SANYO VC MECHANISM
Service Manual

5-3-2. ADJUSTING THE GUIDE ROLLER (Refer to Fig. 5-3-2 and Fig. 5-3-3.)
(1) Play the alignment tape (NTSC:VHJ-0006, PAL:VHJ0009) and check that the envelope waveform has become maximum using the tracking center. Then rotate the �assy, roller, guide� of the supply and take up sides in the counterclockwise direction to loosen them, and then tighten them alternately until the envelope waveform becomes flat. If the envelope waveform is not maximum at the tracking center, refer to section 5-3-3, and temporarily adjust the �tracking (X value)� of the �assy, head r/p ace vc�. Note: Pressing the �CHANNEL + ( )� and CHANNEL � ( ) tracking buttons together resets to the tracking center. (2) Adjust the �assy, roller guide� at the supply side. 1) Press the tracking button (channel � ( )), and check that when the envelope waveform is set to the maximum 30 to 50%, the first half of the envelope waveform is not flat. If not flat, finely adjust the �assy, roller guide� of the supply side according to the following procedure. a. If the first half of the envelope waveform is as shown in Fig. 5-3-3 (a), as the �assy, roller, guide� of the supply side is pressed excessively, loosen the �assy, roller, guide� of the supply side to set the state shown in Fig. 5-3-3 (b), tighten again until the position that the envelope waveform becomes flat. b. If the first half of the envelope waveform is a radial shape as shown in Fig. 5-3-3 (c), tightening the �assy, roller, guide� of the supply side even further will not correct the radial shape as shown in Fig. 5-3-3 (d). In some cases, the flat part will bend in. In such cases, since the state shown in Fig. 5-3-3 (c) is normal, loosen the �assy, roller, guide� of the supply side, and tighten again until the envelope waveform becomes as shown in Fig. 5-3-3 (c). 2) Check that the output of the first half of the envelope waveform is below 80% of the maximum part at the tracking center. 3) Rotate the �assy, roller, guide� of the supply side in the counterclockwise direction by 20°. (3) Adjust the �assy, roller, guide� of the take up side. 1) Press the tracking button (channel � ( )), and check that when the envelope waveform is set to the maximum 30 to 50%, the latter half of the envelope waveform becomes flat. If not flat, slightly loosen the �assy, roller, guide� of the take up side, and then slightly tighten until it becomes flat. 2) Check that the output of the latter half of the envelope waveform is maximum at the tracking center. If not maximum, finely adjust the �assy, roller, guide� of the take up side.

(4) When set to F-SEARCH � PLAY, R-SEARCH � PLAY, check that the envelope waveform does not change. 1) If the first half of the envelope waveform changes, tighten the �assy, roller, guide� of the supply side in the clockwise direction by up to 20°. 2) If the latter half of the envelope waveform changes, adjust the �assy, roller, guide� of the take up side of step (3) again.
Pressed excessively Pressed inadequately

Normal

Eccentric screwdriver (VHJ- 0003) Supply side �assembly, roller, guide�

Take up side �assembly, roller, guide�

Adjust so that the tape path along the cylinder lead face. Fig. 5-3-2

Adjust so that the envelope waveform becomes flat when maximum at the tracking center.
100%

Normally, the envelope waveform becomes flat even at 30 to 50%.

30 ~ 50%

(a) Supply side �assembly, roller, guide� is excessively pressed.
30 ~ 50%

(b) Take up side �assembly, roller, guide� is inadequately pressed.
30 ~ 50%

(c) When the radial waveform is normal.
30 ~ 50%

(d) Supply side �assembly, roller, guide� is excessively pressed.
30 ~ 50%

Fallen part Fig. 5-3-3

� 31 