Sharp SX80J9 Service Manual Download

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SX80J9

1. PIP Y LEVEL ADJUSTMENT:

R4938 (on P-in-P unit)

1. Receive E-12CH "PAL COLOUR BAR" signal for

the main and PIP.

2. Connect the oscilloscope to TP805(PI (16)) on

the main unit.

3. Adjust R4938 so that the 100% white portion in

the PIP and that in the main screen be at the
same level. (See

Fig.5.)

• Adjustment error: 0 ± 0.02 V.

Note: The level difference between the pedestal and

that 100% white portion should be 0.7Vp-p or
so.

2. PIP SUB-COLOUR ADJUSTMENT:

R4952 (on P-in-P)

1. Receive E-12CH "PAL colour bar" signal for the

main and PIP.

2. Connect the oscilloscope to TP804 (PI(14)) on

the main unit.

3. Adjust R4952 so that the R-Y red portion in the

PIP and that in the main screen be at the same
level.(See

Fig.6.)

PIF/AFT/AGC ADJUSTMENT

DC voltage at TP201 [ Pin (1) of IC201]

3.3V

DOWN A B' B B'' C UP

TP101 [ Pin (1) of IC101]

DIGITAL COMB FILTER Y LEVEL ADJUSTMENT

1. DIGITAL COMB FILTER Y LEVEL ADJUSTMENT: R5467

1. Input the PAL colour bar (100% white colour bar) signal to AV-IN terminal with a 75 ohm termination (input

level 1.0 Vp-p ± 0.05Vp-p).

2. Connect the oscilloscope to TP5462 (connector YA pin (7)).
3. Adjust R5467 so that the Y signal (100% white) at TP5462 be 2.0 ± 0.1Vp-p.

Note: Make sure that the signal is linearly amplified overall. (The 100% portion should be kept intact.)

<Reference> Note the voltage level for the adjustment with the E-12CH signal.
To be adjusted to 2.0 Vp-p at TP5462
* Make sure the above value is available after the adjustment No. 5. (See Page 12.)
Input (YB) (2):

2.0 V ± 0.1 Vp-p

Output (YA) (7):

2.0 V ± 0.1 Vp-p

PIP (SUB-SCREEN) ADJUSTMENT

3. AFT ADJUSTMENT: T204(T104)

1. Receive the E-12CH (PAL colour bar) signal. If

this signal is not available, any signal above the
E-5CH band is acceptable.
•Field strength:

55~80 dBµV

Make sure the frequency is almost the same as
that of the received channel (± 30 kHz).

2. Using the channel setting control, make a fre-

quency of 224.25 MHz appear on the screen.
(AFT off)(If any other channel than E-12CH is
received, make its frequency on the screen.)

3. Turn T204 (T104) coil clockwise first to have 6V

reading and then counterclockwise to get 0.2 V
reading.
Within this range, adjust this coil to reach the volt-
age below.

4. Adjust T204 (T104) so that the DC voltage at the

pin (1) of IC201 (IC101) be 3.3 ± 0.2 V. (See

Fig.

3.)

Note: Operate PIP when you adjust T104.

4. RF AGC CUT-IN ADJUSTMENT: R226 (R116)

1. Receive the E-12CH "PAL COLOUR BAR" signal.

• Field strength: 57 ± 1 dBµV (75 ohms open)

2. Connect the oscilloscope to P201 (P101), as

shown in

Fig. 4.

• Bias box: About 6.5V

3. Turn R226 (R116) to have the highest voltage.
4. Turn R226 (R116) slowly in the oppsite direction

untill the voltage goes down 0.1V below the high-
est level.

5. Adjust the signal level to 63-67 dBµV and make

sure there are no noise.

6. Now adjust the signal level to 90-95 dBµV and

make sure there is no chrominance modulation
beat.

Note: Operate PIP when you adjust R116.
Note: If a 50 ohm field strength meter is used with-

out a 50/75 impedance converter, set the field
strength to 55 ± 1dBµV. Pay attention to a loss
that would be cause with the converter.

5. VIDEO DETECTION LEVEL ADJUSTMENT: R224

1. Receive the "B/G SYSTEM PAL COLOUR BAR" signal (100% white colour bar). Set the S system to B/G.
2. Adjust R224 so that the video output at the AV OUT terminal be 1.0 ± 0.05 Vp-p with a 75-ohm termination.

Oscilloscope

TV Set

0.1V

Bias box

P201
(P101)

* Turn the core counterclockwise for the UP di-

rection, and clockwise for the DOWN direc-
tion. Adjust the T204 core to point B (between
B' and B''). Point A and C are rejectable.

Fig. 3

Fig. 4

H: Horizontal sync
V: 0.1 V/div. (reading)

Fig. 5

H: Horizontal sync
V: 0.1 V/div. (reading)