Operating instructions

Digital Telephone Hybrid
BRIEF TECHNICAL DESCRIPTION
The TH3 provides a high-quality, flexible and powerful interface to a telephone line, a 4-wire video codec, or both
simultaneously with bridging. Each interface offers basic controls to connect, invoke privacy (selective mute), and
perform fine adjustments to the receive volume. The basic controls are available from the front panel, the wired
remote controls, and via the serial port. Using the serial port, additional features may be controlled, such as echo
suppression settings, telephone receive AGC, auto answer and auto disconnect, DTMF dialing and specialized signal
routing.
LINE ECHO
CANCEL
PHONE
INTERFACE
ECHO
SUPPRESSION
CODEC
INTERFACE
ECHO
SUPPRESSION
"TELEPHONE
RX LEVEL"
"CODEC TX TRIM"
"CODEC RX LEVEL"
AUX PORT
MAIN IN
MIX- IN
MAIN OUT
MIX- OUT
SIG IN
SIG OUT
SIG TOTAL
log
"LECNET ANTI-ECHO"
EXPANSION
PORTS
RECORD
OUT
LINE/MIC
SWITCH
"FINE LEVEL"
"LECNET ANTI-ECHO"
"OUTPUT LEVEL"
"TX LEVEL"
AGC
RX BUS
"RX LEVEL"
"TX LEVEL"
TX BUS
"MAIN IN"
"MIX MINUS IN"
"MAIN OUT"
"MIX MINUS OUT"
"AUX INPUT"
"EXPANSION PORT"
(SOFT)
(SOFT)
(SOFT)
"COARSE LEVEL"
TH3 Block Diagram
Rio Rancho, NM – USA
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