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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)

2. Press the PLAY button.

(Playback picture on the monitor screen.)

3. Make for a moment short-circuit P802, 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)
Be sure the "PLAY" 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 "PLAY" appears in the flashing of fluorescent

display tubes at adjusted.

5. Press the STOP button in the return to normal mode.
6. 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.

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 P801 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 operatig mode, Replug the AC

power cord a few minutes later.

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-ciucuit  P802, 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
adjustmet 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.

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

Test point

Colour TV monitor
DV voltmeter

RF signal at 40CH(by VHF
signal generator)

Pin(2)(Sig.) of P1501.
Pin(4)(GND.) of P1501.

Control

R1626 RF AGC control

Specification

3.9 

±

 0.2V

1.Receive the 40 channel signal (colour bar signal at
   87.5% modulated.) at input field strength: 56dB

µ

 of

   antenna terminal.
2.Connect a DC voltmeter to test point shown in table.
3.Look the voltmerter and adjust R1626 so that the
   voltage be specified.

Measuring
instrument

Mode

Test point

Colour TV monitor
DV voltmeter

Control

T1601 VCO control

Specification

2.5

±

0.2V

RF signal at 40CH(by VHF
signal generator)

Pin(1)(Sig.) of P1501.
Pin(4)(GND.) of P1501.

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

1.Receive the 40 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 voltmerter and adjust T1601 so that the
   voltage be specified.

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.

1

0

1

1

 

1

10

1

1

1

1

1

0

1

0

0

0

1

0

1

0

0

0

1

0

0

0

0

0

1

0

0

0

1

0

1

0

0

0

1

0

S sensor

Open

Close

Mode detection inside

sensor A

1

1

1

0

0

0

0

0

0

Mode detection inside

sensor B

0

1

1

1

1

0

1

1

0

CS/EJ

ULD

PU1

PU2

VSR

PB

SLOW

FF

STOP

Cam graph E

25

20

15

10

5

0

60

120

180

240

300

360

G mechanical timing

Mode check

Cam mark 

Mode detection outside

(D709 SW B)

Mode detection inside

(D708 SW A)

0

19.812

81

179

233

200

265

282

316

334

10.354

12.812

CA/END

CS/EJ

UL

PU1

PU2

VSR

PB

SLOW

FF

STOP

Mode detection outside

Mode detection inside

S sensor

EJ

UL

PU

PU2

VSR

PB

SLW

FF

STP

0

1

1

0

1

1

0

0

0

0

0

1

0

0

1 or 0

Loading motor turns in reverse

direction and master cam

counterclockwise.

Cassette

inserting

Full-

loading

Unloading

Loading motor starts in normal

direction and master cam counter

clockwise.

Does mechanism position sw.

come off within 2.5 sec.?

Are start/end sensors at low level

before cassette insertion ?

Insert cassette.

Double action rack slides.

Drum motor starts.

Tape loading.

Pinch roller comes into contact.

Cam switch is at PB position.

Loading motor stop.

Is drum FG pulse outputted ?

End

End

Cassette is ejected and loading

motor stops.

Start sensor close.

(Cassette is judged

caught halfway.)

(Cassette LED or some other part

is judged defective.)

Capstan motor turns

counterclockwise.

Is take-up reel sensor signal

outputted ?

End

Press REC/PLAY key.

Picture appears.

Unloading

Set capstan motor to search

speed.

End

Press FF key.

Capstan motor turns in

reverse direction.

Loading motor turns in

counterclockwise direction

and master cam clockwise.

Slow brake comes into

contact with capstan motor.

Slow brake

pressing

Cam switch is at STILL

position.

End

Capstan motor stops.

Press STOP key.

Loading motor stops.

End

Stop capstan motor.

Press STILL key.

Pinch

roller

releasing

Idler

swinging

Pinch

roller

pressing

Loading motor turns

clockwise and master

cam counterclockwise.

Turn capstan motor in

reverse direction.

Turn loading motor

counterclockwise.

Cam switch is at VSR

position.

Set capstan motor to search

speed.

Is take-up reel sensor signal

outputted ?

Press REW key.

Release pinch roller.

Cam switch is at PU2 position.

Cam switch is at PU1 position.

Stop loading motor.

Press pinch roller.

Loading motor turns clockwise.

Release the supply auxiliary 

brake.

Stop loading motor.

End

Unloading

Cam switch is at PB position.

End

Press PLAY Key.

Loading motor turns counter-

clockwise and master cam

clockwise.

Capstan motor turns

counterclockwise. PB speed.