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Notes:
• Before the adjustment:

Electrical adjustments discussed here are often required after replacement of electronic components and mechanical
parts such as video heads.
Check that the mechanism and all electric components are in good working condition prior to the adjustments,
otherwise adjustments can not be completed.

• Instruments required:

Colour TV monitor
Dual-trace oscilloscope

         Alignment tape (VROCPSV)

Blank video cassette tape
DC voltmeter
Screwdriver for adjustment

Servicing precations
When the IC705 (E

2

PROM) has been replaced, make the following reprogramming. Depending on models, the IC705

(E

2

PROM) has been factory-adjusted for it’s memory function.

It’s therefore necessary to reprogram the memory function for the model in question.
Note that the servo circuit requires readjustments for the head switching point, slow and still modes.

P201

P1551

(TP1551~4)

P811 P812

R4501

AGC

P4501

P4401

R1626

RF AGC

T1601

VCO

Measuring
instrument

Mode

Cassette

Colour TV monitor

Playback

Self-recorded tape
(SP/LP mode) (See Note below)

Control

Tracking control buttons (

'

) or (

"

)

Specification

Minimized noise on
monitor screen

1. Have the unit to receive a good TV broadcast or feed

a video signal to the VIDEO IN jack. (See note 

2

below)

2. Set the tape speed in SP mode by using the remote

control and record the signal on tape.

3. Rewind and play the tape where signal was recorded

in above step.

4. Press the SLOW button on the remote control, and

playback the recorded portion in the slow mode.

5. Make for a moment short-circuit  P812, located at the

front side on the main PWB.
Be sure that all the fluorescent display tubes light up
into the TEST mode.

6. Look at the monitor screen and adjust the (

'

) or (

"

)

TRACKING buttons so that the there is noise disap-
pears from the screen.

7. Press the STOP button to return to normal mode.
8. Play the tape a few seconds then press the SLOW

button again and make sure there is on noise in the
screen. (For the LP mode put adjustment at the same
adjustment way as SP mode.)

1

Self-recorded tape means a cassette whose pro-
gram was recorded by the unit being adjusted.

2

The TV program will not be recorded if RCA or 21pin
plugs are pluged in to the AUDIO/VIDEO input
terminals.

3

The tracking control is enabled with the (

'

)/(

"

)

button.

Measuring
instrument

Mode

Cassette

Dual-trace oscilloscope
Colour TV monitor

Playback

Alignment tape (VROCPSV)

Test point

Pin(2) of P201 (H.SW.P.) to CH-1,
VIDEO OUT jack to CH-2
(CH-1 trigger slope switch at (+),
Internal trigger at CH-1 side.)

Specification

6.5 

±

 0.5H (lines)

1. Remove the front panel and play the alignment tape.

(VROCPSV)
(Playback picture on the monitor screen.)

2. Press the PLAY button.
3. Make for a moment short-circuit P812, located at the

front side on the main PWB.
Be sure that all the fluorescent display tubes light up
into the TEST mode. (See Note below)
Press the PLAY button again.
Be sure the "

û

" appears in the fluorescent display

tubes flashing (about 1Hz) into the auto PG adjust-
ment operating.

When the manual PG adjustment, obseve the wave-
form with an oscilloscope and make adjustment FF or
REW button so that the specification.

4. Stop the "

û

" appears in the flashing of fluorescent

display tubes at adjusted.

5. Make this checking of waveform on the oscilloscope

screen be as shown in Figure 5-2. just after the head
switching point have been adjusted.

6. Press the STOP button in the return to normal mode.
Note:

1

Set-up of TEST mode.
When the adjustment of HEAD SWITCHING POINT,
AUTO TRACKING function is invalid.

2

When the cassette housing control ass’y is removed,
set-up of mechanism operating mode.

1) Replug the AC power cord it a few minutes later.
2) Make a short-circuit P811 located at the front side

on the main PWB, and press both tracking control
button at the same time to set the tracking in
center.

3) AC power cord is plugged in.
4) You can mechanism operating mode, Replug the

AC power cord a few minutes later.

3

The LED lights when the TEST mode is set with the
aid of GAMMA(H).

