PeakTech 4105 Bedienungsanleitung Seite 128

5.18.5 Sensitivity
Press 〖Sensitiv〗softkey then select 'Sensitive' to configure the desired sensitivity value.
The bigger the value is, the higher the sensitivity is. The influence for sensitivi ty adjustment
is small if the amplitude of tested signal is higher. But if the amplitude of measured signal is
lower and noise contained in signal, you need adjust the sensitivity to get a better result.
Generally speaking, improve sensitivity if test valu e of frequency is less than standard
frequency of measured signal, or lower sensitivity if test value of frequency is greater than
standard frequency of measured signal.
5.18.6 Coupling Mode
Press 〖Coupled AC/DC〗softkey to choose between AC or DC. If freq uency of measured
signal is higher with DC offset, select AC mode and set the trigger level to be 0. If frequency
of measured signal is lower than 1Hz or amplitude lower than 100mVpp, select DC mode
and adjust trigger level properly to get a better result.
5.18.7 Low-pass Filter
Press 〖Filter On/Off〗 softkey to turn on or off the low-pass filter. When frequency of
measured signal is lower with high-frequency noise, frequency testing value will be greater
than standard frequency value of test signal, low -pass filter should be turned on to filter the
high-frequency noise, then get an accurate result. But when frequency of measured signal
is higher with lower amplitude, the low-pass filter will attenuate the high-frequency signal
and frequency testing value will be less than standard frequency value of test signal even
can't get a result, low-pass filter should be turned off. The upper limit frequency of low -pass
filter will be around 50kHz.
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