Telos Zephyr, User Manual

Page: 79 / 258

Section 4 INSTALLATION &
BASIC OP
79
It is preferable (for maximum audio quality) to use 64kbps when possible, but it is not
always possible owing to the limitations of some Telco digital connection paths. 56kbps
works more universally, so it is the value we’ll use here:
Xmt L3 STEREO
Rcv L3 MONO
Rate [56kbps 32kHz]
<NO> options
The second value, here 32kHz, is the audio sampling rate. It must be set to match the
value of the unit at the other end. More information about choosing the appropriate
sampling rate is in section 7 (Audio Coding Principles).
Dual Site Operation
It is possible to use the dual mono transmit mode to send to two receivers at different
sites. Set the transmit mode to
L3 DUAL
and dial Line 1 at each site.
This topic is covered more thoroughly in section 8 (Detailed Menu Reference).
Receive, if used, must be set to the G.722 mode. The Layer II/III decoders are unable to
accommodate the independent signals.
ISDN TIP!
With the internal ISDN interface, the rate value is used both to
set the Zephyr coder/decoder parameters and to tell the ISDN
network what rate to use during call setup.
Rate adaptation for the Bit Rate is automatically used on the
ISDN channel. Further, when a call is answered at the Zephyr,
the bit rate value is updated to properly reflect the ISDN
network condition.
COMPATIBILITY TIP!
On the Zephyr, we refer to the per-line bitrate. In the stereo
modes, the total bitrate is two times this number. This can be
confusing because some other codecs use the total, rather
than the per-line value.
IMPORTANT!
You must make the call to the telephone number for Line 1, as
the mono L II/III decoder will only work with a signal coming
from the first line.