Electronic Phone Systems
This tutorial introduction to electronic phone systems may be
helpful
if
you desire to
a Telos hybrid to such systems.
The cable from the phone
sets
to the "common equipment" must
convey:
Power to operate the phone
A
two-way data path
The speech audio path
The early electronic phones used a separate pair for each of the
three
functions, and thus required
six
wires. The
Horizon
was an example of
this
approach. Another
is
the popular Merlin
system which
uses
four pairs.
The most common approach
used
in new designs
is
a two pair, four-
wire scheme. In
this
scheme, the talk and data are each balanced
and each use one of the
two
pairs. The power is "phantom"
applied between the two pairs in a way similar to the method
used for phantom powering condenser microphones
in
recording
studios.
to
power
phone
Audio in
Audio to Set
Electronic Phone Scheme Using
Two
Pairs
-
Note
this diagram
shows
flow
in
one direction for
A
transformer
is
generally used at each end of the audio pair
that the phantom power
may
be added. The data pair often
uses
resistors to obtain a "center tap" rather than transformers since the
data signal has
components that would not pass through a
transformer.
ON€
ELECTRONIC PHONE TUTORIAL
Summary of Contents for CS9500
Page 16: ...Telos ONE plus ONE Dual Digital Telephone Interface User s Manual 1 1 I...
Page 21: ...SECTION 1 INTRODUCTION...
Page 27: ...INSTALLATION SECTION 2...
Page 28: ...8 T IOS ONEPIUS ONE INSTALLATION...
Page 35: ...OPERATION SECTION 3...
Page 53: ...DRAWINGS SECTION 5 Te ONEplusONE DRAWINGS 35...
Page 56: ...F Telos ONE PLUS ONE TMS320C25 Pinouts...
Page 57: ......
Page 59: ...J1 4 1 I 0 2 e J6 0 5 P1 IN LVL Telos ONE PLUSONE input output audio...
Page 60: ...e J3 e HDRl 5v f DATA LINES 0 7 Tela ONE PLUSONE phone control...
Page 61: ...APPENDIX SECTION 6...
Page 70: ...wl 1 lo I1 I d f r r 1 J...
Page 71: ...Accessory PCB Module BASIC AUTO ANSWER BOARD TeksONEplus ONE BASICAUTO ANSWER BOARD...
Page 74: ...Telos basic AutoAns Rev 3 1...
Page 75: ...Accessory PCB Module SUPER AUTO ANSWER BOARD TelosONEplusONE SUPER AUTO ANSWER BOARD...
Page 89: ...c...
Page 90: ......
Page 91: ......
Page 92: ...t Tutorial ELECTRONIC PHONE SYSTEMS TebsONEplus ONE ELECTRONICPHONETUTORIAL...