Toshiba SD-25VLSR Service Manual page 53

2-2: CONFIRMATION AND ADJUSTMENT OF AUDIO/
CONTROL HEAD
When the Tape Running Mechanism does not work well,
adjust the following items.
1. Playback the VHS Alignment Tape (Monoscope of ST-
C6 MODE2).
2. Confirm that the reflected picture of stamp mark is
appeared on the tape prior to P4 Cap as shown in Fig.
2-2-A.
a) When the reflected picture is distorted, turn the screw
1 clockwise until the distortion is disappeared.
b) When the reflected picture is not distorted, turn the
screw 1 counterclockwise until little distortion is
appeared, then adjust the a).
Turn the screw 2 to set the audio level to maximum.
3.
4. Confirm that the bottom of the Audio/ Control Head and
the bottom of the tape is shown in Fig. 2-2-C.
When the height is not correct, turn the screw 3 to
c)
adjust the height. Then, adjust the 1~3 again.
Audio/Control Head
Audio/Control Head
5
3
2
4
Audio/Control Head
Tape
MECHANICAL ADJUSTMENTS
Reflected picture of
Stamp Mark
P4 Cap
Stamp Mark
Fig. 2-2-A
[OK] [NG]
1
Fig. 2-2-B
0.25±0.05mm
Fig. 2-2-C
2-3: TAPE RUNNING ADJUSTMENT
(X VALUE ADJUSTMENT)
1. Confirm and adjust the height of the Reel Disk.
(Refer to item 1-1)
2. Confirm and adjust the position of the Tension Post.
(Refer to item 1-2)
3. Adjust the Guide Roller. (Refer to item 2-1)
4. Confirm and adjust the Audio/Control Head.
(Refer to item 2-2)
5. Connect CH-1 of the oscilloscope to TP102 and CH-2 to
TP103.
6. Playback the VHS Alignment Tape (Monoscope of ST-
C6 MODE2).
7. Press and hold the ATR button on the remote control
more than 2 seconds to set tracking to center.
Set the X Value adjustment driver (JG153) to the 4 of
8.
Fig. 2-2-B. Adjust X value so that the envelope
waveform output becomes maximum. Then, check if the
5 section of Fig. 2-2-B is on the center position (or
rather to the cylinder side). In case of the envelope
maximum at the difference position from the center,
adjust the matching of picture and sound again.
D2-3