13VT-N200
3. Tape run adjustmentPB CHROMA
1 Connect the oscilloscope to PB CHROMA envelope
Envelope
output test point, set oscilloscope sync to EXT,
trigger-input the PB CHROMA signal (head switch-
ing pulse).
2 Rough adjustment of X value
Tentatively fix A/C head arm screws 1 and 2 byCH-1CH-2
the method described in Page 30 "Replacement 3".Head switching pulse
After shortcircuiting TP7701 and TP7702, plug in the
Figure 1-34.
powercord, then turn on the power. And playback the
alignment tape (VRONBZGS). As a result the auto-
from min to max. At this time adjust the height of
tracking is automatically cancelled, so that the Xsupply and take-up side guide roller with the adjust-
value adjustment mode is set.
ment driver (JiGDRiVERH-4) so that the envelope
Move the A/C head with the X value adjustment gearwaveform changes nearly parallel.
driver (JiGDRiVER-6) by the method shown in Figure
4 If the tape is lifted or sunk from the helical lead
1-33, and adjust the A/C head so as to get thesurface, the PB CHROMA envelope waveform ap-
maximum envelope waveform. (Note: When the A/Cpears as shown in Figure 1-35.
head is adjusted, adjust so that the maximum en-
5 Press the tracking button (+), (�) and make sure that
velop waveform is obtained nearest the position ofthe envelope waveform changes nearly parallel.
initial setting made in Page 30.)
6 Finally check tape crease near the reverse guide. If
3 Next, change the alignment tape to VROEFZCS totape crease is found, remove it as stated in Page 31
play back. Press the tracking button (+), (�) and
"HEIGHT ADJUSTMENT OF REVERSE GUIDE"
change the envelope waveform from max to min anditem 3.
When the tape is above the helical lead.When the tape is below the helicallead.
Supply sideTake-up sideSupply sideTake-up side
Supply side guide rollerTake-up side guide rollerSupply side guide rollerTake-up side guide roller
rotated in clockwiserotated in clockwiserotated in counterclock-rotated in counterclock-
direction (lowers guidedirection (lowers guidewise direction (raiseswise direction (raises
roller) to flattenroller) to flattenguide roller) to make theguide roller) to make the
envelope.envelope.tape float above the helicaltape float above the
Adjustmentlead. The supplyhelical lead. The take-up
side guide roller is thenside guide roller is then
rotated in the clockwiserotated in the clockwise
direction to flatten thedirection to flatten the
envelope.envelope.
Figure 1-35.
4. A/C head X value adjustmentFinal tightening torque is 0.6Nám (If the screw 2 is
1 Tentatively fix A/C head arm screws 1 and 2 bytightened first, the X value may deviate.)
the method described in Page 30 "Replacement 3".5 Adjust the playback switching point (Refer to the
2 After shortcircuiting TP7701 and TP7702, plug in theelectric adjustment method.)
powercord, then turn on the power. And playback the6 Playback the self-picture-recorded tape, and check
alignment tape (VROEFZCS). As a result the auto-the flatness of envelope waveform and sound.
tracking is automatically cancelled, so that the XNote:
value adjustment mode is set.When the A/C head X value adjustment is performed, be
3 Move the A/C head with the X value adjustment gearsure to perform at first X value rough adjustment (refer to
driver by the method shown in Figure 1-33, andPage 33, 3-2).
1
adjust the A/C head so as to get the maximum2
envelope waveform. (Note: At this time adjust so as
to get the maximum envelope waveform nearest the
A/C head position which has been set in case of X
value rough adjustment as stated in Page 33, 3- 2.)
4 Tighten finally the screws 1 and 2. Be sure to
tighten at first the screw 1 and then the screw 2.Figure 1-36.
33 |
ACEC
SHARP
