dbx 3BX III, Руководство по обслуживанию

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Model 3BX III Service Manual
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5.2 VCA-Symmetry Adjustment, Mid-Band, Left Channel
Follow the procedure in 5.1 but go to TP5 and VR702L.
5.3 VCA-Symmetry Adjustment, High Band, Left Channel
Again follow the procedure in 5.1 but go to TP7 and VR703L.
5.4 VCA-Symmetry Adjustment, Low band, Right Channel
Follow the procedure in 5.1 but go to TP4 and VR701R and change
outputs (left to right).
5.5 VCA-Symmetry Adjustment, Mid-Band, Right Channel
Follow the procedure in 5.4 but go to TP6 and VR702R.
5.6 VCA-Symmetry Adjustment, High Band, Right Channel
Follow the procedure in 5.4 but go to TP8 and VR703R.
6. VCA-GAIN ADJUSTMENTS
6.1 Set the controls as in 5.1.1
6.2 Connect the sine-wave oscillator to the left and right inputs of the
3BX III.
6.3 Left-Channel Adjustment
6.3.1 Set the oscillator for 100 Hz at 0 dBV (1 V rms) ±0.1 dB.
6.3.2 Connect the left-channel output of the 3BX III to an AC
voltmeter.
6.3.3 Adjust VR717 for unity gain, i.e., an output of 0 dBV (1 V
rms) ±0.1 dB.
6.3.4 Set the oscillator for 1 kHz at 0 dBV (1 V rms) ±0.1 dB.
6.3.5 Adjust VR719 for unity gain.
6.3.6 Set the oscillator for 10 kHz at 0 dBV (1 V rms) ±0.1 dB.
6.3.7 Adjust VR721 for unity gain.
6.4 Right-Channel Adjustment
Repeat 6.3 above, but observe the right-channel output and make the
unity-gain adjustments at VR718 (at 100 Hz), VR720 (at 1 kHz), and
VR722 (at 10 kHz).
6.5 Verify that the gains have been set correctly by sweeping the
oscillator from 20 Hz to 20 kHz and observing the output amplitude vs.
frequency of both channels. It should be ±0.5 dB.