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AC Head 
FFC
Holder

• Replacement
1. Solder the removed PWB to the new head assembly.
2. Adjust the height from the A/C head plate (lower surface)

to the A/C head base to 10.8mm with slide calipers. (3
places of azimuth screw section, tilt screw section and A/
C head front section) (See the figure below.)

1. In eject position unplug the power cord.

• Removal
1. Take out FFC holder from main chassis.

(Push 3 hooking point and pull-up the
holder).

2. Remove the screws 123, Tilt screw.
3. Unsolder the PWB fitted to the A/C head.

Notes:
1. When replacing, never touch the head. If you touched,

clean with the cleaning liquid.

2. When removing the screw 3, take care so that the

spring may out.

3

1

2

A/C head screw

Azimuth spring

Height adj. screw

A/C head base
(with A/E)

Tilt screw

Height Adj. spring

A/C head PWB

Azimuth adj. screw

*Direction designation.
(The bottom part is big.)

A/C head plate

10.8mm

A/C head FFC

A/C FFC holder

Solder

A/C head PWB

New A/C head ass'y

A/C head base

*Fit the groove of FFC to
 the boss of the holder.

A/C head base

A/C head plate

3. Align the left end of gear of A/C head plate with the

punched mark of chassis, tentatively tighten the screws
1 so as to ensure smooth motion of A/C head plate.
Tentative tightening torque must be 0.45 

± 0.05N·m (4.5

± 0.5kgf·cm) and final tightening torque must be 0.6N·m
(6kgf·cm).

Notes:
1. If the screw 1 is tighten tentatively too loose, the

azimuth and height of A/C head may change when they
are finally tightened. Therefore care must be taken.

2. After completion of A/C head be sure to adjust tape

running. (Execute the running adjustment by the method
described in 8-19.)

Height screw

Left end of A/C head plate gear
Punched line mark on chassis

1

1. Set the cassette tape in the unit.
2. Press the PLAY button to put the unit in the playback

mode.

3. Roughly adjust the height of the A/C head by turning the

height screw until the tape is in the position shown
below.

Tape

0.3mm

A/C head

• Adjustment
Adjust the height screw

 

visually so that the control head is

visible 0.3 mm below the bottom of the tape.

Mechanism chassis

Cassette tape

Height screw

Tilt screw

Azimuth screw

Cassette Tape

1. Tape run rough adjustment

1 Check and adjust the position of the tension pole.

(See 8-14.)

2 Check and adjust the video search rewind back

tension. (See 8-12.)

3 Connect the oscilloscope to the test point for ATR

signal output (TP201). Set the synchronism of the
oscilloscope to EXT. The PB CHROMA ATR signal
is to be triggered by the head switching pulse (TP202).

4 Set the alignment tape (VROCPSV) to play.

5 Press the tracking button (+), (–) and change the

ATR signal waveform from max to min and from min
to max. At this time make sure that the ATR signal
waveform changes nearly parallel.

6 Unless the ATR signal waveform changes nearly

parallel, adjust the height of supply side and take-up
side guide roller so that the envelope waveform
changes nearly parallel. (For ATR signal adjustment
procedure refer to Figure 8-31.)

7 Turn the tilt screw to remove the tape crease at the

fixing guide flange.
Playback the tape and check for tape crease at the
fixing guide flange.
(1) If there is no tape crease

Turn the tilt screw clockwise so that tape crease
appears once at the flange, and then return the tilt
screw so that the crease disappears.

(2) If there is tape crease

Turn counterclockwise the tilt screw so that the
tape crease disappears.
(Reference) If the tilt screw is turned clockwise
crease appears at the lower flange.

Guide roller

Notes:
1. Previously set the tracking control in the center position,

and adjust the ATR signal waveform to maximum with X
value adjustment nut. Thereby the tape run rough ad-
justment is facilitated.

2. Especially the outlet side ATR signal waveform must

have higher flatness.

