HP 8712ES User Manual page 463

Options
75 Ohms (Option 1EC)
Provides 75 ohm system impedance.
Fault location and structural return loss (Option 100)
For fully characterizing cable performance and antenna-feedline
systems, this option provides both fault location and structural return
loss capability. Fault-location measurements help identify where
cable or system faults, such as bends, shorts, or corroded or damaged
connectors, occur. In addition to displaying faults in terms of distance
into the cable or feedline, the magnitude of the fault is also displayed.
Structural return loss is a special case of return loss (reflection)
measurements, optimized for measuring periodic reflections of small
magnitude. These periodic reflections can occur from physical damage
to the cable caused by rough handling, or from minor imperfections
imparted during the manufacturing process. Structural return loss
problems occur when these periodic reflections sum at
half-wavelength intervals, causing high signal reflection (and low
transmission) at the corresponding frequency.
Step Attenuator (Option 1E1): HP 8712ET/8714ET only
This option adds a built-in 60 dB step attenuator, extending the
source output power low-end range to −60 dBm. This attenuator is a
standard feature on the HP 8712ES/8714ES.
Transport case and fault location and structural return
loss (Option 101)
Combines a rugged transport and operation case (HP part number
08712-60059) with Option 100 for field measurements of fault
location and structural return loss.
ES User's Guide
Specifications
9-53