JVC KD-2A - Mechanical Adjustment; Rewind Torque and Auto-stop Adjustment; Repair of Wow Flutter; Troubleshooting Flutter Causes

| KD-2A/B/C/E/J/U
Procedure Remarks
REW torque Measure as same way at REW 70 gr-cm | (If not)
mode. or more 1, Clean the main belt, idler and
rubber rim of it, and motor
pulley, rim of the flywheel
. Replace the reel disc.
Auto-stop Loosen 2 screws fastening the Check if the locking and sliding
mechanism solenoid and move it position parts of the operation button
for adjustment. cam are well coated with molyb-
denum.
Repair of Wow Flutter
{f wow and flutter increase, check the following points.
If there is defect in revolving parts, the wow and flutter
generated will increase in proportion to the number of
revolutions.
Play a 3000Hz test tape, and defective part can be detected
from the sound.
ee
Capstan and Capstan shaft has excessive run-out.
flywheel Flywheel turns heavily.
(shaft seisure, thrust play, etc.)
Replace flywheel.
Clean the capstan shaft and the groove in the
flywheel.
Apply oil to the metal position.
Replace the capstan assembly.
Replace pinch roller, or pinch roller spring.
Clean the pinch roiler or apply oi! to the rotary
shaft.
Adjust the pinch roller so that it is parallel with
the capstan shaft.
Replace the pinch roller spring.
Rough rotation (Deformation
scratches, or dust).
The angular position of the pinch
roller is not correct.
The pinch roller pressure is not correct.
Pinch roller
Clean the belt.
Replace the belt.
Belt has undue run-out.
Belt is dirty or slippery.
Replace back tension spring (under supply disc).
Back tension is irregular, or back
tension is too strong.
Back tension
Replace motor.
Clean motor pulley.
Motor shaft has undue run-out.
Motor pulley is oily and dusty.
Pulley has deflection. Replace take-up idler arm.
Pulley is stuck.
Take-up idler arm
No. 4151
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