dbx 3BX III, Руководство по обслуживанию

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Model 3BX III Service Manual
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4.4 Impact-display adjustment
4.4.1 Set controls as follows:
Expansion Maximum
Impact Restoration
Middle
Transition Level Minimum
Pre/Post Pre
Source/Tape Source
Bypass
Out (i.e., not set)
4.4.2 Connect a clip lead from the junction of R704, R705, and D727
to ground. Short the inputs to ground.
4.4.3 Adjust VR724 so the first impact-restoration LED is just off.
Remove the clip lead.
4.5 Impact-release-rate control (initial adjustment)
4.5.1 Connect the dc voltmeter to the wiper of VR723 (the impact
release-rate control, on the rear panel).
4.5.2 Set VR723 so that the voltage measures -6.75 Vdc.
5. VCA-SYMMETRY ADJUSTMENTS
5.1 VCA-Symmetry Adjustment, Low Band, Left Channel
5.1.1 Set the controls as follows:
Expansion Minimum
Impact Restoration
Maximum
Transition Level Maximum
Pre/Post Pre
Source/Tape Source
Bypass
Out (i.e., not set)
5.1.2 Short the main inputs to ground and connect a sine-wave
oscillator to TP3 (U706L, pin 3). Set the oscillator for 100 Hz,
100 mV rms.
5.1.3 Connect the scope to the 3BX III left-channel output. Set
the vertical sensitivity to 20 mV/div and the horizontal to
2 ms/div.
5.1.4 Adjust VR701L for minimum signal feed-through; see Fig. 8.
Wrong Figure 8 Right
(Fig. 8, below)