User Manual

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Generally speaking, improve sensitivity if test value 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 frequency 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.
5.19 Output Port
There are four output ports on the front-rear panel: CHA, CHB, Sync and 10MHz output.
Forbid to input signal from output port, or the waveform generator will be damage.