HP 8530A, Руководство по эксплуатации и программированию, Страница: 216 / 439

Response Functions
Figure 9-5. Results of Smoothing
Delay F eatures
Electrical Delay
The electrical delay function acts as an electronic line stretcher , providing a calibrated phase
compensation versus frequency with femtosecond resolution. In eect, the specied delay
is added to the reference signal path in order to make measurements such as deviation
from linear phase , described later in the Viewing Data Chapter . Electrical Delay can be set
independently for each parameter on each channel and aects both the phase and delay
frequency domain trace and the time domain trace .
Using Electrical Delay
Press RESPONSE 4
MENU
5
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DELAY MENU
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ELECTRICAL DELAY . The A ctive function shows
electrical delay in terms of seconds , as well as the equivalent length (in meters), relative to the
current V elocity F actor setting. After F actory Preset, V elocity F actor is relative to the speed of
light in free space .
F or example , select 4 PHASE 5 , and then use the knob to change the value . Notice that when
delay is added, the D annotation appears on the left side of the display . Y ou can use the step
keys and the numeric and units keys to enter the amount of electrical delay desired.
Delay Options
The two options for the electrical delay feature are:
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COAXIAL DELAY
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WAVEGUIDE DELAY
Coaxial and W aveguide softkeys allow you to select the media type simulated by the electrical
delay function.
Coaxial Delay . F actory Preset selects
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COAXIAL DELAY which applies a linear phase
compensation to the trace . That is , the eect is the same as if a corresponding length of perfect
vacuum dielectric coaxial transmission line was added to the reference signal path.
Response Functions 9-7