Fluke CombiScope PM3370B User Manual page 134

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AVERAGE
Description:
Valid in digital mode only.
Averaging is a process to reduce random noise without losing bandwidth.
Averaging can only be used for repetitive signals.
Every sample point is calculated after every subsequent acquisition as follows:
new = previous
In this formula "previous" is the result of the average function after the previous
acquisition, on the same sample position as the measured one. "C" is the
average-factor. Noise is reduced by a factor which is equal to the square root of "C".
Average values for "C" can be selected from 2 to 4096 in a binary sequence. To
do so, use the TRACK control in the ACQUIRE menu.
Averaging also results in a higher vertical resolution resulting in higher
measurement accuracy.
Averaging can be quickly switched on and off with the direct access key
(AVERAGE) on the front panel, or via the ACQUIRE menu. Once activated,
average is a continuous process until it is switched off. However, whenever the
display is changed (e.g. POS, AMPL/DIV) the average process will restart.
AVERAGE is mutually exclusive with ENVELOPE. If the ENVELOPE mode is
selected, AVERAGE is automatically switched off.
Key sequence:
AVERAGE
TRACK
ACQUIRE
measured previous
+ ----------------------------------------------------------- -
Key to switch the AVERAGE function on or off.
Control to select the AVERAGE factor.
ST6555
9303
FUNCTION REFERENCE
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C