dbx 3BX III, Руководство по обслуживанию

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Model 3BX III Service Manual
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NOTES
Miscellaneous notes on servicing the dbx 3bx III Audio Expander
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Removing the control knobs
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Remove the case top.
Unplug the 5 LED connectors from the right hand side of the front panel.
Using a 1.5mm hex ball driver, untighten the Allen screws holding each knob to
the shafts.
(Note: for the right-most knob, you’ll need to align the grub screw with the
hole in the metal shield surrounding the pot shaft.)
Pull the knobs out from the front panel, taking care not to lose the plastic
‘grommet’.
Audible hum
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If the unit produces audible hum in the output, it’s likely that some of the
power supply filter capacitors have dried out or leaked. It is recommended you
replace all 4 capacitors, even if some seem OK, since they’re all of a similar
age and likely to go the same way if not already. You’ll need 4 capacitors
470uF/35V with radial leads on 5mm pitch. If any of the capacitors have leaked
electrolyte, take care to clean all traces of corrosion from the PCB and its
components. A mild ammonia solution will assist in dissolving copper sulphate
(blueish) residues, followed by distilled water washing and thorough drying.
Daniel Ford
15 January 2006