MECHANICAL ADJUSTMENTS
Beginning Ending Audio/Control Head Maximum A B Maximum
A:B=3:2
Fig. 2-1-B 2-2: CONFIRMATION AND ADJUSTMENT OF A/C HEAD TILT When the tape is running abnormally, perform the following adjustments. 1. Insert a new tape and play it back. 2. Confirm that there is no crease on the tape between the P4 post and guide roller (R) and the tape is running smoothly. (It is absolutely impossible to get satisfactory sound if the tape is distorted between the A/C head and P4 post.) 3. If the tape still does not run smoothly, turn the screw 1 and adjust the tilt of the A/C head. (Refer to Fig. 2-2)
Drum
0.25mm
Video Tape Video Tape
Fig. 2-3 2-4: TAPE RUNNING ADJUSTMENT 1. Adjust the height of reel disk. (Refer to item 1-1) 2. Confirm and adjust tension post position. (Refer to item 1-2) 3. Adjust the guide roller. (Refer to item 2-1) 4. Adjust the A/C head tilt. (Refer to item 2-2) 5. Adjust the A/C head height and azimuth. (Refer to item 2-3) 6. Connect CH-1 on the oscilloscope to TP4001 and CH-2 to TP4002. Playback the VHS alignment tape (JG001C). Set the tracking to manual center. Adjust X with the screw driver for X (JG153) as the Fig. 2-1-A and Fig. 2-1-B. (Refer to No. 2 of the item 2-1).
Guide Roller R Tape
1
2
Audio/Control Head P4 Post
3
X Value Adjustment Driver Hole
Fig.2-2
2-3: ADJUSTMENT OF A/C HEAD HEIGHT AND AZIMUTH 1. Playback a VHS alignment tape (JG001C) and observe the waveform at the audio output terminal. 2. Turn the screw 2 slowly to change the azimuth of the A/C head. Adjust the height so that the audio output becomes maximum. (Refer to Fig. 2-2) 3. Adjust the screw 3, (Refer to Fig. 2-2) until the height of the A/C head reaches the position against the tape as shown in Fig. 2-3. 4. When the control head height is not correct. (When you must turn the screw more than 45 degrees), Turn all of the screws 1, 2 and 3 to the same degrees. Then confirm the angle of the audio/control head and adjust again.
