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18
Tape Speed Adjustment (Deck B)
Note: Set the test mode using the following method and begin tape
speed adjustment.
In the test mode, the speed will switch to double speed or
normal speed each time the HI-DUB button is pressed.
Procedure:
With the power turned ON, press the
x
button, DISPLAY button,
and DISC 3 button simultaneously.
(The “TEST MODE” on the fluorescent indicator tube will be
displayed while in the test mode.)
To exit the test mode, press the
"/1
button.
1. Insert the WS-48B into deck B.
2. Press the
N
button of deck B.
3. Press the HI-DUB button and play the tape at double speed.
4. Adjust RV1001 of the LEAF SW board so that the reading of
the frequency counter becomes 6000 ± 180 Hz.
5. Press the HI-DUB button and play the tape at normal speed.
6. Adjust RV1002 of the LEAF SW board so that the reading of
the frequency counter becomes 3000 ± 90 Hz.
Adjustment Location:
– LEAF SW BOARD (Component Side) –
Deck A is RV311 (L-CH) and RV411 (R-CH), deck B is RV301
(L-CH) and RV401 (R-CH) so that adjustment within the following
adjustment level.
Adjustment level:
CN301 playback level: 301.5 to 338.3 mV (–8.2 to –7.2 dB)
level difference between the channels: within ± 0.5 dB
Adjustment Location: AUDIO board
Test tape
P-4-L300
(315Hz, 0dB)
Level meter
Set
MAIN board
CN301
1
(L-CH),
CN301
3
(R-CH)
+
–
RV1002 Tape Speed (Normal)
RV1001 Tape Speed (High)
Record Bias Adjustment (Deck B)
Procedure:
INTRODUCTION
When set to the test mode performed in
Tape Speed Adjust-
ment
,
when the tape is rewound after recording, the “REC memory
mode” which rewinds only the recorded portion and playback is
set.
This “REC memory mode” is convenient for performing this ad-
justment. During recording, the input signal FUNCTION will auto-
matically switch to VIDEO.
(After recording, press the
m
button without stopping will re-
turn to the position where recording was started)
1. Press FUNCTION button to select VIDEO. (This step is not
necessary if the above test mode has already been set)
2. Insert a tape into deck B, press the REC PAUSE/START button,
and then press the
N
button of deck B to start recording.
3. Mode: Record
5. Confirm playback the signal recorded in step 2 become adjust-
ment level as follows.
If these levels do not adjustment level, adjust the RV341 (L-CH)
and RV441 (R-CH) on the AUDIO board to repeat steps 3 and 4.
Adjustment level: The playback output of 10 kHz level difference
against 315 Hz reference should be ± 1.0 dB.
Adjustment Location: AUDIO board
4. Mode: Playback
Recorded
position
Level meter
Set
MAIN board
CN301
1
(L-CH),
CN301
3
(R-CH)
+
–
AF OSC
Blank tape
CS-123
Set
Attenuator
600
Ω
VIDEO (AUDIO) IN
1) 315 Hz
2) 10 kHz
50 mV (–23.8 dB)
Sample Value of Wow and flutter
W.RMS (JIS) less than 0.3%
(test tape: WS-48B)
Playback Level Adjustment (Deck A, Deck B)
Procedure:
Mode: Playback
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