SHARP 14D2GA
Manual de Servicio

PURITY ADJUSTMENT ADJUSTMENT PRECAUTION:
1 PURITY ADJ. 1. Receive GREEN-ONLY signal. Adjust the beam current to about 500 µA. 2. Degauss CRT enough with the degausing coil.

Make sure TV Set is in "Normal Condition" before switch to service mode for adjustNo. point Adjusting procedure/conditions Waveform and others ment.

a b
Note: Follow the Job Instruction Sheet to adjust the magnetic field. 3. Maintain purity magnet at the zero magnetic field and keep the static convergence roughly 1 Tuner IFT 1. Get tuner ready to receive the CH. E 9 adjusted. ( PRESET ) signal,but with no signal input. 4. Observe the points a, b as shown in Fig. 4-1 Adjust the PLL data.
Oscilloscope IF OUT

PIF ADJUSTMENT

No. point Adjusting procedure/conditions Waveform and others

2. Connect the sweep generator's output cable to 1n60 1000p through microscope. Adjust landing to the 10k 5. Orient the raster rotation to 0 eastward.
100k 75ohm

Fig. 4-1

the tuner antenna. ( RF SWEEP ) rank A requirements. 6. Tighten up the deflection coil screws. 3. Adjust the sweep generator's to 80dBuV. 4. Connect the response lead ( use LOW IMPED-

ANCE probe with wave detector ; see Fig.1 ) to » Tightening torque: 108 20 N (11 ± 2 kgf) A the tuner's IF output terminal. ( This terminal Fig.1 7. Make sure CRT corners landing meet the A rank requirements. If not, stick the magnet sheet must have the probe alone connected ). to correct it. 5. Set the RF AGC to 0 6 V no saturation with B Note: This adjustment must be done after the waveform. longer with a beam current over 500 µA. shown in Fig. 2. -1.5+/-0.8dB Fig.2 * For the following colours press R/C RGB key to Fig. 4-2 Note: Be sure to keep the tuner cover in position

E-9 CH

6. Adjust tuner IF coil to obtain the waveform as A = B

P C warming up the unit for 30 minutes or

during this adjustment. change. Rank "A"
(on right of the CRT)

Green-only Blue-only Red-only

2 RF-AGC 1. Receive "PAL COLOUR BAR" signal. Note: For the 50 ohm signal

TAKE OVER » Signal Strength: 57 ± 1 dBµV (75 ohm open) strength gauge, when not POINT AD2. Connect the oscilloscope to TP201(Tuner�s AGC u s g 0 / 7 5 i m p d a n c e

Signal-colour A

JUSTMENT Terminal) as shown in Fig. 3. adapter, signal strength is
B + TP201 open).

7
» Bias box: About 4.5 V (on left of the CRT) Fig. 3 * Press R/C RGB key for 1 sec-

2

screen cleared (I C BUS 52±1dBµV(75 ohm open), in-

CONTROL) Oscilloscope stead of 57±1dBµV (75 ohm

0.1V Precaution: The loss of using

� impedance adapter A = B Fig. 4-3

Bias box TV Set

+

� Rank "A"

3. Call "AGC" mode in service mode. Adjust the ond in NORMAL MODE, the

"AGC" bus data to obtain the Tuner output pin colour will change to RGB mono drop 0.1V below maximum voltage. colour mode.

4. Change the antenna input signal to 63~67dBµV,

and make sure there is no noise.

5. Turn up the input signal 90~95 dBµV to be sure

that there is no cross modulation beat.

14D1-SA/SF/GA/GF 14D2-SA/SF/GA/GF

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