Chapter 25, Use of tdr, 1 introduction – Nortel Networks DCT1900 User Manual
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Technical Product Manual - DCT1900
Installation Instructions, Use of TDR
Install-DCT1900/R8/mw
25-1
© 2000-2005
C
HAPTER
25
Use of TDR
25.1
Introduction
When programming Remote Base Stations using the CSMW Software, it is necessary to
determine the time delay of the Base Station cable. This is done using a TDR (Time Domain
Reflectometer). See the following paragraph for instruction on how to measure the delay of the
Base Station cable.
25.2
Determining the Delay of Remote Base Station Cable
The following instructions explain how delay is measured using the Tektronix model 1503B or
1503C TDR.
Refer to Figure 25-1 for an illustration of the front panel controls. In this illustration, each control is
numbered and the numbers are used to identify each control in the procedure that follows.
Fig.25-1 TDR Controls
1.
Turn power on (7). When you see a horizontal trace and division marks on the screen, the
TDR is ready to use.
2.
Set Impedance (2) to 93 ohms.
3.
Set Noise Filter (3) to 1 AVG.
4.
Set Vertical Scale (4) to 0.00dB
5.
Set DIST/DIV (5) to 100 ft.
6.
Set V
p
(6) to .99.
7.
Set Pulse Width (8) to 100 nS.
8.
Center the trace using the vertical POSITION control (9).
9.
Connect the test cable (terminated with two alligator clips) to the input jack (1).