Polycom Vortex EF2241, Application Note

Page: 31 / 77

T
ESTING THE
A
UDIO
I
NPUTS AND
O
UTPUTS
1.
Go to S
YSTEM
I
NFO
, A
DMIN
S
ETUP
, P
HONE
A
UDIO
, and check the E
CHO
C
ANCELLER
option.
You must enable the codec's internal echo canceller in order for the audio meter
described in Step 2 to work properly.
2.
Go to S
YSTEM
I
NFO
, D
IAGNOSTICS
, A
UDIO
, A
UDIO
M
ETER
and then speak into one of the microphones.
Your level should be around 0 on the meter. You may also use the loop-back feature to listen to
your own audio in the local room. That feature is under S
YSTEM
I
NFO
, D
IAGNOSTICS
, N
EAR
E
ND
L
OOP
.
3.
Go to S
YSTEM
I
NFO
, D
IAGNOSTICS
, A
UDIO
, G
ENERATE
T
ONE
to listen to a codec-generated 1 kHz tone.
4.
Go to S
YSTEM
I
NFO
, A
DMIN
S
ETUP
, P
HONE
A
UDIO
, and un-check the E
CHO
C
ANCELLER
option.
W
IRING FROM
V
IEW
S
TATION
128 / H.323 / MP / 512
TO
V
ORTEX
D
EVICE
The inputs and outputs to most codecs are unbalanced. We recommend keeping the cable
from the Vortex device as short as possible to avoid any common-mode signals that may
corrupt the audio.
I
NPUT TO
V
IEW
S
TATION CODEC FROM
O
UTPUT OF
V
ORTEX
D
EVICE
Connect the Positive conductor of the Vortex device to the Tip of the RCA connector and the Negative
conductor of the Vortex device to Shield of the RCA connector.
The shield of the cable is not connected.
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