Teac A-2300SD - Frequency Response-Playback-; Phone Output Check; Monitor Level Setting; Specified Input Level Setting

9-7 FREQUENCY RESPONSE-PLAYBACK-
1. Place Tape SPEED SW in 7-1/2 ips (HIGH) position.
2. Thread a TEAC Test Tape YTT-1003 on the unit.
3. Compare the readings obtained on the Test-Set (VTVM)
with the Response Limits given in Fig. 9-6.
4. if adjustment is required, adjust VR-102/106 for HIGH
speed.
5. Change Tape SPEED SW to 3-3/4 ips (LOW) position.
6. Thread aTestTape YTT-1002 on the unit.
7. Repeat Step 3. Check for freq. response.
8. If adjustment is required, adjust play EQ VR-103/
107 for LOW speed.
NOTE: If the frequency response does not meet
specified response limits, especially at the high-
end of the spectrum, head should be checked
for accumulated dirt or oxides. If clean, head
azimuth must be readjusted.
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Fig. 9-6 Frequency Response - Playback -
9-8 PHONE OUTPUT CHECK
1. Place OUTPUT control at the SPECIFIED level setting
(400 Hz/0 dB).
2. Connect an 8S2 non-inductive resistor across the head¬
phone jacks. Connect VTVM or Equivalent across
the resistor.
3. VTVM should indicate —24 dB ±2 dB. (4 9 mV).
9-10SPECIFIED INPUT LEVEL SETTING
1. Apply a 400 Hz signal at-8 dB (308 mV) to the LINE
IN jacks.
2. Adjust both LINE Controls simultaneously for 0 dB
at OUTPUT jacks. If both channels do not read 0 dB
at the same position of the LINE Controls, set the
LINE Controls so that the higher reading channel
reads 0 dB. Then adjust VR-104 or VR-108 so that
the lower channel reads 0 dB.
NOTE: At this point both the LINE Controls and the
OUTPUT Controls are at the “Specified set¬
ting”. Do not move these controls unless
instructed in this procedure to do so. The
accuracy of many of the following adjust¬
ments and readings depends on these controls
being at the “Specified setting”.
9-11 VU METER LEVEL CHECK
3. With controls set as described above, check for 0 VU
indication on the VU Meters.
9-12 CAL TONE LEVEL ADJUSTMENT
With controls set as described above in MONITOR LEVEL
SETTING:
1. Place the CAL TONE SW on fhe back panel to the IN
position.
2. Adjust VR-403 for 0 VU on the VU Meter.
3. If readings between channels are different, balance the
readings around 0 VU.
NOTE: The following checks and adjustments must be
performed with the CAL TONE SW in the
OFF position.
9-13 MIC INPUT LEVEL CHECK
This is check only. No adjustment are to be made.
9-9 MONITOR LEVEL SETTING
1. Connect an AF oscillator to the LINE IN jacks.
2. Place MONITOR SW in SOURCE position.
3. Apply a 400 Hz signal —18 dB (97 mV) to the LINE IN
jacks.
4. Turn LINE control fully clockwise.
5. Adjust VR-104/108 for 580 mV (-2.5 dB) at
the DOLBY ENCODER Test Points (39, 49).
6. Check for 0 dB (775 mV) at the OUTPUT jacks.
1. Set MIC controls fully clockwise.
2. Apply a 400 Hz signal at -70 dB to the MIC input
jacks.
3. Check for 0 dB level at OUTPUT jacks.
4. With 0 dB at OUTPUT jacks, MIC input level should be
-70 dB ±2 dB.
5. Return MIC controls fully counter clockwise to prevent
noise insertion during following steps.
9-14 MPX FILTER RESPONSE CHECK
1. Apply a 19 kHz, -8 dB signal to the LINE IN jacks.
2. Place the DOLBY FM SW to IN position.
The level indication on the VTVM should decline by
30 dB or more with the DOLBY FM SW IN compared
to the level with the DOLBY FM SW to OUT.