Ericsson LBI-39055 , , ,

LBI-39055

❏ Send the LINE A input to the SPKR A output by

typing the following commands:

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:

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.