Black Box ME475A-R2, Manual

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Configuration Overview
Switch S2-6: V.54 Loopback Test Enable
To reset the V.54 circuit, set switch S2-6 to the “ON” position, then back to the “OFF”
position.
Switch S2-7: 2-Wire/4-Wire Mode Selection
The setting for switch S2-7 determines whether the ME475A-R2 is operating in 2-wire
or 4-wire mode.
2.4 CONFIGURATION SWITCH SET “S3”
The DIP switches on S3 set the anti-stream control, local loopback enable, remote
loopback enable and receive (input) impedance levels for the ME475A-R2. Factory
default positions of Switch S3 are shown in the table below:
Switches S3-1 & S3-2: Input Impedance
The setting for Switches S3-1 and S3-2 determines the ME475A-R2’s input imped-
ance. This allows you to choose the optimum impedance setting for your application.
In long distance applications the impedance of the cable must match the impedance of
S2-6 Setting
Off V.54 Normal Operation
On V.54 Testing Disabled
S2-7 Setting
Off 4-wire (full or half duplex)
On 2-wire (half duplex only)
Table 4:
S3 Summary
Position Function Factory Default
S3-1
Input Impedance
On
200 ohms
S3-2 Off
S3-3 Not yet assigned N/A
S3-4 Mode Selection On Point to Point
S3-5 Local Loopback Off Disabled
S3-6 Remote Loopback Off Disabled
S3-7
Anti-stream Control Off Disabled
S3-8