Telos Zephyr, User Manual

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Section 4 INSTALLATION & BASIC OPERATION
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Zephyr Xmt-To-Rcv Mode Compatibility Table
This table shows which Zephyr Xmt and Rcv modes may operate with each other, the
resulting audio bandwidth for each, and information which describes what happens to
the audio channels when they are output from the decoder.
Xmt Mode Rcv Mode Audio Resp. Notes:
L3 DUAL (one Line)
(Channel A) L3 MONO
(Line 1) 15/20kHz* Audio appears on both
outputs.
L3 DUAL (two Lines to
two sites) L3 MONO
(Line 1) 15/20kHz* Audio appears on both
outputs at both sites.
L3 DUAL (two Lines to
one site) L3 STEREO 15/20kHz* Audio output channels
correspond to input.
L3 JSTEREO or L3
STEREO L3 STEREO 15/20kHz* Audio output channels
correspond to input.
L2 MONO (Channel
A) L2 7.8/9.8kHz** Audio appears on both
outputs.
L2 MONO128
(Channel A) L2 20kHz Audio appears on both
outputs.
L2 JSTEREO L2 20kHz Audio output channels
correspond to input.
L2 DUAL L2 7.8/9.8kHz** Audio output channels
correspond to input.
L2 HALF/24 L2 HALF/24 8.6 kHz Audio appears on both
outputs.
G.722 G.722 7kHz Audio output corresponds
to Line connection.
* Depending upon sampling rate: 15kHz at 32 kHz; 20kHz at 48 kHz.
** Depending upon bitrate: 8kHz at 56kbps; 11kHz at 64kbps.
As well, both transmission bitrate and audio sampling rate must correspond in order for
operation to occur.
DEALING WITH DELAY
Mix-Minus
All perceptual coders have too much delay for talent on remote to hear themselves via a
round- trip loop. Therefore, a special
mix- minus arrangement is required – exactly the
same as has been used with satellite linked remotes for years.
The principle is this: The remote talent does not hear himself via the studio cue return.
Rather, his microphone is mixed locally with a studio feed which has everything
but the