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Notes:
• Before the adjustment:

Electrical adjustments discussed here are often required after replacement of electronic components and mechani-
cal 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:

Blank video cassette tape
DC voltmeter
Screwdriver for adjustment

Colour TV monitor
Dual-trace oscilloscope

         Alignment tape (VROCBZF)

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 factry-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.

Measuring
instrument

Mode

Cassette

Oscilloscope

Playback

Aligment Tape (VROCBZF)

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. PB the self-REC tape.
2. Set to SLOW PB mode by pressing the SLOW key.
3. Transmit the TEST(R/C code 47H).Or short the P802

on the main PWB once.

4. Adjust the noise bar at the botton of monitor screen

using TRACKING UP,DOWN key until it dissapear.

5. Press the PB key to PB and during this time, press the

PB/STILL for few times repeatedly and during STILL
make sure no noise appear.
same with the SP, do the 1~5 items.(for LP and EP)

~

. For LP, skew will appear at the above.

For EP, noise appear at the above and bottom.
Adjust this noise to be almost same for the both side.

Measuring
instrument

Mode

Cassette

Monitor Screen

Playback

Self-recorded tape
(SP/LP/EP mode)

Control

Tracking control buttons (

]

) or (

[

)

Specification

Minimized noise on
monitor screen

1. Insert the Aligment Tape and (VRO-CBZF) set to PB Mode.
2. Transmit the TEST code (R/C code 47H) to VCR.

Or, once, short the P802 at the main PWB
(By doing this,LCD will all light up and become the PB
Tracking Center value.

~

As for the recover equipment,prepare the memory-remote
control.
But,while adjust the running, at non cassete control unit
condition but have the cassete control JP(P802 short on the
main PWB), if press TRACKING UP and DOWN key at the
same time, it'll become the TRACKING  CENTER (for
Running Ajustment)

3. Again, transmit the PLAY (PB), or Press PLAY Key.After

AUTO PG ADJ mode is finished, make sure the PB Switch-
ing Point is inside standard range.

~

During Flashing of PLAY(casette mark) is AUTO PG ADJ,
finish the AUTO PG ADJ,by light off.

~

When using the manual PG ADJ,finish the No.2, and it is
able to adjust the PG using FF key or REW key.

Measuring
instrument

Mode

Cassette

Monitor Screen

Playback still

Self-recorded tape
(SP/LP/EP mode)

Control

Tracking control buttons (

]

) or (

[

)

Specification

No vertical jitter of picture

1. PB the self-REC tape.
2. Press the PAUSE/STILL key and STILL the picture.
3. As looking at the monitor, using the TRACKING UP+,

DOWN

−

 adjust till the perpendicular jitter dissapear.

~

For the LP also, while PB the self-REC tape, for STILL,
it is better to confirm that no perpendicular jitter appear.

CH-2

Video output

CH-1

V: 2V/div

V: 1V/div

TRIG INT CH-1,H:50 

µ

sec/div

6.5H

Observe the video output using the oscilloscope and confirm as
the above diagram

*

V:200mV/div
H:20

µ

 sec/div

Measuring
instrument

Mode

Cassette

Spectrum
Analyzer

Recorded

Self-recorded tape

Test point

YC CHIP Pin98

Specification

3.8MHz

±

50KHz

VIDEO

PAL Colour Bar(1Vp-p)

Measuring
instrument

Mode

Cassette

Oscilloscope

Recorded

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

Test point

VIDEO OUT 21PIN or RCA Port
(75

Ω

 Terminal)

Specification

1.0

±

0.2Vp-p

VIDEO

PAL Colour Bar(1Vp-p)

Measuring
instrument

Mode

Cassette

Spectrum
Analyzer

Recorded

Self-recorded tape

Test point

YC CHIP Pin98

Specification

4.8MHz

±

100KHz

VIDEO

Colour Bar(1Vp-p)

3.80

4.80MHz

A

f

<Deviation>
Confirm the white peak frequency follow
the standard value.
(the deviation between shinkchip and f
white peak is 1MHz

±

100KHz)

Measuring
instrument

Mode

Cassette

Oscilloscope

Self-recorded/Playback tape

Test point

YC CHIP Pin98

Specification

about300mVp-p

VIDEO

Colour Bar(1Vp-p)

<Diagram A>

Confirm the Sink chip is as the
left diagram <Diagram A>.

1.0Vp-p

Sink Chip

Recorded

Measuring
instrument

Mode

Cassette

Oscilloscope

Playback

Self-recorded/Playback tape

Test point

VIDEO OUT port
(75

Ω

 terminal)

Specification

Check place 1.
(1

±

0.2Vp-p)

VIDEO

Colour Bar

1.0Vp-p

Measure the picture out-
put port using the 75

Ω

 ter-

minal Oscilloscope and
confirm the diagram same
as the left diagram.

~

V:200mV/div
H:20

µ

sec/div

Measuring
instrument

Mode

Cassette

Oscilloscope

Recorded/Playback

Self-recorded/Playback tape

Test point

VIDEO OUT

VIDEO

mono-sco

Receive the mono-sco.
Confirmation : make sure no black split at the mono-sco
picture during the self-Rec PB when the S-PICTURE is
ON with the S-PICTURE ON/OFF,make sure the picture
level at the wedge part is change.

(S-PICTURE ON - about 260 line)
(S-PICTURE OFF about 240 line)

Measuring
instrument

Mode

Cassette

Voltmeter

EE

Optional

Test point

AUDIO OUT

Specification

-3.8

±

2dBs

VIDEO

Optional

AUDIO

AUDIO IN at 1KHz -3.8dBs

Measuring
instrument

Mode

Cassette

Voltmeter

Playback

Alignment Tape VRO-CBFF

Test point

AUDIO OUT

Specification

-3.8

±

2dBs

VIDEO

Optional

AUDIO

Optional

Measuring
instrument

Mode

Cassette

Voltmeter

Recorded/Playback

Self-recorded tape

Test point

AUDIO OUT

Specification

-3.8

±

2dBs

VIDEO

Optional

AUDIO

AUDIO IN at 1KHz -3.8dBs

~

For this item, variable the tracking switch, and confirm
the changing of the normal mode.