2. Adjustment of A/C head height and azimuth

1 Perform the initial setting of A/C head position by the

method stated in "8-17 Replacement 3".

2 Connect the oscilloscope to the audio output terminal.
3 Using the alignment tape in which 1 kHz linear audio

signal has been recorded, adjust the height screw so
as to get max audio output.

4 Using the alignment tape in which 7 kHz linear audio

signal has been recorded, adjust the azimuth screw
so as to get max audio output.

5 The adjustment of 3 and 4 twice or three times

repeat, and finally adjust 4.

For X value adjustment
Adjust the X value, turning the gear-
type screwdriver.

3. Tape run adjustment

1 Connect the oscilloscope to PB CHROMA ATR

signal output test point, set oscilloscope sync to
EXT, trigger-input the PB CHROMA signal (head
switching pulse).

2 Rough adjustment of X value

Tentatively fix A/C head arm screws 1  by the method
described in "8-17 Replacement 3".
Playback the alignment tape (VROCPSV) and
shortcircuit between TP803 and TP802 on VCR
Operation PWB. As a result the auto-tracking is
automatically cancelled, so that the X value adjust-
ment mode is set.
Move the A/C head with the X value adjustment gear
driver (JiGDRiVER-6) by the method shown in Fig-
ure 8-34, and adjust the A/C head so as to get the
maximum ATR signal waveform. (Note: When the A/
C head is adjusted, adjust so that the maximum ATR
signal waveform is obtained nearest the position of
initial setting made in 8-17.)

3 Next, press the tracking button (+), (–) and change

the ATR signal waveform from max to min and from
min to max. At this time adjust the height of supply
and take-up side guide roller with the adjustment
driver (JiGDRiVERH-4) so that the ATR signal wave-
form changes nearly parallel.

4 If the tape is lifted or sunk from the helical lead

surface, the PB CHROMA ATR signal waveform
appears as shown in Figure 8-31.

5 Press the tracking button (+), (–) and make sure that

the ATR signal waveform changes nearly parallel.

6 Finally, check tape crease near the reverse guide. If

tape crease is found, adjust tilt screw 45˚ counter
clockwise. Small tape crcase will appear at retain
guide after this adjustment finished.

PB CHROMA
ATR Signal

Notes:
When the A/C head X value adjustment is performed, be
sure to perform at first X value rough adjustment (refer to 8-
19, 3-2).

4. A/C head X value adjustment

1 Fix A/C head arm screws 1 and 2 tentatively by the

method described in "8-17 Replacement 3".

2 Playback the alignment tape (VROCPSV), and

shortcircuit between TP803 and TP802 on VCR
Operatin PWB. As a result the auto-tracking is auto-
matically cancelled, so that the X value adjustment
mode is set.

3 Move the A/C head with the X value adjustment gear

driver by the method shown in Figure 8-34, and
adjust the A/C head so as to get the maximum ATR
signal waveform. (Note: At this time adjust so as to
get the maximum ATR signal waveform nearest the
A/C head position which has been set in case of X
value rough adjustment as stated in 8-19, 3-2.)

4 Adjust the playback switching point (Refer to the

electric adjustment method.)

5 Playback the self-picture-recorded tape, and check

the flatness of ATR signal waveform and sound.

1

Take-up side

Supply side

Take-up side

Adjustment

Supply side

Supply side guide roller
rotated in clockwise
direction (lowers guide
roller) to flatten
ATR signal.

Take-up side guide roller
rotated in clockwise
direction (lowers guide
roller) to flatten
ATR signal.

Supply side guide roller
rotated in counterclock-
wise direction (raises
guide roller) to make the
tape float above the helical
lead. The supply
side guide roller is then
rotated in the clockwise
direction to flatten the
ATR signal.

Take-up side guide roller
rotated in counterclock-
wise direction (raises
guide roller) to make the
tape float above the
helical lead. The take-up
side guide roller is then
rotated in the clockwise
direction to flatten the
ATR signal.

When the tape is below the helical lead.

When the tape is above the helical lead.