Toshiba MW27F51 Service Manual - Page 44

MECHANICAL ADJUSTMENTS 1-4: CONFIRMATION OF VSR TORQUE 1. Install the Torque Gauge (JG002F) and Adapter (JG002B) on the S Reel. Set to the Picture Search (Rewind) mode. (Refer to Fig.1-4-B) 2. Then, confirm that it indicates 120~180gf•cm. NOTE Install the Torque Gauge on the reel disk firmly. Press the REW button to turn the reel disk. 1-5: CONFIRMATION OF REEL BRAKE TORQUE (S Reel Brake) (Refer to Fig. 1-4-B) 1. 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. 1-4-A. 2. Move the Idler Ass'y from the S Reel. 3. Install the Torque Gauge (JG002F) and Adapter (JG002B) on the S Reel. Turn the Torque Gauge (JG002F) clockwise. 4. Then, confirm that it indicates 60~100gf•cm. (T Reel Brake) (Refer to Fig. 1-4-B) 1. 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. 1-4-A. 2. Move the Idler Ass'y from the T Reel. 3. Install the Torque Gauge (JG002E) and Adapter (JG002B) on the T reel. Turn the Torque Gauge (JG002E) counterclockwise. 4. Then, confirm that it indicates 30~50gf•cm. The position at FF mode. Pinch Roller Block Stop at this position. The position at STOP mode. Capstan DD Unit Cassette Opener Cassette Holder Ass'y Fig. 1-4-A NOTE If the torque is out of the range, replace the following parts. Check item Replacement Part 1-4 Idler Ass'y/Clutch Ass'y 1-5 S Reel side: S Reel/Tension Band/Tension Connect/Tension Arm Ass'y T Reel side: T Reel/T Brake Band//T Brake Spring/T Brake Arm 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. Playback the VHS Alignment Tape. 2. Connect CH-1 of the oscilloscope to TP4501 (Envelope) and CH-2 to TP102 (SW Pulse). 3. Press both VOL. DOWN button on the set and the Channel button (5) on the remote control for more than 2 seconds to set tracking to center. 4. Trigger with SW Pulse and observe the envelope. (Refer to Fig. 2-1-A) 5. When observing the envelope, adjust the Taper Nut Driver slightly until the envelope will be flat. Even if you press the Tracking Button, adjust so that flatness is not moved so much. 6. Adjust so that the A : B ratio is better than 3 : 2 as shown in Fig. 2-1-B, even if you press the Tracking Button to move the envelope (The envelope waveform will begin to decrease when you press the Tracking Button). 7. 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) Torque Gauge/Adapter (JG002F/JG002B) Torque Gauge/Adapter (JG002E/JG002B) CH-1 Envelope (TP4501) CH-2 SW Pulse (TP102) CH-1 CH-2 Track Track S Reel T Reel Fig. 1-4-B D2-2 Entrance Fig. 2-1-A Exit Max A B Max A : B ≥ 3 : 2 Fig. 2-1-B