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– 5 –

claw

1. Remove the battery cover 

8

.

2. Push two claws with a screwdriver or equivalent on the bottom and

remove them.

3. While pushing the rear cabinet, remove claws of joints with

the front cabinet.

4. Insert a screwdriver or equivalent to the gap on the upper side of the

cabinet, and while pushing the lock spring, put it down to the rear cabinet
side.

5. Remove the channel button 

2

.

6. Disconnect CN501 (for  speaker) on the A board.
7. Remove the B board 

3

 and the A board 

4

.

8. Remove solder for the lead wire (BLK) 

9

.

9. Remove a screw (+PTP2X6) 

6

 secured the T board 

5

.

10. Release the T1 board 

5

 from two claws (right and left) on the rear cabinet.

front cabinet

rear cabinet

lock spring

8

battery cover

2

channel button

7

rear cabinet

claw

1

front cabinet

3

B board

5

T1 board

6

screw (+PTP2X6)

4

A board

9

lead wire (BLK)

– 6 –

CN301

Mini-jack

J101

CN201

T1 board

B board

Cable for service
1-900-211-84

CN601

A board

CN602

Cable for service
1-900-211-84

AC power adaptor

Antenna

– 7 –

Using a digital voltmeter measuring the voltage between
JL32 (+4.5V) and JL33 (GND). Adjust RV601 to obtain
the value shown below.

±

Check the voltage across JL29 (+30.0V) and JL33 (GND) .

±

1.  Feed the audio signal 1kHz 100% modulated.
2.  Set RV501 to maximum.
3.  Connect an oscilloscope between JL23 (SP) and JL15 (SP

GND).

4.  Check the waveform on the oscilloscope becomes the stan-

dard value.

[

SETUP

]

1. Set S601 on the A board to VHF position.
2. Apply no signal to JL18 (RF).
3. Connect a 1 k

Ω

 resistor between JL77 (+4.5V) and

    JL28 (RF AGC).
4. Apply a sweep signal across JL26 (IF) and JL27(IF GND).

(Fig. 3-1)

Note

 : Set the sweep signal for JL26 to -30

±

5dBm. Keep the

distance to the ATT output  JL26 as short as possible.

[ADJUSTMNT]
1. Connect an oscilloscope between JL72  (VIDEO) and JL71

(A.GND) and apply an external     voltage (MGC) to JL26 to
obtain a waveform as shown in Fig. 3-2 (make sure not to
clip the extremely short portion).Adjust T202 so that the po-
sition at 45.75 MHz is the lowest point.

Note

 : Align JL51 (MGC) external voltage for approximately

       a 1.0 Vp-p. Make sure that the JL51 (MGC) external
       voltage does not exceed 4.3VDC.
2. Remove the external voltage (MGC) from JL51.
3. Connect an oscilloscope between JL31 (AFT) and JL30

(D.GND) and make a coarse adjustment of T201 so that wave-
form is close to zero at the 45.75 MHz position.

4. Remove the 1 kilohm resistor connected between JL77 (+4.5V)

and JL28 (RF AGC).

JL26

75

Ω

 6dB

fo=45.75MHz

±

5kHz

SWEEP
MARKER
GENERATOR

0.01

µ

F

ATT

1Vp-p

45.75MHz

0

TU101

RV201

T201 T202

RV002

RV004

RV001

- T1 board - (Component side)

– 8 –

1. Receive the color bar signal from the signal generator.
2. Observe the waveform across JL81(B) and JL67(D.GND).
3. Adjust RV301 (TINT) so that the waveform level becomes as

shown in Fig. 3-6.

1. Receive the stepped waveform signal in 10 steps.
2. Observe the waveform across JL83(G) and JL67(GND).
3.  Check the contrast changes by turning RV402.
4.  Connect an oscilloscope between JL84 (AUTO CB) and JL67

(D. GND) and adjust RV402 so that the voltage of A portion
becomes 2.2+-0.2V.

5.  Check the waveform as shown in Fig. 3-5.
6.  At the same time, check the points C and D are within the

period as shown in Fig. 3-5.

1. Set S601 to VHF position and receive a VHF color bar signal

issued from a signal generator.

2. Adjust RV201 and align the screen for the optimal point so

that the snow noise disappears.

1. Set S601 to VHF position, a potentiometer (47k

Ω±

15k

Ω

)

across JL25(CS) and JL77 (+4.5 V) as shown in Fig. 2-6 and
short the points JL21(CH CAL) and JL30 (D.GND).

2. Receive channel 2 and align the channel display positions with

RV002(VP).

3. Receive channel 13 and align the display bar with RV004(VA).
4. Align while performing tracking to mutual interference in the

above steps 2 and 3.

5. Receive channels 3 & 4 and confirm that the display bar is

within the standards.

6. Set S601 to UHF.
7. Receive channel 14 and align the display position with

RV001(UP).

8. Receive channel 69 and confirm that the display bar is within

the standards.
Once again receive channel 14 and confirm that the display
bar is within the standards.

  Note

 : Use caution since shifting channel 69 will also

              cause channel 14 to shift.
9. Remove the potentiometer (47k

Ω

+15k

Ω

) you connected be-

tween JL25(CS) and JL77(+4.5V). Also remove the short you
connected between points JL21 (CH CAL)and JL30(D.GND).

1. Connect a 1 kilohm resistor between JL77 (+4.5V) and JL28

(RF AGC).

   Note

 : Perform this adjustment as the last step in the

               process   since drift may occur due to aging.
2. Switch the sweep signal to CW.

             fo= 45.75 MHz

±

5 kHz, -30

±

5dBm

     Apply the above signal between JL26 (IF) and JL27 (IF GND)
    and then make a fine adjustment of T201 so that the level be-

tween JL31 (AFT) and JL30 (D.GND) reaches2.2V

±

0.4VDC.

3. Remove the 1 kilohm resistor connected between JL77 (+4.5V)

and JL28 (RF AGC).

JL83

JL84

0 IRE

100 IRE

C

D

A=2.2

±

0.2VDC

Contrast changes

Display bar

Channel No.

*Channel No. and display
bar are to be in line.

RV402

RV301

- B board -
(Component side)

JL25 (CS)

JL77(+4.5V)

15k

Ω

VR(47k

Ω

)