Selectable
Windows
Four windows are selectable: Hanning, for best frequency resolution and
general purpose use; flattop, for best amplitude accuracy; rectangular, for
single-shot signals such as transients and signals where there are an
integral number of cycles in the time record, and exponential for best
transient analysis.
Window
Characteristics
Window
Highest
Side Lobe
(dB)
3dB
Bandwidth(b
ins)
6dB
Bandwidth(b
ins)
Scallop
Loss
(dB)
Rectangular
– 13
0.89
1.21
3.92
Hanning
−
32
1.44
2.00
1.42
Flattop
– 70
3.38
4.17
0.005
FFT Freq Range
dc to 100 MHz (54600/54601/54645)
dc to 150 MHz (54602)
dc to 60 MHz (54603)
dc to 500 MHz (54610/54615/54616)
Freq Span Control
This control allows you to specify the frequency span of the FFT display.
When the Span is adjusted the display will expand or contract about the
center frequency as set by the Center Frequency control. Refer to Figure
3-1 for the limits of the Frequency Span control.
Center Freq
Control
This control allows you to specify the frequency at the center of the FFT
display. When the Frequency Span is changed, the FFT display will
expand or contract about the frequency at the center of the display.
Refer to Figure 3-1 for the limits of this control.
Move 0 Hz to Left
Pressing this soft key will move the FFT display so that the left hand edge
of the display will be 0Hz.
FFT Vector
display
When the time domain display is turned off the FFT display will be
displayed in vector drawing mode. The time domain display can be
turned off by pressing the Channel # key twice
Display
FFT vertical units in dB.
Units/Div
This control allows you to adjust the vertical scaling of the FFT display in
a 1-2-5 sequence from 1 dB/div to 50 dB/div.
Reference Level
This control allows adjustment of the reference level of the FFT display
across a range of 400 dBV. The minimum setting is -196 dB at 1 dBV/div
decreasing to 0 dBV at 50 dBV/div. The maximum setting is 400 dBV at 50
dB/div, decreasing to 204 dB at 1 dBV/div.
Programmability
All front-panel controls are fully programmable over GPIB (54657A)
or RS-232 (54658A and 54659B)
Reference Information
Operating Characteristics
3–4
Summary of Contents for 54657A
Page 5: ...Installation 1 Reference Information 3 Operating the Measurement Storage Module 2 Index v ...
Page 6: ...vi ...
Page 8: ...3 Reference Information Operating Characteristics 3 3 Index Contents Contents 2 ...
Page 9: ...1 Installation ...
Page 16: ...1 8 ...
Page 17: ...2 Operating the Measurement Storage Module ...
Page 73: ...3 Reference Information ...
Page 80: ...3 8 ...
Page 87: ...Voltage Time Cursors Press this key to obtain this menu ...
Page 88: ...Print Utility Trace Trace Press this key to obtain this menu ...