EXFO FTB-800 Series for FTB-1 - Manual (Page 159)

Test Setup - Test Configurator, Timer, and System
NetBlazer 149
ISDN PRI - ISDN Settings

Threshold allows to enter the threshold value that will be used to
declare the pass/fail verdict.
For Count, enter the maximum bit error count allowed before
declaring a fail verdict: 0 (default) to 999999.
For Rate, enter the maximum bit error rate allowed before declaring a
fail verdict: 1.0E-14 to 1.9E-01 (default is 1.0E-12).

Idle Code allows the generation of idle code when a B-Channel is in
idle state or active with a Speech or 3.1 kHz call without the headset
connected. Choices are 00 to FF (default is 7F). Idle code is not present
on a channel connected to the headset.

Binary check box when selected allows to enter Idle Code in Binary
format else it is in Hex format.
Restore ISDN PRI Defaults
Reverts the current test application to its default factory settings.