Revision B • 7/00
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5
5 Maintenance & Alignment
nut so the knob can removed from the pot shaft.
Use a 7/16 inch nutdriver to remove the shaft nuts.
FADER SERVICING
There are no replaceable nor rebuildable parts
on the AirWave Digital fader assembly. Fader ser-
vice is comprised of cleaning and lubricating. All
faders are conductive plastic, single-element fad-
ers (PR&E # 90-1016) .
If the fader movement is rough, either the lubri-
cant on the glide rails has evaporated or foreign
material has gotten into the fader. Dow Corning
510 is the preferred glide rail lubricant as it will
not migrate to the contact fingers like other lubri-
cating oils.
Fader Disassembly and Cleaning
1.
Remove the module from the mainframe.
2.
Remove the circuit board from the faceplate,
per previous instructions.
3.
Remove the fader knob and the two fader
mounting screws, and then the fader from
the faceplate.
4.
Remove the snap-on fader assembly cover.
It is held in place by round stamped bosses
at each end. With the fader sitting label up
and the connector pins to the front, a pry-
point is on the right end of the fader cover.
5.
Clean the fader using only a dry cotton swab,
or a cotton swab wet with distilled water.
Note:
The use of chemical cleaners on the con-
ductive plastic will substantially shorten fader life.
Never touch the fader slider contact fingers while
cleaning the fader parts.
Use only a dry cotton swab, or a cotton swab
wet with distilled water, to clean the fader parts.
Always use a clean dry swab to dry off the con-
ductive plastic tracks after cleaning. If the fader
rails are noticeably dirty, wipe them off using a
dry cotton swab before lightly lubricating the top
rail with Dow Corning 510.
If coffee, a soft drink or other sugared liquid
has been spilled into the fader, remove it from the
module as soon as possible and remove the top
cover of the fader. Hold the fader under hot run-
ning water while moving the fader slider back and
forth to dissolve the sugars and other chemicals.
Thoroughly dry the rails and conductive plastic
using dry cotton swabs and then lubricate the top
fader rail with Dow Corning 510.
Lubricating the Glide Rail
Move the fader slider to the middle of its travel
and place one drop of Dow Corning 510 lubricant
on the top rail on either side of the fader slider
bushings. Move the slider through its full travel to
distribute the lubricant. Wipe off any excess lu-
bricant from the rubber stops at each end of the
glide rail. Normally only the top rail (the one the
fader slider bushings glide on) requires lubricant.
MICROPHONE PREAMP MODULE
The microphone trimpots are under a faceplate
security cover. They are set at the factory for a +4
dBu output level with a -55 dBu, 1 kHz input. In
the field, each trimpot can be adjusted for the spe-
cific microphone being used on that preamplifier.
ANALOG LINE INPUT MODULE
The Trim L and Trim R trimpots (R60 and R59)
set the left and right channel gain, respectively.
To adjust these trimpots:
1.
Set the fader at the -12 dB (nominal) mark
and assign the module to Program 1.
2.
Apply a 1 kHz signal at the nominal input
level for that channel (from -10 dBu up to
+4 dBu) to the left and right input connec-
tors. Either the A or B input can be used, as
the adjustment point is after the A/B switch.
3.
Using the Program 1 bargraph meters, ad-
just the trimpots for 0 VU (or -8 PPM).
