Instructions

18 T3VNA User Manual
2.1 Basic Settings
2.1.1 Frequency
Set the frequency-related parameters and functions of the analyzer. The sweep will restart every time
the frequency parameters are modified.
The frequency range of a channel can be expressed by three parameters: Start Frequency, Center
Frequency and Stop Frequency. If any of the parameters change, the others will be adjusted
automatically in order to ensure the coupling relationship among them:
s t a r tstopspan
s t o p
) /2
s t a r tcenter
fff
f( ff


, Where
span
f
is the span.
2.1.1.1 Center Frequency
Set the center frequency of the current sweep. The center frequency and span values are displayed at
the bottom of the grid respectively.
 Modifying the center frequency will modify both the start frequency and stop frequency when the
span is constant (except when the start frequency or stop frequency reaches the boundary).
 In Zero Span, the start frequency, stop frequency and center frequency are always the same
value.
Table 2-1 Center Frequency
Parameter
Parameter
Default Full Span/2
Range Zero Span, 0 Hz - Full Span
Nonzero Span, 50 Hz - (Full Span -50Hz)
Unit GHz, MHz, kHz, Hz
Knob Step Span > 0, step = Span/200, min 1 Hz
Span = 0, step = RBW/100, min 1 Hz
Direction Key Step Freq Step
Related to Start Freq, Stop Freq
2.1.1.2 Start Frequency
Set the start frequency of the current sweep. The start and stop frequencies are displayed at the bottom
of the grid respectively.
 The span and center frequency vary with the start frequency when the Span does not reach the
minimum. For more details, please refer to “Span”.
 In Zero Span, the start frequency, stop frequency and center frequency are always the same
value.