
2-17
Application Tutorials
Tutorial 5: Use Software Filters
Eyeline Display Showing Laser Overshoot 
Load the Software Filter 
2Place the  70874A memory card in the front-panel card slot. 
3Display the catalog of files on the memory card by pressing: 
Mass Storage 
4Turn the front-panel knob to highlight the file "a_bt248832". 
5Load the file into user-corrections by pressing : 
LOAD FILE 
This file simulates a 4th-order Bessel-Thomson filter with a cutoff at th ree-
quarters of the bit rate. This allows you to observe the laser tran smitter signal 
in a specified bandwidth. This software filter is equivalent to using a hardware 
filter, except that trace noise may be suppressed more. 
6Apply the filter data to the traces by pressing: 
Trg,Cal, more 1 of 2, usr cor ON OFF ON