6.5

±

0.5H (lines)

CH-1: 1V/div 50

µ

s/div

CH-2: 2V/div 50

µ

s/div

V-sync.

CH-1
HEAD
SWITCHING
PULSE

CH-2
VIDEO OUT

Measuring
instrument

Mode

Cassette

Colour TV monitor

Playback

Self-recorded tape
(SP/LP mode)(See Note below)

Control

Tracking control buttons (

'

) or (

"

)

Specification

Minimized noise on
monitor screen

1. Have the unit to receive a good TV broadcast or feed

a video signal to the VIDEO IN jack. (See note 

2

below)

2. Set the tape speed in SP mode by using the remote

control and record the signal on tape.

3. Rewind and play the tape where signal was recorded

in above step.

4. Turn counterclockwise the JOG dial switch of VCR

unit to set the recorded portion reverse Slow play-
back mode.

5. Make for a moment short-circuit  P812, located at the

front side on the main PWB.
Be sure that all the fluorescent display tubes light up
into the TEST mode.

6. Look at the monitor screen and adjust the (

'

) or (

"

)

TRACKING buttons so that so as to get minimum
noise on the screen.

7. Press the STOP button to return to normal mode.
8. Play the tape a few seconds then turn counterclockwise

the JOG dial switch to set the reverse Slow playback
mode (Check the noise on the screen.), and make
sure there is on noise in the screen. (For the LP mode
put adjustment at the same adjustment way as SP
mode.)

1

Self-recorded tape means a cassette whose pro-
gram was recorded by the unit being adjusted.

2

The TV program will not be recorded if RCA or 21pin
plugs are pluged in to the AUDIO/VIDEO input
terminals.

3

The tracking control is enabled with the CH(

'

)/(

"

)

button.

Measuring
instrument

Mode

Cassette

Colour TV monitor

Playback still

Self-recorded tape (SP mode)
(See Note below 

2

)

Control

Tracking control buttons (

'

) or (

"

)

Specification

No vertical jitter of picture

1. Play a cassette which was recorded by the unit in SP

mode.

2. Press the PAUSE/STILL button to freeze the picture.
3. Look at the monitor screen and adjust (

'

) or (

"

)

TRACKING buttons so that the vertical jitter of the
picture to be minimized.

4. Play and freeze the self-recorded tape in SP mode

and make sure vertical jitter of the picture is not
noticeable. (For the LP mode put adjustment at the
same adjustment way as SP mode.)

1

The FV goes back to the it’s initial state when the unit
is put into the system controller reset mode due to
power failure, etc.
In this case, preset the FV once again.

2

Self-recorded tape is a cassette whose program was
recorded by the unit being adjusted.

3

The tracking control is enabled with the (

'

)/(

"

)

button.

Measuring
instrument

Mode

Test point

Colour TV monitor
DV voltmeter

RF signal at 12CH (by VHF
signal generator)

Pin(2)(Sig.) of TP1552
Pin(4)(GND.) of TP1554

R1626 RF AGC control

4.3 

±

 0.2V

1. Receive the 12 channel signal (colour bar signal at

87.5% modulated.) at input field strength: 59dB

µ

 of

antenna terminal.

2. Connect a DC voltmeter to test point shown in table.
3. Look the voltmeter and adjust R1626 so that the

voltage be specified.

Control

Specification

Measuring
instrument

Mode

Test point

Colour TV monitor
DV voltmeter

Control

T1601 VCO control

Specification

2.5 

±

 0.2V

RF signal at 12CH (by VHF
signal generator)

Pin(1)(Sig.) of TP1551
Pin(4)(GND.) of TP1554

When power is turned on, tune in to station in the
TEST mode.

1. Receive the 12 channel signal (colour bar signal at

87.5% modulated.) at input field strength: 70dB

µ

 of

antenna terminal.

2. Connect a DC voltmeter to test point shown in table.
3. Look the voltmeter and adjust T1601 so that the

voltage be specified.

Measuring
instrument

Mode

Test point

Colour TV monitor
Dual-trace oscilloscope

Colour-Bar video signal at S-
Terminal (by video signal generator)

Pin(2)(input Sig.) of P4501
Pin(1)(output Sig.) of P4501
Pin(3)(GND.) of P4501

Control

R4501 AGC control

Specification

2.0 

±

 0.1V

1. Receive the video signal in the state of input selection

CH : L3.

