Electrical Delay - Agilent Technologies 8753ET User Manual

Operating Concepts

Electrical Delay

Electrical Delay
The
ELECTRICAL DELAY
test device. This softkey must be used in conjunction with
WAVEGUIDE DELAY
transmission line the delay is being added to. These softkeys can be accessed by pressing
the key.
Scale Ref
Electrical delay simulates a variable length lossless transmission line, which can be added
to or removed from a receiver input to compensate for interconnecting cables, etc. This
function is similar to the mechanical or analog "line stretchers" of other network
analyzers. Delay is annotated in units of time with secondary labeling in distance for the
current velocity factor.
With this feature, and with
on page 1-38), an equivalent length of air-filled, lossless transmission line is added or
subtracted according to the following formula:
( )
=
Length meters
Once the linear portion of the test device's phase has been removed, the equivalent length
of the lossless, transmission line can be read out in the active marker area. If the average
relative permittivity (ε
calculation can be adjusted to indicate the actual length of the test device more closely.
This can be done by entering the relative velocity factor for the test device using the
calibrate more menu. The relative velocity factor for a given dielectric can be calculated by:
=
Velocity Factor
assuming a relative permeability of 1.
7-34
softkey adjusts the electrical delay to balance the phase of the
(with cut-off frequency) in order to identify which type of
→
MARKER DELAY
Φ
-------------------------------------------------------------------
(
( ) 1.20083 ×
Freq MHz
) of the test device is known over the frequency span, the length
r
1
--------
ε
r
COAXIAL DELAY
(refer to "Setting the Electrical Delay"
)
or