Anritsu S251B - Manual (Page 64)

DTF Measurement (Determining the Length of the Cable)
Step 15. Disconnect the Load and connect the test port extension cable to the Site Master
test port.
Step 16. Connect the Short to the open end of the test port extension cable.
NOTE:
The number of data points displayed can be changed by selecting
RES in the
DTF AID table.
Setting the Amplitude Scale
Step 17. Press the AMPLITUDE or LIMIT key to call up the Scale Menu.
Optional: Press the AUTO SCALE key to optimize the amplitude scale.
Step 18. In SWR mode, press the TOP soft key and enter 3, 0 using the keypad or
Up/Down arrow key. Press ENTER to set the top scale. (In Return Loss mode,
enter 0.)
Step 19. In SWR mode, press the BOTTOM soft key and enter 1 using the keypad or
Up/Down arrow key. Press ENTER to set the bottom scale. (In Return Loss
mode, enter 54.)
Setting the Marker
Step 20. Press the MARKER key to call up the Markers menu.
Step 21. Press the M1 soft key to select the M1 marker function. (Note: pressing the
ON/OFF soft key activates or deactivates the M1 marker function.)
Step 22. Press the MARKER TO PEAK soft key to find the cable length.
Step 23. Press the BACK soft key or the ESCAPE key to return to the previous menu.
Figures 4-13 and 4-14 show cable length displays in SWR and Return Loss
modes.
NOTE:
Refer to page 4-4 for instructions on saving and recalling a setup or display.
4-18
Chapter 4 Measurements