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– 9 –

2

 BVTT 2x3

1

 torsion spring

5

 reverse slider

4

 mechanical block assy

3

 BVTT 2x3

3

 tension spring (HEAD)

2

 HEAD RELAY (PB) board

     (Deck A)
    HEAD RELAY (REC) board
    (Deck B)

1

 BVTT 2x4

4

 head deck assy

– 10 –

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

demagnetizer.

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

supply voltage unless otherwise noted.

Forward

CQ-102C

30 to 65 g • cm

(0.42 to 0.90 oz • inch)

DECK A : 1 to 6 g • cm

Forward

(0.014 to 0.083 oz • inch)

back

CQ-102C

tension

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

1 to 6 g • cm

back

CQ-102RC

(0.014 to 0.083 oz • inch)

tension

FF/REW

CQ-201B

70 to 120 g • cm

(0.97 to 1.67 oz • inch)

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 : 

A

• Standard record position :

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

– Record Mode–

source impedance

10 k

Ω

input signal level

0.5 V (–3.8 dB)

load impedance

47 k

Ω

output signal level

0.5 V (–3.8 dB)

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

set

AF OSC

attenuator

10 k

Ω

600 

Ω

LINE IN

level meter

LINE OUT

47 k

Ω

1. Turn ON power switch pressing “REC MUTING” and “

)”

(FF) (DECK A) at the same time.
At first, all the fluorescent indicator light up, then the system
returns to normal display. (However, “0. 00” is not displayed on
the counter.)

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

– 11 –

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–

set

test tape
P-4-A100
(10 kHz, –10 dB)

level meter

LINE OUT

47 k

Ω

within
1 dB

within
1 dB

output
level

R-CH
peak

R-CH
peak

L-CH
peak

L-CH
peak

screw
position

screw position

V

H

Screen Pattern

set

In phase 45˚

90˚

135˚

180˚

good

wrong

47 k

Ω

47 k

Ω

L-CH

R-CH

test tape
P-4-A100
(10 kHz, –10 dB)

LINE OUT

oscilloscope

forward side

reverse side

adjustment screws

Procedure:
–Forward Playback Mode–

(High speed adjustment)
1. Set to test mode. (Refer to page 10.)
2. Set to FWD playback mode.
3. Twice pressing the HIGH/NORMAL switch.
4. Adjust RV316 (DECK A), RV416 (DECK B) so that the

frequency counter reading becomes 5,980 

±

 20 Hz.

5. Release test mode after adjustment is completed.
(Normal speed adjustment)
1. Set to FWD playback mode.
2. Adjust RV317 (DECK A), RV417 (DECK B) so that the

frequency counter reading becomes 3,000 

±

 10 Hz.

(Pitch control adjustment) (DECK A) (TC-WE525 only)
1. Push the PITCH CONTROL switch.
2. Set RV986 (PITCH CONTROL knob) to mechanical center.
3. Set to FWD playback mode.
4. Adjust RV318 so that the frequency counter reading becomes

2,990 

±

 10 Hz.

Frequency difference between the beginning and the end of the tape
should be within 

±

 3%.

Frequency difference between the deck A and deck B the beginning
of the tape should be within 

±

 1.5%.

Adjustment Location: MAIN board (See page 13.)

Procedure:
–Forward Playback Mode–

set

frequency counter

47 k

Ω

LINE OUT

test tape
WS-48B
(3 kHz, 0 dB)

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 

±

 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 13.)

set

test tape
P-4-L300
(315 Hz, 0 dB)

level meter

LINE OUT

47 k

Ω

– 12 –

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

1. Connect the digital voltmeter to test point TP431.
2. Set RV131 (L-CH), RV231 (R-CH) to mechanical center.
3. Set to FWD record mode.
4. Adjust T131 (L-CH), T231 (R-CH) so that the digital voltmeter

reading becomes minimum.

Adjustment Value: Maximum 220 mV

Adjustment Location: MAIN board (See page 13.)

Setting:
REC LEVEL control : standard record position (See page 10.)

Procedure:
1. Record Mode

2. Playback Mode

set

AF OSC

attenuator

10 k

Ω

600 

Ω

LINE IN
1) 315 Hz
2) 10 kHz

38.8 mV (–26 dB)

blank tape
CS-123

Confirm that the 10 kHz playback output is 0 

±

 0.5 dB relative to

the 315 Hz output. If necessary, adjust RV131 (L-CH), RV231 (R-
CH) and repeat the steps given above.

Adjustment Location: MAIN board (See page 13.)

set

recorded
portion

level meter

LINE OUT

47 k

Ω

Setting:
REC LEVEL control : standard record position (See page 10.)

Procedure:
1. Record Mode

2. Playback Mode

set

AF OSC

attenuator

10 k

Ω

600 

Ω

LINE IN

blank tape
CS-123

315 Hz, 38.8 mV (–26 dB)

Confirm playback the tape recorded become adjustment level as
follows.
If necessary, adjust RV161 (L-CH), RV261 (R-CH) and repeat the
steps 1 and 2.

LINE OUT level : –26 

±

 0.5 dB (36.7 to 41.1 mV)

Adjustment Location: MAIN board (See page 13.)

set

recorded
portion

level meter

LINE OUT

47 k

Ω

set

3

2

1

blank tape
CS-413

TP431

L-CH

R-CH

digital
voltmeter

LINE IN
no signal