RTS CS9500, Руководство пользователя

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I
considerable experience in this area. Please
call
with
requests and unusual applications.
5.X: The "Dallas" Version.
Developed in response to the very bad phone line conditions which
exist
in the Worth and areas.
For some reason, these parts of the country have exceptionally bad
phone service. Levels
vary over a
30
-
dB range and line
impedances are particularly difficult for the hybrid to
accommodate. This version adds more ducking in both directions,
increases the
action, lowers the receive expansion threshold,
.
and alters the adaptive hybrid parameters to effect better trade-
offs for bad phone
lines.
Outside of Dallas,
this
is for people who:
1)
Prefer a more of "speakerphone"
switching
effect.
2) Prefer a more aggressive AGC action on the phone audio.
3)
Need to accommodate very poor phone
lines
with widely
4)
Have
open
monitor speakers and
are
having trouble with
varying levels.
feedback
When
the phone line impedance
is
very complex. The Telos
hybrid then leaks too much during
send
audio, causing the
digital hybrid to halt adaption. Version 5.x software can tolerate
more leakage, due to a change
in one
of the adaption parameters.
Secondly, a "see-saw" ducking effect has been added. That
is,
the
ducking
occurs
on the send path during receive and on the receive
path during send. The level of the ducking is about 15 dB, yet it
has a very fast recovery time and
is biased more toward the
receive side. The full-duplex operation
is
not affected, just the
level of the ducking (about
6
d B with standard software). The
expansion threshold level has been reduced so lower-level callers
don't get expanded down.
this,
along with Telos' digital pitch
shifter and digital AGC helps the hybrid adapt better to poor
phone
lines.
6.X: "RTS Version"
This
is
the preferred version for connecting
RTS
or other 2-wire
intercom system
to
the Telos
ONE
phone jack. Stays on
continuously. A change
in
the adapt threshold allows send level
to be increased with a resistor for RTS operation.