Mechanical Checks and Adjustments
Model C 1102
Note:
All the mechanical checks and alignments should be
done with the upper and bottom cabinet assembly (A-1 and A-
2) removed.
Take-up Torque
(Spec. 30-60 g/cm)
1.
Load the torque meter cassette.
2.
Set the unit in the play mode and read the value on the dial
scale. The meter should indicate a torque of 30 to 60 g/cm.
3.
If the torque range is out of the specified limit, clean the
driving surface of the take-up reel base shaft assembly (B
1-8) and tape-up pulley assembly (B 1-12) with pure
alcohol.
4.
If the above cleaning proves ineffective for a correct tor
que alignment, replace the take-up reel base shaft as
sembly.
5.
First, remove the reel table assembly (B 1-12), then pull
out the take-up reel base shaft assembly. After putting a
drop of oil on the reel shaft (B 1-17), insert the new part
and then fit the reel assembly onto it's shaft. Finally tighten
two set screws (L 1-1).
Fast-Forward and Rewind Torque
(Spec. 65-120 g/cm)
1. Load the torque meter cassette.
2. Set the unit at F.F. or REWIND mode and read the value on
the dial scale. The meter should indicate a torque of 65 to
120 g/cm.
3. If the value is outside the specified range, clean the driving
surface of the fast forward pulley A assembly (B 1-14), fast
forward pulley B (B 1-13) and C (B 1-14).
4. If the above cleaning operation is ineffective for a torque
alignment replace the fast forward pulley A assembly.
5. To replace, first remove the fast forward and rewind arm A
assembly (B 1-29).
1. Place the unit in the play mode (but without a loaded tape).
2. Attach the spring scale to the edge of the pinch roller as
sembly (B 1-18) as shown (fig. 1).
3. Gently draw the pinch roller assembly away from the capstan
shaft (in a direction parallel to a line that inter cepts the
centre of the capstan shaft and the pinch roller) until the
capstan shaft and the pinch roller are completely separated.
4. Gradually lessen the pressure until the pinch roller just begins
to rotate. The scale should then read approximately 500-650
g/cm.
5. If the scale reading is outside the above range, replace the
pinch roller spring (B 1-61) or adjust the spring arm as shown.
6. After the replacement, install the pinch roller adjusting nut (B
1-87) with 1 mm vertical clearance. Check whether the pinch
roller is vertical to the capstan.
Tape Speed / WOW and Flutter
Note:
Before commencing the following alignments, make
sure that all parts in the tape path, particularly the capstan,
pinch roller and head, are cleaned with pure alcohol.
1. Connect the AC vacuum tube voltage meter to both chan
nels of the "Line-out".
2. Use a test tape (in which 10,000 Hz signal is recorded).
3. To achieve the maximum reading on the AC VTVM adjust the
azimuth alignment screw (fig. 2).
4. After the adjustment, fix the screw with lacquer.
Tape Speed
(Spec. 3000 Hz ± 45 Hz)
1. Connect the frequency counter to both channels of the line-
out.
2. Set the EQ switch to normal position, then load and play a
TEAC MTT-111 test tape in which a 3000 Hz signal is
recorded.
3. Adjust the control located at the top of the meter for a reading
of 3000 Hz ± 5 Hz on the frequency counter (fig. 3). (This
tape speed alignment should be done after approx. 30
seconds operating time).
4. Then, verify the reading on the frequency counter as being
within the specified range 3000 Hz±45 Hz at the beginning,
middle and near the end of the tape.
Wow and Flutter
(Spec. DIN weighted: within ± 0.2% at record and playback)
Note: When using these methods, obtain the maximum wow and
flutter value, by repeated play, stop or pause mode of operation.
This operation ls necessary to make sure that the wow and
flutter value between record and playback will not create a false
reading.
1. Connect the oscillator to the line-in of the unit, and the wow
and flutter meter to either channel of the line-out.
2. Set line or record controls of the unit to obtain the optimum
input level.
3. Load a test tape (BASF C 60) and set the BASF/EQ
switches to the normal position.
4. Apply and record a 3000 Hz signal.
5. Record and play the recorded section.
6. Read the value on the wow and flutter meter. The wow and
flutter value should be within ± 0.2 %, DIN max.
7. If the measured value is out of specification, check the take-
up torque and pinch roller pressure, and see that the capstan
or belt is not stretched or oily.
8. If the above checks prove ineffective, repair or replace the
pinch roller assembly (B 1-6), motor and any other defective
parts.
9. When the capstan assembly must be replaced, make sure it
is weil oiled. Re-adjust the end clearance by adjusting the
thrust-screw (B 1-111) until the clearance is between 0.15-0.3
mm.
