Aethra D2000 Lite, User Manual, Page: 87 / 186

USER’S MANUAL ISDN TESTER AND ANALYZER D2000
PRO
/D2000Lite/D2000
To measure the ECHO time:
1 Activate a connection to a terminal with data loop (if not
already existing).
2 If the Tone Generator test is active, press this key in order
to end the it.
3 To start the line response time measurement.
In the result pages it is displayed the minimum and maximum response time and the
level’s measurement of the eco signal (RMS).
The ISDN is oriented to transport one byte at a time (byte-timing).
For a correct measurement, the remote terminal must make a data loop on the
channel.
This measurement can be useful in case of users with video
terminals that are sensitive to the delay between B channels. A
channel can have a different delay values for different calls,
according to the call route in the switching exchanges.
The instrument can measure delay up to ten seconds. In case of higher values, or if
the remote terminal does not make the data loop, the instrument will inform the user
with the "NO REMOTE LOOP".
Once the delay has been measured, the delay value is saved until the call is
disconnected. Subsequently the active call can be looped with the LOOP softkey.
See § 3.4.2. The delay for this call is displayed on the B channel status page. See
chapter
7 .
CHAPTER 3 - PERFORMING A MANUAL TEST
87