Panasonic tc-29g12p User Manual

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TC-20G12P / TC-29G12P / TC-29G12PU

Service Adjustments and Calibrations

AUDIO OUTPUP LEVEL VERIFICATION

REQUIRED EQUIPMENTS / CONNECTIONS:

JIG Filter:

TP18.

RF signal generator:

RF antenna input.

RMS Voltmeter:

Between JIG Filter and GND.

PROCEDURE:

1. Apply the next signals on the antenna input:

Video:

100 IRE Flat Field, 30% modulation.

Audio:

300Hz, 100% modulation, mono

(70±5dB, 75

open, P/S 10dB)

2. Check the Audio level to the

RMS Voltmeter show 150 mVrms.

MTS CIRCUIT ADJUSTMENT

The MTS Circuit adjust of BR2L chasis, is doing through

four steps:

1. VCO Stereo adjustment.

2. Filter adjustment.

3. Input level adjustment.

4. Stereo separation adjustment.

Note: The adjustment must be done in the sequence

showed before. VIF, TP12 (Level Detector) must be

adjusted before MTS adjustment.

STEP 1 VCO STEREO ADJUSTMENT

REQUIRED EQUIPMENTS / CONNECTIONS:

resistive jumper: Connect between the TP14 and GND.

22µF 16V capacitive jumper: Connect between the TP18

(MPX in). and GND.

Frequency Counter: Connect between the TP22 (R-OUT) and

GND.

PROCEDURE:

1. Remove the antenna.

2. On the service mode, select DAC: M1

3. Adjust MTS STEREO PLL VCO DAC: M1 until the

frequency counter show 15.734KHz±50Hz.

(15.684~15784KHz).

Note:

The TV must be turn ON minimum 15 minutes before

adjustment.

STEP 2 FILTER ADJUSTMENT

REQUIRED EQUIPMENTS / CONNECTIONS:

RF Generator: Antenna input (RF)

Oscilloscope: Between TP21 (L-out) and GND.

RMS meter: Between TP18 (MPX-in) and GND.

Note: The GND of oscilloscope must be next of IC2201-01

terminal for minimum noise.

+60

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PROCEDURE:

1. Apply the next signal to antenna input ( RF):

Video: 100 IRE Flat Field, Modulation 30%.

Audio: 15.734KHz sinusoidal wave.

(70±5dB, 75

open, P/S 10dB).

2. Adjust the output level signal generator for that a

15.734KHz wave form be 100 ±5mVrms on TP18.

3. On service mode, adjust DAC: M2.

4. Adjust MTS filter (DAC:M2) until the wave form

amplitude, on oscilloscope screen be minimum.

STEP 3 INPUT LEVEL ADJUSTMENT

REQUIRED EQUIPMENTS / CONNECTIONS:

JIG Filter: Connect to TP22.

RF generator: Connect to RF input antenna terminal.

RMS meter: Between JIG Filter and GND.

PROCEDURE:

1. Apply the next signal on antenna input ( RF):

Video: 100 IRE Flat Field, Modulation 30%.

Audio: 300 Hz, modulation 100%, mono.

(70±5dB, 75

open, P/S 10dB).

2. On service mode, adjust DAC: M0

3. Adjust the input level MTS (DAC: M0) until the Voltmeter

show 212 ± 10.5mVrms.

STEP 4 STEREO SEPARATION ADJUSTMENT

REQUIRED EQUIPMENTS / CONNECTIONS:

RF generator: Antenna input (RF).

Oscilloscope: Between TP22 (R-out) and GND.

PROCEDURE:

1. On audio MENU set STEREO.

2. Apply the next signal on antenna input ( RF):

Video: 100 IRE Flat Field, Modulation 30%.

Audio: 300 Hz, modulation 100%, stereo (L channel)

(70±5dB, 75

open, P/S 10dB).

3. Adjust the low level separation (DAC: M3) until the wave

form amplitude on the oscilloscope screen, be minimum.

4. Adjust the audio of RF generator to 3KHz.

5. Adjust the high level separation (DAC: M4) until the wave

form amplitude on the oscilloscope screen, be minimum.

6. Repeat steps 2 to 4.

TP18

TP22