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13

Procedure:
Mode: playback

1. Set to the test mode (See page 12).
2. Press the

H

button to playback.

3. Adjust RV301 so that the frequency counter reading becomes

3,000±90 Hz.

4. Frequency difference between the beginning and the end of

the tape should be within 3%.

Adjustment Location: MAIN board (See page 14)

Sample value of Wow and Flutter: 0.3% or less W.RMS (JIS)

(WS-48B)

Procedure:
Mode: playback

Adjust RV121 (L-CH) and RV221 (R-CH) so that the reading on
level meter meets 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

Check that the LINE OUT level does not change even if playback
and stop operation is repeated several times.

Adjustment Location: MAIN board (See page 14)

+
–

set

LINE OUT jack (J301)

frequency counter

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

47 k 

Ω

+
–

set

LINE OUT jack (J301)

47 k 

Ω

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

level meter

1. Set RV141 (L-CH) and RV241 (R-CH) to mechanical center

and turn the set recording mode.

2. Connect digital voltmeter as shown by the following table.
3. Press the H button to playback.
4. Adjust the following transformers for the minimum readings

on the digital voltmeter.

Measurement Point

Adjustment Part

Value

L-CH

TP301 pin 2 and 3

T101

minimum

R-CH

TP301 pin 1 and 2

T201

Specified value: Maximum 220 mV

Adjustment Location: MAIN board (See page 14)

[REC LEVEL]

 volume: standard record position (See page 12)

Procedure:
Mode: record and playback

1. Set to the test mode (See page 12).
2. Press the 

[REC    ]

 button then the

H

button to start record-

ing.

3. Press the

x

button to stop recording and press the

H

button

to playback.

4. Adjust TC-KE240: RV142 (L-CH) and RV242 (R-CH), TC-

RE340: RV141 (L-CH) and RV241 (R-CH) so that 10 kHz
playback output is 0±0.3 dB relative to the 315 Hz output.

Adjustment Location: MAIN board (See page 14)

–
+

set

LINE IN jack (J301)
(no signal)

TP301

3

2

1

L-CH

R-CH

47 k

Ω

digital voltmeter

CS-413 blank tape

set

47 k 

Ω

AF OSC

Attenuator

LINE IN jack (J301)
315 Hz
10 kHz

50 mV (–23.8 dB)

600 

Ω

10 k 

Ω

CS-123
blank tape

LINE OUT jack (J301)

level meter

+

–

TC-KE240

TC-RE340

adjustment screw

adjustment screw

z

Adjustment Location: record/playback head

14

[REC LEVEL]

 volume: standard record position (See page 12)

Procedure:
Mode: record and playback

1. Set to the test mode (See page 12).
2. Press the 

[REC    ]

 button then the

H

button to start record-

ing.

3. Press the

x

button to stop recording and press the

H

button

to playback.

4. Adjust RV101 (L-CH) and RV201 (R-CH) so that the reading

on level meter meets the adjustment limits below.

Adjustment Limits: –23.8±0.5 dB (47.2 to 53 mV)

set

47 k 

Ω

AF OSC

Attenuator

600 

Ω

10 k 

Ω

CS-123
blank tape

LINE OUT jack (J301)

level meter

LINE IN jack (J301)
315 Hz, 50 mV (–23.8 dB)

+
–

z

Record Bias

Adjustment

RV242 (R-CH)
RV142 (L-CH)

(TC-KE240)

RV301

Tape Speed Adjustment

T101
L-CH

T201

R-CH

Bias Consumption
Current Adjustment

LINE

OUT

LINE

IN

J301

Record Level

Adjustment

RV201 (R-CH)
RV101 (L-CH)

Playback Level

Adjustment

RV221 (R-CH)
RV121 (L-CH)

Record Bias

Adjustment

RV141 (L-CH)
RV241 (R-CH)

TP301

3
1

(TC-RE340)

15

Note on Schematic Diagram:
• All capacitors are in µF unless otherwise noted.  pF: µµF

50 WV or less are not indicated except for electrolytics
and tantalums.

• All resistors are in 

Ω

 and 

1

/

4

 

W or less unless otherwise

specified.

•

%

: indicates tolerance.

•

f

: internal component.

•

5

: fusible resistor.

•

C

: panel designation.

•

U

: B+ Line.

•

V

: B– Line.

•

H

: adjustment for repair.

• Voltages and waveforms are dc with respect to ground

under no-signal conditions.
no mark : STOP
(

) : PB

〈〈

 

〉〉

: REC

∗

: Impossible to measure

• Voltages are taken with a VOM (Input impedance 10 M

Ω

).

Voltage variations may be noted due to normal produc-
tion tolerances.

• Waveforms are taken with a oscilloscope.

Voltage variations may be noted due to normal produc-
tion tolerances.

• Circled numbers refer to waveforms.
• Signal path.

E

: PB

a

: REC

• Abbreviation

SP

: Singapore model

AUS

: Australian

Note: The components identified by mark 

0

 or dotted line

with mark 

0

 are critical for safety.

Replace only with part number specified.

Note on Printed Wiring Boards:
•

X

: parts extracted from the component side.

•

Y

: parts extracted from the conductor side.

•

b

: Pattern from the side which enables seeing.

16

TRANS board

MAIN board

LEAF SW board

POWER SW board

DISPLAY board

HEAD RELAY board

KEY board

HP board