JVC KD-A66 - Main Adjustments (Continued); Specific Mechanical Adjustments

KD-A66A/B/C/E/J/U
point
value
Employ a special cassette (C-120) Screw ©
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 cas-
sette tape. Adjust-the screw © until
the tape runs in the center of the erase
head tape guide.
(See “Troubleshooting hints’’ afore-
said.) Incorrect
Correct Tape guide
Tape guide =
EF Tape guide
LL.
Be sure to perform this adjust-
ment after replacing the erase
head.
Adjusting erase
head height
Adjusting motor) Connect a speed meter (an electronic Semi- 3000 Hz If the speed meter functions as a
speed counter) to the LINE OUT terminals. fixed wow and flutter meter, also,
Playback the VTT-656 test tape. resistor connect the deck to the INPUT
Adjust the semi-fixed resistor in the in the terminals of the meter.
motor until the reading of the speed motor
meter is 3000 Hz.
Checking play- Employ a torque testing cassette tape 40—70 If the standard torque is not
obtained, replace the take-up
disc assembly.
for the checking, or remove the cas-
sette cover and use a torque gauge.
back torque
More than
70gr-cm
If the standard torque is not
obtained, perform the following.
1. Clean the capstan belt, the
idler circumference, the
motor pulley, the take-up
reel disc circumference, the
flywheel circumference, etc.
. Replace the belt and idler.
Measure the torque in the fast forward
mode in the same manner as in the
above.
Checking fast
forward torque
Checking More than
rewind
torque
Measure the torque in the rewind
mode in the same manner as in the
above.
If the standard torque is not
obtained, clean the capstan belt,
idler, motor pulley, flywheel
circumference, rewinding idler
circumference, left reel disc
circumference, etc.
Connect a wow and flutter meter to
LINE OUT terminals.
Playback the VTT-656 test tape.
Check to see if the reading of the
meter is within 0.05% (WRMS).
If the reading becomes moving
value even if conforming to the
standard, a re-claim may be
raised. Repairs are necessary.
Checking wow
and flutter
No. 4193 AAS
sie