Teac A-6300 - 13. MEASUREMENT AND ADJUSTMENT -ELECTRICAL- (A-6300); PLAYBACK HEAD, OUTPUT LEVEL, AND VU METER ADJUSTMENTS (A-6300)

13. MEASUREMENT AND ADJUSTMENT
-ELECTRIC AL-
ADJUSTMENT SEQUENCE
POWER SUPPLY CHECK AND ADJUSTMENT -
1. Place the power switch to the ON position.
2. Connect a VTVM across C-5.
3. Check the voltage at VR-1 and adjust for +24V DC.
PLAYBACK HEAD AZIMUTH ADJUSTMENT -
NOTE: After head replacement or if, during playback, a slight pressure
on the tape against the heads results in a higher indication
at the Test-Set (M-826A), head azimuth should be readjusted.
Coarse Adjustment:
1. Connect a Test-Set to either OUTPUT jack; remove the head Housing.
2. Thread a TEAC Test Tape YTT-1003 on the unit.
Play the 15 KHz Test Tone in Section 2 of the Test Tape.
3. Slowly rotate the azimuth screw until maximum indication
is obtained on the Test-Set.
4. Repeat the procedure in Reverse play mode for the Reverse play head.
Fine Adjustment:
NOTE: It is absolutely essential to accomplish the coarse
adjustment before performing the fine adjustment to avoid
phase errors larger than 45° After coarse adjustment, do
not make large corrections, turn azimuth screw 1/4 turn or
less.
5. Connect the test equipment as shown in Fig.11-1.
6. Play a 50 Hzn/10 kHz signal and adjust the azimuth screw
until the oscilloscope shows that the signals are less
than 45° out of phase (Forward and Reverse modes).
7. Secure the screw with a drop of Locking Paint.
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