4: the output amplitude when the
TR24:
color control is 90, and V5: the output amplitude Saturation
Color control sensitivity
CLRSE
C-3
when the color control is 38. Calculate CLRSE
01011010
from the following formula.
Saturation
CLRSE = 100
× (V4 – V5)/(V2 × 52)
00100110
Tint center
TINCEN
C-1
Measure all sections of the output waveform
TR23: Tint
and calculate the B-Y axis angle
00111111
Measure all sections of the output waveform,
Tint control maximum
TINMAX
C-1
calculate the B-Y axis angle, and calculate
TR23: Tint
TINMAX from the following formula.
01111111
TINMAX = <the B-Y axis angle> – TINCEN
Measure all sections of the output waveform,
Tint control minimum
TINMIN
C-1
calculate the B-Y axis angle, and calculate
TR23: Tint
TINMIN from the following formula.
00000000
TINMIN = <the B-Y axis angle> – TINCEN
Measure A1: the angle when the tint control is 85,
TR23: Tint
Tint control sensitivity
TINSE
C-1
and A2: the angle when the tint control is 42,
01010101
and calculate TINSE from the following formula.
00101010
TINSE = (A1 – A2) /43
Demodulation output ratio
RB
C-3
Measure Vb: the BOUT output amplitude,
TR24:
R-Y/B-Y
and Vr: the ROUT output amplitude.
Saturation
Determine RB = Vr/Vb.
01000000
Demodulation output ratio
Measure Vg: the GOUT output amplitude and
TR24:
G-Y/B-Y
GB
C-3
determine GB = Vg/Vb
Saturation
01000000
No. 5844-16/27
LA76070
Continued on next page.
30
29
28