Operating instructions

Digital Telephone Hybrid
Privacy Modes
The privacy switch on the TH3 can do three different things, based on the interface’s current privacy mode. The
three modes are, “mute tx only”, “mute rx only”, and “mute tx and rx”.
Supplementary Echo Canceller
The term “supplementary echo canceller” refers to any third-party acoustic echo canceller. Such a device may be
used to supplement the existing echo cancelling abilities of the TH3. Typically, an additional 5 dB of echo cancella-
tion may be achieved. In installations where very large amounts of microphone gain are required, a supplementary
echo canceller might significantly improve system performance.
SPECIFICATIONS
Technical Specifications
Power Input 300 mA (10W max.) at 20VAC
Expansion Jacks LecNet compatible, 8-pin mini-DIN, max. level +18dBu
RS-232 Port LecNet compatible, stereo mini phone jack, 9600 baud, 8 bits, no parity, 1 stop bit
Wired Remote Controls DB9F connector (see next section for pinout); max. LED current per pin 7mA
Aux 5-pin depluggable terminal block connector; electronically balanced output; nom. output
range -10 dBu to +4 dBu; max. output level +10 dBu; output impedance 200 ohms
balanced, 100 ohms unbalanced; nom. input range -10 dBu to +4 dBu; max. input level +10
dBu; input impedance 20K ohms balanced, 10K ohms unbalanced
Record Out 5-pin depluggable terminal block connector; electronically balanced output; max. mic level
-20dBu; max. line level +4dBu; nom. impedance 600 ohms balanced, 300 ohms
unbalanced; tape relay max. current 0.25A;
Supplementary Echo Canceller two 5-pin depluggable terminal block connectors; electronically balanced outputs; nom.
levels +4 dBu; input impedance 20K ohms balanced, 10K ohms unbalanced; output
impedance 200 ohms balanced, 100 ohms unbalanced
Codec Interface 5-pin depluggable terminal block connector; electronically balanced output; nom. output
range -10 dBu to +4 dBu; max. output level +10 dBu; output impedance 200 ohms
balanced, 100 ohms unbalanced; nom. input range -10 dBu to +4 dBu; max. input level +10
dBu; input impedance 20K ohms balanced, 10K ohms unbalanced; echo suppression 12 dB
to 24 dB in 1 dB steps; user receive volume -12dB to +6dB in 1 dB steps
Telephone Interface RJ11 modular connectors; compliant with FCC Part 68; impedance 600 ohms; auto answer
on ring count 1-10 if enabled; disconnect on calling party control signal if enabled; echo
suppression 12 dB to 24 dB in 1 dB steps; frequency response 300 Hz to 3500 Hz, +- 3dB;
THD (250 Hz to 3.3 KHz) less than .2%; user receive volume -12dB to +6dB in 1 dB steps
Physical Characteristics
Weight 4 lb.
Dimensions 19" wide x 1.75" high x 8" deep
(specifications subject to change without notice)
Pinout for Wired Remote Controls
54321
9876
VOLUME DOWN
VOLUME UP
PRIVACY
CONNECT
PRIVACY LED
CONNECT LED
Rio Rancho, NM – USA
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