1-18
MECHANICAL ADJUSTMENTS
1-4: CONFIRMATION OF REEL BRAKE TORQUE
(S Reel Brake) (Refer to Fig. 1-2-B)
1.
2.
3.
4.
Once set to the Fast Forward mode then set to the Stop
mode. While, unplug the AC cord when the Pinch Roller
Block is on the position of Fig. 1-2-A.
Move the Idler Ass’y from the S Reel.
Install the Torque Gauge on the S Reel. Turn the Torque
Gauge clockwise.
Then, confirm that it indicates 60~100gf•cm.
(T Reel Brake) (Refer to Fig. 1-2-B)
1.
2.
3.
4.
Once set to the Fast Forward mode then set to the Stop
mode. While, unplug the AC cord when the Pinch Roller
Block is on the position of Fig. 1-2-A.
Move the Idler Ass’y from the T Reel.
Install the Torque Gauge on the T reel. Turn the Torque
Gauge counterclockwise.
Then, confirm that it indicates 30~50gf•cm.
Fig. 1-2-A
The position at FF mode.
Stop at this position.
The position at
STOP mode.
Capstan DD Unit
Cassette Holder Ass’y
Cassette Opener
Pinch Roller Block
Fig. 1-2-B
Torque Gauge
Torque Gauge
S Reel
T Reel
2. CONFIRMATION AND ADJUSTMENT OF
TAPE RUNNING MECHANISM
Tape Running Mechanism is adjusted precisely at the
factory. Adjustment is not necessary as usual. When you
replace the parts of the tape running mechanism because of
long term usage or failure, the confirmation and adjustment
are necessary.
2-1: GUIDE ROLLER
1.
2.
3.
4.
5.
6.
7.
Playback the VHS Alignment Tape (MHP).
Connect CH-1 of the oscilloscope to TP101 (Envelope)
and CH-2 to TP3002 (SW Pulse).
Press and hold the Tracking-Auto button on the remote
control more than 2 seconds to set tracking to center.
Trigger with SW Pulse and observe the envelope. (Refer
to Fig. 2-1-A)
When observing the envelope, adjust the Roller Driver
(PTU94002-2) slightly until the envelope will be flat.
Even if you press the Tracking Button, adjust so that
flatness is not moved so much. (Refer to Fig. 2-1-B)
Adjust so that the A : B ratio is better than 3 : 2 as shown
in Fig. 2-1-C, even if you press the Tracking Button to
move the envelope (The envelope waveform will begin to
decrease when you press the Tracking Button).
Adjust the PG shifter during playback.
(Refer to the ELECTRICAL ADJUSTMENTS)
NOTE
After adjustment, confirm and adjust A/C head.
(Refer to item 2-2)
Fig. 2-1-A
CH-1
Envelope
(TP101)
CH-1
Track
CH-2
Track
CH-2
SW Pulse (TP3002)
NOTE
If the torque is out of the range, replace the following parts.
Check item
1-3
Replacement Part
Idler Ass’y/Clutch Ass’y
S Reel side:
T Reel side:
S Reel/Tension Band/Tension
Connect/Tension Arm Ass’y
T Reel/T Brake Band//T Brake
Spring/T Brake Arm
1-4
Fig. 2-1-C
Entrance
Max
Exit
Max
A
B
A : B
≥
3 : 2
Fig. 2-1-B
Improper
Proper
(a) Guide roller
(b) P4 Cap