Sharp VT-3448X, Руководство по обслуживанию

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HEIGHT ADJUSTMENT OF REVERSE GUIDE
ADJUSTMENT OF TAPE DRIVE TRAIN
[Height adjustment of reverse guide]
Remove the cassette housing control assembly.
Make a short-circuit between
and both
located at the right on your side on the main Now plug
in the AC cord.
Reverse guide height
Use the mm side.
adjusting jig
Ret-verse guide
Reverse guide height
mm
side
adjusting jig
Figure
In the tape load mode, make adjustment at the
side first and then rotate the reverse guide adjuster nut by
0 turn counterclockwise.
Actually load the unit with a tape, put it in the play mode, and
make sure the tape is free from wrinkles near the reverse
guide.
Use a commercially available box driver to turn the height
adjusting nut.
driver
Height adjusting nut
Figure
Check and adjust the position of the tension pole. (See page
Check and adjust the video search rewind back tension.
(See page
Set the A/C head. (See page
Rough adjustment of tape drive train.
a) Connect the oscilloscope to the test point for
envelope output The signal is to
be triggered by the head switching pulse
Loosen the setscrew at the lower part of the guide roller,
and adjust it with an adjusting Hex
so that the guide roller turns smoothly. (Do not overloosen
the setscrew, which causes insecurity of the guide roller.)
(See Figure
Set the alignment tape (monoscope pattern) on the reel
disk, and place the unit in the playback mode. (Place a
g weight on the cassette tape to prevent floating of
the cassette tape.)
Guide roller
Cassette tape
Hexagon wrench
Figure Figure
In the X value adjustment mode (see the Electrical
Adjustment), change the envelope waveform from MAX
to
and to MAX by pushing the or tracking
button, and check a flat response is obtained on the
waveform.
If a flat response cannot be obtained, roughly adjust the
guide rollers on the supply side and take-up side using
an adjusting screw driver until a flat response can be
obtained.
Tighten the screw to eliminate wrinkles from the tape
of the retain guide flange area.
Replace the tape to check the tape on the retain guide
flange area for wrinkles.
No wrinkle is present.
Turn the screw clockwise to generate wrinkles on
the tape at the flange area, and then back off the
screw as far as the wrinkles are just eliminated.
Wrinkles are present.
Turn the screw counterclockwise as far as the
wrinkles are just eliminated.
Reference:
If the screw is turned clockwise, wrinkles will be
produced on the lower flange.