Wheatstone D-8000, Technical Manual

Page: 64 / 169

page 8 – 4
D-8000 / Jan 2003
C P U & D S P M O D U L E S
the mode you normally want the port to operate in. This ability to switch the
port mode is useful in a system where the console is normally connected to
the Wheatstone Bridge 2001 via an RS-485 link, and the necessity arises to
reconfigure a channel using VDip on a computer with an RS-232 port.
Assuming that you’re provided wiring from both the RS-232 and RS-485
outputs of COM1, all you then need to do to switch between router operation
and VDip is to press the recessed switch. Press it again to toggle back to the
original mode.
3. The third function is nominal audio make-up gain. DIP switch
SW-5 is used to establish the master gain setting for the D-8000 console.
This allows users to configure the nominal fader setting and signal head-
room to suit their specific needs or preferences. The digital audio signals
entering the D-8000 console are usually normalized in the recording or
transmitting process for peak signals such that the absolute maximum peak
signal is very close to, but does not exceed, the maximum or highest digital
word in the AES bit stream. This implies that any decrease in signal caused
by placing the console fader at a “normal” setting somewhat less than full
up needs to be made up at the output of the console or the signal will be lower
than it was at the source. Radio consoles are normally operated with their
faders at less than full up to allow for some control over level and mixing
(if a signal is too low or quiet, the fader can be moved up until the signal
matches the normal levels as shown in the console meters.). By using the DIP
switches, the user can configure what the normal fader setting (and hence the
output make-up gain) should be. Consult the “Global Gain” table in the
“Internal Programming Options” section, page 8-9, for the gain values. The
D-8000 console is normally shipped with a make-up gain setting of +12dB
for a nominal fader setting of -12dB from the top. The gain value briefly
shows in the CPU display window during the console power up process
(“12--00dB” ind12dB gain). Note that setting the make-up gain too
high for the signals and fader settings used can result in a clipped or distorted
signal, just as it could with an analog console.
4. The fourth function is the CPU display window. The eight characters
displayed in this window are used to communicate general information to
the user. During the power up process, the CPU tests each module for proper
communications; any errors found will be displayed in the CPU display
window. Once the module communications have been tested, the CPU
briefly shows the selected make-up gain (see above), and then displays
<PRESETXX>, where XX indicates the current console preset number
(01 - 99). Pressing the “Preset Select Knob” alternately displays
“REMOTE <>” and “REMOTE><“ to indicate normal operation (if the
console has been fitted with the optional EQ controller the display alternates
between “REMOTE /\” and “REMOTE \/” indicating correct communica-
tions with the EQ controller). If the CPU detects an error during normal
operations, it will show the error message in the display window. If you see
such a message, make a note of it and contact Wheatstone Technical Support
for instructions. Note that the alternate display is changed to “LOCAL <>”
and “LOCAL ><“ (or “LOCAL /\” and “LOCAL \/” in the case of EQ
controller versions) when the console serial interface has been de-activated
by pressing the large red button on the CPU module.
D-8000 / Jan 2004