JVC HR-XV45SEF, Руководство по обслуживанию

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(No.YD070)1-27
4.3.8 Adjustment after Drum Assembly (Video Heads)
4.3.9 Check of Traveling Device after Deck Assembly
4.3.9.1
Audio, RF Normalization Time (Locking Time) Check in Play after CUE or REV
4.3.9.2 Check of Tape Curl and Jam Status
Checking/Adjustment Procedure
1) Play the blank tape and check whether the guide roller
crumbles or wrinkles the tape and adjust it if necessary.
2) Check that the RF envelope output waveform is flat, and
adjust the height of the guide roller while playing the
alignment
tape.
3) Adjust the switching point.
4) Check the RF envelope output is the maximum when
the tracking control locates at the center. If not maximum,
set up to ensure that RF envelope output becomes the
maximum by turning the (+) type driver on the base A/C
groove.
Fixtures and tools used Connection position VCR (VCP) status Adjustment position
Oscilloscope
Alignment tape
(only for SP)
Post Height Adjusting
Driver
Driver (+) Type 5mm
CH-1: PB RF Envelope
CH-2: NTSC : SW 30Hz
PAL:SW
25Hz
Head switching output
point
RF Envelope output
point
Play the blank tape.
Play the Alignment tape. Fine adjustment of
guide roller
Switching Point
Tracking Preset
X-value
Purpose of adjustment : To adjust and stabilize the height change, X-value change, etc
depending on the guide roller after assembling the drum.
RF ENVELOPE OUTPUT POINT
V2 V1 V1
V1/V MAX = 0.7
V1/V MAX = 0.8
RF ENVELOPE OUTPUT
HEAD RF SWITCHING OUTPUT POINT
OSCILLOSCOPE
Connection Diagram
Waveform
CH-2 CH-1
Checking Procedure
1) Check that locking time of the RF and Audio waveform is
fallen within the measuring standard in conversion of the
play mode from the CUE or the REV mode. 2) Readjust the paragraph 4.3.6 and 4.3.7 if it deviates
from the standard.
Fixtures and tools used Measuring standard Connection position VCR (VCP) status
Oscilloscope
Alignment tape
(Colour bar)
Stop Watch RF Locking Time: Within
5 seconds
Audio Locking Time :
Within 10 seconds CH-1: PB RF Envelope
CH-2: Audio output
RF Envelope output
point
Audio output jack Play the Alignment
tape (Colour bar)
Checking Procedure
1) Check there is no abnormality of every traveling post
status.
2) There must be no abnormal operation of the counter in
occurrence of folding of the bottom tape. There must be
not abnormality of audio signal in damage of the top tape.
3) If there is abnormality, readjust the adjustment paragraph
4.3.5 and 4.3.6.
Fixtures and tools used Fixtures and tools used Fixtures and tools used
E-240 Tape
E-160 Tape There must be no jam or curl at the
first, middle and end position of tape. Travel the tape at the position
of its first and end.