Cassette Deck Section Adjustments; Playback Adjustment; Recording Adjustment - Pioneer XR-A6800 Service Manual

XR-A6800, XR-A4800
QQ
3 7 63 1515 0
6.2 CASSETTE DECK SECTION
6.2.1 For XR-A6800
• Adjustment points and test points are shown in Fig.3, Fig.5 and Fig.7.
Mechanical Adjustment
• Test tape : NCT-111 (3kHz, 30min).
1. Tape Speed Adjustment
No. Mode Test Tape
NCT-111
Deck Ι
1
(Playback : 3kHz)
PLAY
TE
L 13942296513
Electrical Adjustment
Check the following before starting.
(1) Confirm that the tape speed adjustment has been completed.
(2) Clean the heads and demagnetize them using a head eraser.
(3) Set the measurement level to 0 dBV = 1 Vrms.
(4) Use the specified tape for adjustment. Use the labeled (A)
side of the test tape.
STD-331E : For playback check
STD-632 : Normal blank tape
(5) Provide yourself with the following measuring devides:
• AC millivoltmeter
• Low-frequency oscillator
• Attenuator
• Oscilloscope
(6) Adjust both right and left channels unless otherwise specified.
(7) Turn the DOLBY NR switch off unless otherwize specified.
(8) Warm up the unit for several minutes before adjustment.
In particular, be sure to warm up the unit in the REC/PLAY
mode for 3 to 5 minutes before starting recording/playback
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frequency characteristics adjustment.
(9) Always follow the indicated adjustment order.
Otherwise, a complete adjustment may not be achieved.
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Adjusting Measurement
Points Points
ADJ. VR on
TAPE TEST
CASSETTE
POINT (Rch)
MECHA (Fig. 3)
(AF Assy)
AF Assy
Fig.3 Tape Speed ADJ. Point
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2 9
8
Adjustment Procedure
Press the PLAY SW and adjust so that the reading
becomes 3000Hz ± 20Hz. Confirm that wow & flutter
level is below 0.3% (in the reverse direction, confirm
that the reading is within 3000Hz ± 60Hz).
Front Side
Q Q
3 6 7 1 3 1 5
Playback Adjustment (Decks Ι and ΙΙ)
(1) Head Azimuth Adjustment
(2) Playback Level Adjustment
Recording Adjustment (Deck Ι)
(1) Bias Oscillation Frequency Adjustment
(2) Recording Bias Adjustment
(3) Recording Level Adjustment.
(4) ALC Operation Check
∗ As the reference recording level is 250nwb/m for STD-331E,
the recording level will be higher by 4 dB for STD-331B
(160nwb/m). When adjusting, pay carefull attention to the type
of tape used.
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.
9 4 2 8
Remarks
Tape Speed
ADJ. VR
Cassette
Mechanism
Section
(Side View)
0 5 8 2 9 9 4 2 8
m
9 9
9 9