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8

1. Clean the following parts with a denatured alcohol-moistened

swab :

record/playback/erase head

pinch roller

rubber belts

capstan

idlers

2. Demagnetize the record/playback head with a head demagne-

tizer.

3. Do not use a magnetized screwdriver for the adjustment.
4. After the adjustments, apply suitable locking compound to the

parts adjusted.

5. The adjustments should be performed with the rated power sup-

ply voltage unless otherwise noted.

1. The adjustment should be performed in the publication.

(Be sure to male playback adjustment at first.)

2. The adjustments and measurement should be performed for both

L-CH and R-CH.
• Switch position

DOLBY NR switch

: OFF

DIRECTION MODE switch : g

• Standard record position :

Deliver the standard input signal level to input jack and set the
REC LEVEL  knob to obtain the standard output signal level
as follows.

– Record Mode–

1. While pressing the  H/FRONT (DECK A)  and  REC MUT-

ING W   buttons with the power off, press the  !  button to turn
on the power. The fluorescent display tube lights up for about
one second, and the test mode is set. The test mode performs the
following two special functions.
• Playback speed switching function

Pressing the  HIGH/NORMAL  button switches the playback
speed between standard/double speed.

• Counter RESET & MEMORY function

Resets the counter when recording starts. When rewound with
the  m (AMS)  button after recording, stops at the point where
recording started.

2. To release the test mode, turn OFF the power switch.

Mode

Torque meter

Meter reading

Forward

CQ-102C

30 to 65 g • cm

(0.42 to 0.90 oz • inch)

Forward
back
tension

CQ-102C

DECK A : 1 to 6 g • cm
(0.014 to 0.083 oz • inch)

DECK B : 2 to 9 g • cm

(0.028 to 0.125 oz • inch)

Reverse

CQ-102RC

30 to 65 g • cm

(0.42 to 0.90 oz • inch)

Reverse
back
tension

CQ-102RC

1 to 6 g • cm

(0.014 to 0.083 oz • inch)

FF/REW

CQ-201B

70 to 120 g • cm

(0.97 to 1.67 oz • inch)

Ω

Ω

Ω

Input terminal

LINE IN

source impedance

10 k

Ω

input signal level

0.5 V (–3.8 dBs)

Input terminal

LINE IN

source impedance

10 k

Ω

input signal level

0.5 V (–3.8 dBs)

Tape

Contents

Use

P-4-A100

10 kHz, –10 dB

Azimuth Adjustment

WS-48B

3 kHz, 0 dB

Tape Speed Adjustment

P-4-L300

315 Hz, 0 dB

PB Level Adjustment

9

Procedure:
1. Forward Playback Mode

2. Turn the adjustment screw for the maximum output levels. If

these levels do not match, turn the adjustment screw until both
of output levels match together within 1 dB.

3. Playback Mode

4. Change the reverse playback mode and repeat the steps 1 to 3.
5. After the adjustment, lock the adjustment screws with suitable

locking compound.

Adjustment Location: – record/playback head –

Adjust DECK A first
Procedure:
– Forward Playback Mode –

(High speed adjustment)
1. Press the  PITCH CONTROL  button to set to  OFF .
2. Set to test mode. (Refer to page 11.)
3. Press the  H  button to playback.
4. Press the  HIGH/NORMAL  button to playback at double speed.
5. Adjust RV316 (DECK A), RV416 (DECK B) so that the fre-

quency counter reading becomes 5,980 ± 80 Hz.

(Normal speed adjustment)
6. Press the  H  button to playback.
7. Press the  HIGH/NORMAL  button to playback at normal speed.
8. Adjust RV317 (DECK A), RV417 (DECK B) so that the fre-

quency counter reading becomes 3,000 ± 90 Hz.

(Pitch control adjustment) (DECK A)
9. Press the  PITCH CONTROL  button to set to  ON .
10. Set  PITCH CONTROL  knob to mechanical center.
11. Press the  H  button to playback.
12. Adjust RV318 so that the frequency counter reading becomes

2,990 ± 90 Hz.

Adjustment Location: MAIN board (See page 14.)

W.RMS (JIS) less than 0.3% .
(test tape : WS-48B)

Procedure:
– Forward Playback Mode –

Adjust DECK A : RV111 (L-CH), RV211 (R-CH) and
DECK B : RV121 (L-CH), RV221 (R-CH) so the level meter read-
ing becomes the adjustment limits below.

LINE OUT level : –7.7 dBs ± 0.5 dB (0.301 to 0.338 V)

Level difference between channels : within 0.5 dB

Confirm that the LINE OUT level does not change in playback mode
while changing the mode from playback to stop several times.

Adjustment Location: MAIN board (See page 14.)

Ω

Screen Pattern

Ω

Ω

Ω

Ω

10

This adjustment should be performed when replacing the head assy
or the bias oscillator transformer (T131, T231),(T141, T241).

Setting:
 REC LEVEL  knob : standard recording position (See page 11.)

1. Connect the digital voltmeter to test point TP331 (DECK A) and

TP441 (DECK B).

2. Set DECK A: RV131 (L-CH), RV231 (R-CH) and DECK B:

RV141 (L-CH), RV241 (R-CH) to mechanical center.

3. Press the  H  button to playback.
4. Adjust DECK A: T131 (L-CH), T231 (R-CH) and DECK B:

T141 (L-CH), T241 (R-CH) so that the digital voltmeter r e a d -
ing becomes minimum.

Adjustment Value: Maximum 220 mV

Adjustment Location: MAIN board (See page 14.)

Setting:
 REC LEVEL  knob : standard record position (See page 11.)

Procedure:
1. Set to test mode (See page 11.)
2. Insert a tape into deck B, press the  REC z  button and then

press the  H  button to start recording.

Adjustment level:
The palyback output of 10 kHz level difference against 315 Hz ref-
erence should be ± 0.5 dB.

Adjustment Location: MAIN board (See page 14.)

Setting:
 REC LEVEL  knob : standard record position (See page 11.)

Procedure:
1. Set to test mode (See page 11.)
2. Insert a tspe into deck B, press the  REC z  button and then

press the  H  button to start recording.

3. Record Mode

4. Playback Mode

Ω

Ω

3. Record Mode

Ω

4. Playback Mode
5. Confirm playback the signal recorded in step 2 become adjust-

ment level as follows.
If the selevels do not adjustment level, adjust DECK A: RV131
(L-CH), RV231 (R-CH) and DECK B:  RV141 (L-CH), RV241
(R-CH) to repeat steps 3 and 4.

Ω

Ω

Ω

5. Confirm playback the signal recorded in step 2 become adjust-

ment level as follows.
If the selevels do not adjustment level, adjust the DECK A: RV102
(L-CH), RV202 (R-CH) and DECK B: RV101 (L-CH), RV201
(R-CH) to repeat steps 3 and 4.

LINE OUT level : –23.8 dBs ± 0.5 dB (47.2 to 53.0 mV)

Adjustment Location: MAIN board (See page 14.)

11

Adjustment Location: main board