JVC PC-5 L User Manual

PC-5 L/LB |
Adjustments
1. Adjustment Procedure of Cassette Mechanism
(Adjust the mechanism or confirm that it is in normal operating condition prior to the adjustment of the electrical circuit.)
Item
Adjusting
|
Standard
:
point
value
. Connect an electronic voltmeter to
the LINE OUT terminals.
. Play back the VTT-658 test tape.
. Adjust the head angle with the
screw (A) until the reading of the
electronic voltmeter becomes maxi-
mum for both channels.
4. After adjusting, set the screw with
screw bond.
Adjusting
record/playback
head position
WRN
Screw (A) | Maximum | If the head is worn, disconnected or
exceedingly magnetized so as not to
provide the necessary characteristics,
replace it with a new one.
After replacement, the head position
adjustment as well as the playback
level adjustment, the bias current ad-
justment and the recording level ad-
justment are all necessary.
lf the output difference between the
left and right channels exceeds 3 —
4 dB, the head is defective.
Replace it with a new one.
Screw ©
Employ a special cassette ’ (C-120)
from which parts of the casing, where
the erase head, record/playback head
and capstan engage, has been cut
away. Perform tape transport with the
cassette tape. Adjust the screw
until the tape runs in the center of the
erase head tape guide.
Adjusting erase
head height
Incorrect
Correct Tape guide
Tape guide ia
Er Tape guide
i Tape
Connect a speed meter (an electronic
counter) to the LINE OUT terminals.
Play back the VTT-656 test tape.
Adjust the semi-fixed resistor in the
motor until the reading of the speed
meter is 3000 Hz.
Semi-
fixed
resistor
in the
Adjusting motor
speed
Employ a torque testing cassette tape
for the checking.
Checking play-
back torque
Checking fast
forward torque
Measure the torque in the fast forward
mode in the same manner as in the
above.
Checking rewind
torque
Measure the torque in the rewind
mode in the same manner as in the
above.
Connect a wow and flutter meter to
LINE OUT terminals.
Play back the VTT-656 test tape.
Check to see if the reading of the
meter is within 0.04% (WRMS).
Checking wow
and flutter
No. 1443
3000 Hz
—70
- cm
80 gr-cm
80 gr-cm
More than
More than
Be sure to perform this adjustment
after replacing the erase head.
If the speed meter functions as a
wow and flutter meter, also, connect
the deck to the INPUT terminals of
the meter.
If the standard torque is not ob-
tained, replace the take-up disc
assembly.
If the standard torque is not ob-
tained, perform the following.
1. Clean the capstan belt, the idler
circumference, the motor pulley,
the take-up reel disc circumfer-
ence, the flywheel circumference,
etc.
2. Replace the belt and idler.
If the standard torque is not ob-
tained, clean the capstan belt, idler,
motor pulley, flywheel circum-
ference, rewinding idler circum-
ference, left reel disc circumference,
etc.
If the reading becomes moving value
even if conforming to the standard, a
re-claim may be raised. Repairs are
necessary.

JVC PC-5 L Specifications

General

Brand	JVC
Model	PC-5 L
Category	Stereo System
Language	English