Sharp DV-NC150U Service Manual page 97

1-D. Azimuth Alignment of Audio/
Control/ Erase Head
Purpose:
To correct the Azimuth alignment so that the Audio/
Control/Erase Head meets tape tracks properly.
Symptom of Misalignment:
If the position of the Audio/Control/Erase Head is not
properly aligned, the Audio S/N Ratio or Frequency
Response will be poor.
1. Connect the oscilloscope to the audio output jack on
the rear side of the deck.
2. Playback the Test Tape (9HSFL8NW) and confirm
that the audio signal output level is 8kHz.
3. Adjust Azimuth Adj. Screw so that the output level on
the AC Voltmeter or the waveform on the oscilloscope
is at maximum. (Fig. M6)
Note: Upon completion of the adjustment of Azimuth Adj.
Screw, check the X Value by pushing the CH UP or
DOWN buttons alternately, to check the symmetry of the
envelope. Check the number of pushes to ensure preset
position. The number of pushes CH UP button to achieve
1/2 level of envelope should match the number of pushes
CH DOWN button from center. If required, redo the "X
Value Alignment."
1-E. Checking and Alignment of
Tape Path during reversing
Purpose:
To make sure that the tape path is well stabilized during
reversing.
Symptom of Misalignment:
If the tape path is unstable during reversing, the tape will
be damaged.
Note: Do not use an Test Tape for this procedure. If the
unit is not correctly aligned, the tape may be damaged.
1. Insert a black cassette tape into the tray and set the
unit to REV. Then confirm if the tape has been curled
up or bent at the Take-up Guide Post [4] or REV Post
[5] (Refer to Fig. M11 and M12.)
2. When the tape has been curled up or bent, turn the
alignment screw to adjust the height of REV Post.
(Refer to Fig. M11 and M13.)
Take-up Guide Post [4]
Correct
REV Post
Tape
Take-up Guide
Post
Tape
2-3-5
REV Post [5]
Fig. M11
Incorrect
Fig. M12
Alignment
Screw
Tape Guide
Assembly
Fig. M13
H9745MA