Example 11: Taking Tdr Measurements - Tektronix 11801C User Manual

11801C User Manual
Taking TDR Measurements
This example demonstrates the TDR (Time Domain Reflectometry) feature of
the SD 24 sampling heads when they are used in combination with the
11801C. TDR is a method of examining and measuring a network or trans
mission line by sending a step into the network and monitoring the reflec
tions.
For this example you will need a 11801C with at least one SD 24 sampling
head installed. You will also need one SMA cable, preferably of 5 ns length,
and a static protection wrist strap.
Step 1: Initialize the 11801C (press the UTILITY button in the MENUS
column, touch Initialize in the major menu, and touch Initialize in the
verification pop up menu).
Step 2: Put on the wrist strap and ensure that it is connected to the
antistatic connector on the front panel of the 11801C.
Step 3: Attach one end of the cable to any SD 24 sampling head input.
Leave the other end unattached.
Figure 2 53: Connections for Example 11
Step 4: Press the WAVEFORM button, and touch the Sampling Head
Fnc's selector. See Figure 2 54.
Step 5: Touch Mainframe, 1 (or whichever channel you are using) and
then TDR Preset to define a trace and turn on TDR.
The sampling head will turn on a red light next to the channel input connec
tor, indicating that TDR is activated for that channel. TDR can be used on
each channel independently.
Example 11:
Not
Connected
2 91