HP 54520 Series Service Manual page 23

Waveform Save
Operating Characteristics
Maximum Displayed Frequency 5 Hz to 1 GHz selectable (real-time acquisition).
Display is from de to a selectable upper frequency, in steps from 5 Hz to 1GHz. Maximum
frequency displayed is 1/2 the sample rate.
Window Characteristics The window characteristics are shown below.
Highest Side 3qB 6dB Scallop
Lobe Bandwidth Bandwidth Loss
Window (dB) (bins) (bins) (dB)
Rectangular -13 0.89 1.21 3.92
Hanning -32 1.44 2.00 1.42
Flattop -10 3.38 417 0.005
Highest Side Lobe The minimum attenuation in the stop band. It indicates the level of leakage
present in the filter; that is, how high the skirts are in relation to the main peak,
3 dB bandwidth The width of the peak at a level 3 dB down. A narrow 3-dB bandwidth helps
in separating frequency peaks that are close together.
6 dB Bandwidth The width of the peak at a level 6 dB down.
Bins The distance between frequency points. One bin equals the resolution.
Scallop Loss The attenuation of the peak half way between bins. The scallop loss determines
the amplitude accuracy of a window. It measures the attenuation of a signal that falls between
frequency bins versus one that is exactly on a frequency bin.
Split display operation A time-domain waveform and its FFT spectrum can be
displayed simultaneously on the top and bottom halves of the screen. Four FFT spectra
can be displayed simultaneously in the same way. Four sets of time-domain waveforms
and their spectra may also be displayed simultaneously.
Log Display Sensitivity and offset can be set by the user.
The oscilloscope contains four nonvolatile waveform memories, two volatile pixel memories,
and 665 multiple failure memories. The four nonvolitile memories can store four waveforms
up to 32K each. The 665 multiple failure memories store 500-point records. Waveform
memories store single-valued waveforms, such as an averaged waveform. If an envelope
waveform is stored to a waveform memory, it is automatically stored with the upper waveform
in one waveform memory and the lower waveform in another. You can perform automatic
measurements on the four nonvolatile waveform memories but not the volatile pixel memories.
Waveform memory pairs ml/m2 and m3/m4 also store the upper and lower limit masks used
during compare testing. You can create and edit these masks using sample signals, or you can
create them manually.
Pixel memories store an entire screen of waveform data. Use them for storing multiple
overlapping waveforms and infinite persistence waveforms.
Multiple memories store failure data from limit and compare tests. You can view or transfer
this data to the waveform memory for nonvolatile storage or measurement.
Waveform and pixel memories can be saved to the disk drive (Disk menu).
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