360 Systems DigiCart/EX - Manual (Page 83)

E LECTRICAL S PECIFICATION FOR D-N ET T RANSFERS
File transfers may be accomplished via either of two digital audio interfaces:
• AES-3id-2000 (AES standard, 75Ω impedance, BNC connector)
• AES-3 (AES standard, 110Ω impedance, XLR connector)
Both outputs always carry the same signal. There is no output selection necessary.
AES-3ID
The AES-3id-2000 interface has been designed to operate using coaxial cable with a nominal
impedance of 75Ω with a male BNC. DigiCart/EX does not terminate this signal internally.
When a coax cable is connected from a DigiCart II output to the input of a DigiCart/EX, a 75Ω
termination must be added at the receiver end of the line (DigiCart/EX). This can be done with a
T-connector and terminating cap. If DigiCart II is the receiving end, do not use external
termination.
If other devices are inserted in the data path (such as routers or switchers), the user should
ensure that the transmitting DigiCart drives a nominal impedance of 75Ω and that the receiving
DigiCart is being driven by an output presenting a nominal 75Ω output impedance. This will
serve to maintain correct signal amplitude and to minimize transmission errors caused by signal
reflections from the far end of the cable.
The AES-3id-2000 interface has been successfully tested using 150m of Belden 8281, 75Ω
coaxial cable.
AES-3
The AES-3 interface has been designed in compliance with the AES-3 recommended practice for
serial transmission format for two-channel digital audio data. The connectors required for this
interface are described in IEC 268-12, and are XLR three-pin connectors. The pin usage is:
PIN 1: CABLE SHIELD OR SIGNAL EARTH
PIN 2: SIGNAL
PIN 3: SIGNAL
Note: The polarity of pins 2 and 3 is not significant.
The recommended cable for use with AES-3 is balanced and shielded with a nominal
impedance of 110Ω at frequencies from 0.1 to 6.0 MHz. The maximum recommended cable
run for file transfer using AES-3 is 100 meters.
36BD-Net File Transfer
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