Operating instructions

OPTIMOD-AM DIGITAL MAINTENANCE
4-7
See the assembly drawings in Section 6 for component locations. Be sure to turn the
power off before removing or installing circuit boards.
Follow these instructions in order without skipping steps.
Note: To obtain an unbalanced output, jumper pin 1 (ground) to pin 3, and measure
between pin 1 (ground) and pin 2 (hot).
Note: All analog output measurements are taken with a 620 ±5% resistor tied be-
tween pin 2 and 3 of the XLR connector.
1. Prepare the unit.
A) Set the GND
LIFT switch to the earth ground symbol setting (left position) to
connect chassis ground to circuit ground.
B) Use the front panel controls to set the 9400's software controls to their de-
fault settings, as follows:
a) Navigate to S
ETUP > IO CALIB > ANLG IN CALIB. After writing down the old
settings (so you can restore them later), set controls as follows:
Input ............................................................................................. analog
AI Ref VU ................................................................................... +4.0 dBu
R CH BAL.........................................................................................0.0 dB
b) Navigate to S
ETUP > IO CALIB > DIG IN CALIB. Set controls as in the table
below:
DI Ref VU ................................................................................ –15.0 dBFS
R CH BAL.........................................................................................0.0 dB
c) Navigate to S
ETUP > IO CALIB > ANLG OUT CALIB. Set controls as follows:
AO #1 100% ............................................................................ +10.0 dBu
AO #1 OUTPUT......................................................................Analog AM
AO #2 100% ............................................................................ +10.0 dBu
AO #2 OUTPUT......................................................................Analog AM
d) Navigate to S
ETUP > IO CALIB > DIG OUT CALIB. Set controls as follows, using
the N
EXT button to access controls as necessary.:
DO #1 100% ............................................................................. –2.8 dBFS
DO #1 RATE ...................................................................................32 kHz
DO #1 SYNC.................................................................................internal
DO #1 Word Len .................................................................................. 20
DO #1 Dither ......................................................................................Out
DO #1 FORMAT................................................................................AES3
DO #2 100% ............................................................................. –2.8 dBFS
DO #2 RATE ...................................................................................32 kHz
DO #2 SYNC.................................................................................internal
DO #2 Word Len .................................................................................. 20
DO #2 Dither ......................................................................................Out