Panasonic OmniVision PV-M1347, Service Manual

Page: 46 / 143

2-28
20mV
1ms
TP4202(R CH)
Minimum
1V
20
µ
s
Pin 5 of PK5
or TP49
A
SEPARATION ADJUSTMENT
(Model: I)
Purpose:
To separate the L and R Channels of Stereo Signal.
Symptom of Misadjustment:
The L and R Channels of Stereo Signal will not be separated
properly resulting in no stereophonic effect.
Test Point : TP4202 (TV Stereo C.B.A.)
Adjustment : R4901 (TV Stereo C.B.A.)
Specification: minimum level
INPUT
: Antenna Input Terminal
MTS (ONLY L CH)
300Hz +/- 5Hz
14% or 7% Modulating
Mode : STOP
Equipment : Oscilloscope, MTS/SAP Signal Generator
1. Connect the RF OUTPUT of the MTS/SAP Signal
Generator to the Antenna Input Terminal.
2. Connect the Oscilloscope to TP4202(R CH) on the TV
Stereo C.B.A.
3. Adjust R4901 on the TV Stereo C.B.A. so that the signal
level is minimum.
Fig. E4
SUB CONTRAST ADJUSTMENT
Purpose:
To set the optimum sub contrast level.
Symptom of Misadjustment:
The picture is too dark or too light.
Test Point : Pin 5 of PK5 (TV Main C.B.A.)
or TP49 (CRT C.B.A.)
Adjustment : SUB CONTRAST (EVR)
Specification: 3.0 +/- 0.1Vp-p
Input
: Video Input Jack
Crosshatch Pattern Signal 1Vp-p
(75 ohm terminated)
Mode : STOP
Equipment : Oscilloscope
1. Reset the control levels to the factory-set levels using the
remote control as follows.
1) Press the MENU key to display the MAIN menu.
2) Select "TV" and then, press the MENU key to display
the SET UP TV menu.
3) Press the CH UP/DOWN key to select the VIDEO
ADJUST. Then, press the VOL UP key to display the
VIDEO ADJUST mode.
4) Press the CH UP/DOWN key to select "NORMAL."
Then, press the VOL UP key to return the levels to the
factory-settings.
2. Supply a Crosshatch Pattern Signal to the Video Input
Jack.
3. Connect the Oscilloscope to Pin 5 of PK5 on the TV Main
C.B.A. or TP49 on the CRT C.B.A.
4. Select SUB BRIGHT in EVR adjustment mode. Then, after
making a note of the original value, adjust to the minimum
(C0).
5. Select SUB CONTRAST in EVR adjustment mode and
adjust so that the level A is 3.0 +/- 0.1Vp-p.
6. Select SUB BRIGHT in EVR adjustment mode and reset to
the original value.
Fig. E5
FM VCO ADJUSTMENT (Model: I)
Purpose:
To set VCO free run frequency.
Symptom of Misadjustment:
Even when stereophony is received, only monaural sound
will be output.
Test Point : Pin 4 of P4201,
TP9201 (TV Stereo C.B.A.)
Adjustment : R9206 (TV Stereo C.B.A.)
Specification: 38.10kHz +/- 50Hz
Mode
: -------------
Equipment : Frequency Counter
1. Disconnect Connector PK2 on the TV Main C.B.A.
2. Connect Pin 4 of P4201 to GND.
1
8
P4201
GND
4 pin
3. Connect TP9201 to GND through a resistor (3.3k ohm).
Then, connect Frequency Counter to TP9201.
4. Adjust R9206 (FM VCO) so that the frequency is 38.10kHz
+/- 50Hz.
5. Connect Connector PK2 after this adjustment is complete.
GND
TP9201
Frequency Counter
3.3k
Ω