Specifications

LBI-39062
4
OTHER INPUTS
MICROPHONE PTT AND MONITOR SWITCH Active-low inputs used to detect "dry-contact" switch closures
of the type found in standard microphones, footswitches and
headset jacks. Typical open-circuit voltage = 12 Vdc. Max.
open-circuit voltage = 16 Vdc. Max. short-circuit current =
30 mA.
MICROPHONE SENSE Active-low inputs used to sense the connection of a
microphone. Typical open-circuit voltage = 12 Vdc. Max.
open-circuit voltage = 16 Vdc. Max. short-circuit current =
30 mA
PAGE PTT Active-low input used to signal presence of paging signal on
paging audio input. Typical open-circuit voltage = 12 Vdc.
Max. open-circuit voltage = 16 Vdc. Max. short-circuit
current = 30 mA
AUDIO OUTPUTS
EARPHONES
Supervisor and Operator Headsets Outputs for two telephone-style headset earphones similar to
Plantronics model HS-0309-1. Typical output = 300 µW (-5
dBm) into 600 ohms. Max. output power before limiting =
3.5 mW (+5 dBm) into 600 ohms.
SPEAKERS
Select and Unselect(s) Audio power amplifier differential outputs designed to drive
3.2 to 16-ohm speakers. Max. output power selectable to 5 or
8 watts (minimum) into 8 ohms at full volume. Max. number
of unselect speakers = 3.
LINE A, B, C & D Balanced 2-wire 600-ohm outputs each designed to transmit
voice bandwidth audio to one pair of a 4-wire 600-ohm
twisted-pair transmission system provided by the CEC/IMC.
Capacitively coupled and transformer isolated. Typical output
= -5 dBm. Output range = -20 to +10 dBm.
CALL DIRECTOR PATCH (LINE D) Balanaced 600-ohm output designed to deliver audio to a Call
Director device similar to Plant Equipment model 3780-L1-
TT-010. Typical output = -5 dBm. Output range = -20 to 0
dBm.
SELECT & UNSELECT RECORDERS Unbalanced 600-ohm outputs each designed to drive audio
inputs of an external recording device. Capacitively coupled.
Typical output = -5 dBm. Output range = -20 to +2 dBm.
RELAY CONTACT OUTPUTS Form-A (SPST normally-open dry contacts) relay connections
isolated from ground and all other signals. One relay activates
on console PTTs. Two others are activated via reserved
keystrokes at the Dispatch Keyboard. Contact rating = 0.75
amps at 26 Vdc. Ground isolation = 500 Vrms (60 Hz). Open
contact isolation = 500 Vrms (60 Hz).
*
These specifications are intended primarily for the use of the serviceman. See the appropriate Specifications Sheet for complete specifications.
CREDITS
IBM is a registered trademark of International Business Machines Corporation.
PC-AT is a trademark of International Business Machines Corporation.
MS-DOS is a registered trademark of Microsoft Corporation.