2. Connect the oscilloscope to the test point shown in

the table.

3. Make sure that the input signal level (about 1Vp-p) of

pin(2) of P4501 exists.

4. Make an adjustment with R4501, seeing the oscillo-

scope, so that the output signal of pin(1) of P4501
conforms to the specification.

Specification

Measuring
instrument

Colour TV monitor
DC voltmeter
Dual-trace oscilloscope

Mode

Colour-Bar video signal at S-
Terminal (by video signal generator)

Pin(3) of P4401 (GAMMA slice level adjustment point)
Pin(1) of P4401 (GAMMA level adjustment point)
Pin(4) of P4401 (GAMMA sync level adjustment point)
Pin(2) of P4401 (GAMMA video output level adjustment point)
Pin(5) (GND.), Pin(6) (E-E Sig.) of P4401

Control

Display indication
0 : 00 : 00  01

00

Press the DAC key
Set mode

Selection with 
GAMMA key

Pin(1) 
Control

Adjustment data 
(8-bit hex indication) 
(Control with (

'

) (

"

) 

button of unit or  (

'

) 

(

"

) button of remote 

control transmitter)

A1 : GAMMA AUTO
1 1 : GAMMA MODE1
2 1 : GAMMA MODE2
3 1 : GAMMA MODE3
_ 3 : Pin(3) Control
_ 4 : Pin(4) Control
_ 2 : Pin(2) Control

D

A1

Indication of DAC setting

Selection with 
remote control 
CH key

Test point

Pin(3) : 1.80 

±

 0.05 V DC

Pin(1) : GAMMA AUTO

: 0 

±

 0.1V DC

Pin(1) : GAMMA MODE1 : 1.35 

±

 0.05V DC

Pin(1) : GAMMA MODE2 : 2.55 

±

 0.05V DC

Pin(1) : GAMMA MODE3 : 4.15 

±

 0.05V DC

Pin(4) : 1.37 

±

 0.03V DC

Pin(2) : The same level (Vp-p) as that of pin(6)

1. Remove the front panel.
2. Receive the video signal in the state of input selection

CH : L3.

3. Touch-short-circuit the pins(1) and (2) of test pin

P812 provided at the front side of main PWB. When
the GAMMA LED lights, at the same time the display
tube lights wholly (instantaneously).

4. Press simultaneously the GAMMA button and SET

button to set the DAC setting mode.

5. Connect the DC voltmeter to the pin(3). Press the

remote control CH key"3". The indication D_3_00
appears.
Change the control data with the (

'

)/(

"

) button, and

make an adjustment so as to ensure conformity to the
specification.

6. Connect the DC voltmeter to the pin(1). Press the

remote control CH key"1".

a) GAMMA AUTO mode indication

D_A1_00

Make an adjustment so as to ensure the conformity to
the specification with the (

'

)/(

"

) button.

b) Press the GAMMA button.

Mode 1 indication

D_11_00

Make an adjustment so as to ensure the conformity to
the specification with the (

'

)/(

"

) button.

c) Press the GAMMA button.

Mode 2 indication

D_21_00

Make an adjustment so as to ensure the conformity to
the specification with the (

'

)/(

"

) button.

d) Press the GAMMA button.

Mode 3 indication

D_31_00

Make an adjustment so as to ensure the conformity to
the specification with the (

'

)/(

"

) button.

7. Connect the DC voltmeter to the pin(4). Press the

remote control CH key"4".

The indication

D_4_00

Make an adjustment so as to ensure the conformity to
the specification with the (

'

)/(

"

) button.

8. Connect the oscilloscope to the pins(2) and (6). Press

the remote control CH key"2".

The indication

D_2_00

Make an adjustment so as to get the pin(2) signal level
equal to that of pin(6), using the (

'

)/(

"

) button.

9. Cancel the setting mode with SET button (the Digitron

display gives the ordinary indication).

Note:
1. Replug the AC cord it a few minutes later.
2. (

'

)/(

"

) shows the (

'

)/(

"

) button of the unit or the

(

'

)/(

"

) button within the door of remote control trans-

mitter.