LBI-39055
23
❏
Send the
LINE A
input to the
SPKR A
output by
typing the following commands:
<F2>
6771
<Enter>
<F2>
7771
<Enter>
<F2>
8731
<Enter>
NOTE
If no headset is connected to the Audio Tower
the initial audio matrix switch settings will
route the
LINE A
input to the
SPKR A
output. Therefore, in this case, execution of
the above commands is not necessary.
❏
Verify the 1 kHz tone is heard in Speaker A.
CTEST's VU meter should indicate yellow.
❏
Adjust the select speaker (Speaker A) volume knob
up and down and verify the volume changes. This
knob is the left-most volume knob on the Volume
Controller Box.
❏
Turn the tone off by
typing the following
commands. The first command will turn it off:
<F2>
6770
<Enter>
<F2>
7770
<Enter>
<F2>
8730
<Enter>
Successful completion of this tests verifies basic
operation of the following:
•
Line A input circuitry
•
Speaker A power amplifier circuitry
•
PC and Logic Board's ability to control the cross-
point audio matrix switches on the Audio Matrix
Board
•
Volume Controller Box select volume control and
its related cabling
•
VU meter circuitry
2.
Send
LINE B
Input Audio to
SPEAKER B
❏
Remove the RJ-11 modular plug from the
LINE A
jack and connect it to the
LINE B
balanced input.
The balanced input is the two outside contacts on
the RJ-11 modular jack (yellow and black wires in
a modular cable).
❏
Verify the 1 kHz tone is heard in Speaker B. If
not, send the
LINE B
input to the
SPKR B
output
by typing the following command:
<F2>
6641
<Enter>
❏
Adjust the unselect speaker (Speaker B) volume
knob up and down and verify the volume changes.
❏
Turn the tone off by
typing the following
command:
<F2>
6640
<Enter>
Successful completion of this tests verifies basic
operation of the following:
•
Line B input circuitry
•
Speaker B power amplifier circuitry
•
PC and Logic Board's ability to control the cross-
point audio matrix switches on the Audio Matrix
Board
•
Volume Controller Box unselect volume control
and its related cabling
3.
Send Mic Audio To
LINE A
&
LINE B
Outputs
❏
If necessary, connect a headset to operator headset
jack box. Verify this jack box is connected to the
OPERATOR HEADSET
connector on the Audio
Matrix Board (#1).
❏
Terminate the Audio PA Board's (#1)
LINE A
balanced output terminals with a 600-ohm resistor.
The balanced output is the two center-most
contacts on the RJ-11 modular jack (red and green
wires in a modular cable). Connect an oscilloscope
across this load resistor.
❏
Send operator headset mic audio to the
LINE A
output by typing the following commands:
<F2>
6331
<Enter>
<F2>
1001
<Enter>
❏
Speak into the headset's mic and verify the audio
signal is present on the
LINE A
balanced output.
Maximum signal level is approximately 6 Vp-p.
❏
Turn the operator headset mic-to-
LINE A
audio off
by typing the following command:
<F2>
1000
<Enter>
❏
Verify mic audio is no longer on the
LINE A
balanced output.
❏
Move the
LINE A
balanced output 600-ohm
termination to the
LINE B
balanced output.
