Teac A-300 - Mechanical Checks and Adjustments (Continued); Tape Speed, Wow, and Flutter Adjustments

5-4. TAPE SPEED/WOW AND FLUTTER
Specifications:
Tape Speed Deviation: 3,000 Hz+ 45 Hz
Tape Speed Drift: 45 Hz
Wow and Flutter: Playback: 0.10% (WRMS)
Record/Playback:
0.25% (RMS)
NOTE: 1. Before performing this adjustment, clean all
parts in the tape path, particularly the Capstan,
the Pinch Roller and the Heads with the appro-
priate liquid from the TEAC TZ-261 Cleaner
Kit or with pure alcohol.
2. Wow and flutter should be checked in two
ways; Playback only and Record/Playback
methods. First correct tape speed and wow and
flutter using the playback only method. Then
measure wow and flutter using record and play-
back method.
3. As the measured results may vary with respect
to location on tape at which it was taken, three
points — at beginning, middle and near the end
of the tape — should be measured.
54-1. TAPE SPEED
1. Connect test equipment to the deck, except the AF
oscillator, as shown in Fig. 5-3.
2. Set the EQ switch to NORMAL position, and then load
and play a TEAC MTT-111 test tape (3,000 Hz signal
is recorded),
3. Adjust the control located at the center of the Motor
for reading of 3,000 Hz + 10 Hz on the frequency
counter,
(NOTE: This tape speed setting should be done after
approx, 30 seconds of operating time of the deck).
4. Then, verify the reading on the frequency counter as
within the specified range of 3,000 Hz + 45 Hz, and
the tape speed drift is within 45 Hz at any portion of
the tape run.
5. If the tape speed is extremely out of the specification,
check the Pinch Roller pressure and the tape driving
function for correction, and make sure the tape path
is clean.
5-4-2, WOW AND FLUTTER
After making the tape speed measurement, perform the
wow and flutter test using the Playback Method and the
Record /Playback Method successively.
PLAYBACK METHOD
1. Play the MTT-111 test tape.
2. Read the indication on the wow and flutter meter.
3. The wow and flutter value should be 0.10% WRMS,
max.
10
FREQUENCY COUNTER
wow & FLUTTER METER
DECK
under TEST ¢
+463
Fig. 5-3 Tape Speed/Wow & Flutter Measurement Setup
,
TAPE SPEED ADJ. ¥
f 3,000Hz + 10Hz
OA aude wr
T-1679
Fig. 5-4 Tape Speed Adjustment Location
4. If the wow and flutter is out of specification, check the
Pinch Roller pressure and the take-up torque, see that
the tape path is clean, and that the Capstan Belt is not
stretched or oily.
5. If the above checks are ineffective for excessive wow
and flutter correction, repair or replace the Pinch
Roller, the Capstan Belt and/or any other defective
parts.
RECORD/PLAYBACK METHOD
NOTE: When using this method, adopt the maximum wow
and flutter value obtained by repeated play and
stop modes of operation. This operation is neces-
sary to make sure wow and flutter content be-
tween record and playback will not be in phase to
create a false reading.
1. Connect test equipment to the deck as shown in Fig.
5-3.
2. Set LINE or RECORD controls on the deck to obtain
convenient input levels.
3.
Load
a
TEAC
MTT-SO1
test
tape
(blank)
and
set
the
BIAS/EQ switches in the NORMAL positions.
Apply and record a 3,000 Hz signal.
Rewind and play this recorded section.
Read the indication on the wow and flutter meter.
The wow and flutter value should be 0.25% RMS max.
If the measured value is. out of specification, repair
using the same methods as stated in steps 4 — 5 in the
Playback Method procedure.
On Nn