
Continued from preceding page.
Parameter
Symbol
Input Output
Conditions
min
typ
max
Unit
REC AFC pull-in range
fAFC1
T37A
T24
Input a string of pulses (negative polarity) at
300 mV, 15.6 kHz with a width of 5 s. After
increasing the frequency of the pulse string
until the waveform at pin 24 is disrupted,
then reduce the frequency until the waveform
at pin 24 is normal again; that pulse string
frequency is f1.
fAFC1 =f1 – 15.625 (kHz)
1.0
7.0
kHz
fAFC2
T37A
T24
In the same manner, after reducing the
frequency of the pulse string until the
waveform at pin 24 is disrupted, then
increase the frequency until the waveform at
pin 24 is normal again; that pulse string
frequency is f2.
fAFC2 =f2 – 15.625 (kHz)
–3.7
–1.0
kHz
[PB Mode Chroma]
PB chroma video output
level
Vop-34
T39A
T15A
T4A
T34A In PB, SP mode, input a 4 MHz: 300 mVp-p
continuous wave at T39A, and from T15A
input a chroma signal (SP mode, burst 50
mVp-p) that underwent low-band conversion
from a chroma noise test signal.
Input a 50% white signal from T4A and
measure the T34A burst level
240
300
360 mVp-p
PB chroma pin 31 output
level
Vop-31
T39A
T15A
T4A
T31
Measure the T31 burst level under the same
conditions as for Vop-34.
220
270
320 mVp-p
PB ACC characteristics
ACCP1
T39A
T15A
T4A
T31
Input the input chroma level at +6 dB under
the same conditions as for Vop-34 and
measure the T31 burst level, and calculate
the ratio with Vop-31.
0.5
0.8
dB
ACCP2
T39A
T15A
T4A
T31
Input the input chroma level at –6 dB under
the same conditions as for Vop-34 and
measure the T31 burst level, and calculate
the ratio with Vop-31.
–0.5
–0.2
dB
PB killer input level
VACK-P
T39A
T15A
T4A
T31
Lower the input chroma level under the same
conditions as for Vop-34 and measure the
input burst level at the point where T31
chroma output ceases. (Calculate ratio with
standard input of 50 mVp-p)
–40
–32
–25
dB
PB killer chroma output
level
VOACK-P
T39A
T15A
T4A
T34A Use a spectrum analyzer to measure the T34
chroma output level in the killer state
described previously. Calculate ratio with
VOP-34.
–44
–40
dB
PB main converter carrier
leak
CLP
T39A
T14A
T4A
T34A Monitor T34A with a spectrum analyzer under
the same conditions as for Vop-34 and
calculate the ratio between the 4.43 MHz
component and the 5.06 MHz carrier leak
component.
–40
–33
dB
Burst de-emphasis amount
(NTSC mode)
GBD
T39A
T4A
T27A
T31
From T39A, input a 4 MHz 300 mVp-p
continuous wave; from T4A, input a 50%
white signal, and calculate the ratio between
the output level during the T31 burst interval
and the output level during other intervals.
–4.40 –4.65 –4.90
dB
PB XO output level
VXO-P
T19
Measure the PB mode T19 output level with
an FET probe
480
610
750 mVp-p
PB XO oscillation frequency
variation
fXO
T19A Measure the frequency at T19A during PB
mode...f
fXO = f – 4433619 (Hz)
–9
0
+9
Hz
Continued on next page.
LA7391AN
No. 3951-6/11