Cable and Antenna Analyzer Measurement Guide : Cable and Antenna Analyzer : Cable and Antenna Measurement Setup : Limit Lines
 
Limit Lines
Pressing the Shift key and the Limit (6) key brings up the Limit menu. The cable and antenna analyzer supports both single limit and multi-segment limit lines. The multi-segment limit lines can have as many as 40 segments across the entire frequency or distance span. Limit lines can be used for visual reference, or for pass/fail criteria using the limit alarm. Limit alarm failures are reported whenever a signal is above the upper limit line or below the lower limit line. Limit lines are stored with setups and can be recalled at a later time.
Single Limit Line
1. Press Shift and then Limit (6) to enter the Limit menu.
2. Press the Limit On/Off key to turn on the Limit.
3. Press Single Limit and then use the numeric keypad, Up/Down arrow keys, or the rotary knob followed by Enter to change the limit value.
4. Press the Limit Alarm key to turn on or off the Limit Alarm.
Adjusting the Volume of Limit Alarm
1. Press Shift and then System (8)
2. Select the System Options submenu.
3. Press the Volume key.
4. Use the Up/Down arrow keys, rotary knob, or enter a value between 1 and 9 to adjust the volume.
Single Limit Lines
Segmented Limit Lines
The following procedure creates limit lines for a Return Loss Measurement. Limits are set to:
• 0 dB between 1800 MHz and 1830 MHz
• 13.5 dB between 1830 and 1870 MHz, and
• 0 dB between 1870 and 1900 MHz.
The frequency is set from 1800 MHz to 1900 MHz.
1. Press Shift and then Limit (6) to enter the Limit menu.
2. Press the Multi-Segment Edit key.
3. The default limit line has two points. In this example, 3 segments require 6 points. Press the Add Point key four times to add four more points.
4. Press Next Point Left until the highlighted red point is the first point to the left. Press Point Value and enter 0 dB.
5. Press Next Point Right and set the Point Value to 0 dB for the second point from the left. Press Point Freq and enter 1830 MHz.
6. Press Next Point Right and set the Point Value to 13.5 dB for the third point from the left. Press Point Freq and enter 1830 MHz.
7. Press Next Point Right and set the Point Value to 13.5 dB for the fourth point from the left. Press Point Freq and enter 1870 MHz.
8. Press Next Point Right and set the Point Value to 0 dB for the fifth point from the left. Press Point Freq and enter 1870 MHz.
9. Press Next Point Right and set the Point Value to 0 dB for the sixth point from the left. Press Point Freq and enter 1900 MHz.
Segmented Limit Lines