HP 3562A Operating Manual page 364

FLAT TOP-selects the flat top window for both input channels. The flat top window
offers greater amplitude accuracy but lower frequency resolution than the
Hanning. It is generally used when a component's amplitude must be
measured accurately, such as when usinq a fixed sine stimulus.
FORCE CHAN 1-selects the force window for Channel 1 , This window passes the
input signal for the specified amount of time then attenuates it to the aver­
age value of the remaining data for the remainder of the time record. Enter
the time width using the E ntry group. To find the current record length,
press
STATE TRACE
dow is generally used in impact testing to cancel unwanted signals occur­
ring before and after the actual impact.
FORCE CHAN 2-selects the force window for Channel 2. This window passes the
input signal for the specified amount of time then attenuates it to the aver­
age value of the remaining data for the remainder of the time record. Enter
the time width using the Entry group, To find the current record length,
press
STATE TRACE
dow is generally used in impact testing to cancel unwanted signals occur­
ring before and after the actual impact.
FORCE/EXPON-displays the menu for selecting force and exponential windows.
Because the force and exponential windows are single-channel, they can
be mixed in two-channel measurements. If you select the frequency
response measurement with the force window on one channel and expo­
nential on the other, the channel for which you select the force window gets
both the force and exponential windows. Chapter 1 offers more details.
HANN -selects the Hanning window for both input channels. The Hanning offers
higher frequency resolution but lower amplitude accuracy than the flat top
window, It is the most commonly used window and is usually applied in
random noise measurements.
RETURN--redisplays the
WINDOW
UNIFRM (NON E)-selects the uniform window for both channels. This window's rec­
tangular shape does not attenuate any portion of the time record. The uni­
form window is generally used with self-windowing functions such as burst
and random chirps.
USER SAVD 1- selects the time waveform stored in the SAVED 1 location (see
as the window to be applied to both channels. This must be a
RECAll)
time domain waveform to be used as a window. Chapter 1 explains how to
create and store user windows.
and look under FREO: REC LGTH. The force win­
and look under FREO: REC LGTH. The force win­
menu.
Chapter 12-Operating Reference
WINDOW (cont)
SAVE
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