JVC D-M3 - Page 10

D-M3 A/B/C/E/J/U
Item Adjustment Adjusting sioncatd a Remarks
: point value
Adjusting erase Turn the screw © for aligning the erase | Screw (C) Be sure to perform this adjustment
head height head until it stops. Then, turn the screw in (D) after replacing the erase head.
the reverse direction by 1.5 revolution. —
Employ a special cassette (MC-60) from
which parts of the casing, where the erase Incorrect
head, record/playback head and capstan Correct Tape guide
engage, has been cut away. Perform tape Tape guide Tape
transport with the cassette tape. Adjust Er Tapeguide
the screw © until the tape runs in the a
center of the erase head tape guide. Tape
Adjusting motor Connect a speed meter (an electronic | Semi-fixed 3000 Hz If the speed meter functions as a
speed counter) to the LINE OUT terminals. resistor in wow and flutter meter, also, connect
Playback the OA-W212 (2.4 cm/s) or OA- | the motor the deck to the INPUT terminals of
W221 (1.2 cm/s) test tape. the meter.
Adjust the semi-fixed resistor in the motor
until the reading of the speed meter is
3000 Hz.
Checking Employ a torque testing cassette tape
playback torque (TW-112A) for the checking.
7~15 gr/cm If the standard torque is not obtain-
ed, replace the take-up disc
assembly.
Checking fast Measure the torque in the fast forward More than If the standard torque is not Bbtane|
forward torque mode in the same manner as in the above 40 gr/cm ed, perform the following.
(TW-1231A). 1.Clean the capstan belt, the motor
pulley, the take-up reel disc cir-
cumference, the flywheel cir-
cumference, etc.
2. Replace the belt.
Checking rewind
Torque
More than
40 gr/cm
Measure the torque in the rewind mode in
the same manner as in the above.
Connect a wow and flutter meter to LINE
Checking wow
and flutter OUT terminals.
Playback the OA-W212 or OA-W221 test
tape.
Check to see if the reading of the meter is
within 0.12% (WRMS) — 2.4 cm/s or
0.40% (WRMS) — 1.2 cm/s
ae
Checking music 1. After pushing CUE or REV button, playback the TMT-6438 test tape at music scan mode. Check to do music
scan scanning.
2. Using the TMT-6439, the music scan mechanism does not function.
No. 4213
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