1-34
KW-XC828
Mechanism Adjustment Section
Item
Adjusting & Confirmation Methods
1.Head azimuth
2. Tape Speed
and
Wow & Flutter
Std. Value
Adjust
"Head Height Adjustment"
Note
Adjust the azimuth directly. When you adjust the height using a
mirror tape, remove the cassette housing from the mechanism
chassis. After installing the cassette housing, perform the azimuth
adjustment.
1. load the mirror tape (SCC-1659). Adjust with height adjustment
screw A and azimuth adjustment screw B so that line "A" of
the mirror tape runs in the center between Lch and Rch in the
reverse play mode.
2. After switching from REV to FWD then to REV, check that the
head position set in procedure "1" is not changed.
*If the position has shifted, adjust again and check.
3. Adjust the azimuth screw B so that line "B" of the mirror tape
runs in the center between Lch and Rch in the forward play
mode.
"Head Azimuth Adjustment"
1. Load the test tape (VT724: 1kHz) and play it back in the
reverse play mode. set the Rch output level to maximum.
2. Load the test tape (VT703: 10kHz) and play it back in the
forward play mode. Adjust the Rch and Lch output levels to
maximum, with azimuth adjustment screw B .
In this case, the phase difference should be within 45 .
3. Engage the reverse mode and adjust the output level to
maximum, with azimuth adjustment screw C .
4. When switching between forward and reverse modes, the
difference between channels should be within 3dB.
*Between FWD Lch and Rch, REV Lch and Rch.
5. When the test tape (VT721 (315Hz )) is played back, the level
difference between channels should be within 1.5dB.
Less than
0.35%
(JIS RMS)
3. DOLBY NR
level adjustment
1. Check to see if the reading of the frequency counter & Wow
flutter meter is within 3015-3045 Hz (FWD/REV), and less than
0.35% (JIS RMS).
2. In case of out of specification, adjust the motor with a built-in
volume resistor.
Tape Speed
3015-3045Hz
Wow & Flutter
Built-in
volume resistor
1. Play the test tape (VT724 : 1kHz) back.
2. Adjust the VR191 (Lch) and VR291 (Rch) so that the DOLBY NR
level is 27.5mV 0.5dB by TP191 (Lch), TP291 (Rch).
Speaker out
1kHz/10kHz
: -1dB 3dB,
63Hz/1kHz
: 0dB 3dB,
Playback head
Height adj.
REV adj.
FWD adj.
Head shield
Head shield
The head is at low position
during FWD.
The head is at height position
during REV.
VR191:Lch
VR291: Rch
0
45
Phase
B
C
A