Configuration of the FDR settings is accomplished by selecting the Settings softkey. The settings softkey allows you to access the FDR settings screen or select the default settings.

The FDR Settings screen provides the following four settings for setting up the LST1700 to measure the cable system.
- resolution of the measurement
- velocity of propagation
- cable compensation (on/off)
- cable attenuation

Resolution of Measurement

The resolution of measurement determines the number of data points, maximum distance of, and distance resolution/accuracy of the measurement. This box contains LOW (64pts), MEDIUM (128pts), HIGH (256pts), and ULTRA (512pts). This setting greatly affects the time per measurement cycle, with LOW being quick (least accurate) and ULTRA being slow (most accurate). NOTE: The default setting for the Resolution of Measurement is LOW.

VOP

The velocity of propagation (VOP) is a property of the cable in use and greatly affects the measurement accuracy. NOTE: VOP values available are 0.3 through 1.0. The default the VOP value is .820.

NOTE:
Changing either the VOP or the cable attenuation manually will automatically set the cable type field to Manual Settings.

Cable Compensation

The Cable compensation box contains ON and OFF.  NOTE: The default setting for the cable compensation is ON.

Cable Attenuation

The cable attenuation @ 50MHz entry is only used if this field is set to ON. The cable attenuation direct entry field is used to calibrate the distance measurement for distant breaks. NOTE: Cable attenuation values available are 0.01 through 3.5. The default cable attenuation value is 2.1.