Metrix DOX 2 Series, User Manual

Page: 35 / 48

Kit Demo for METRIX Oscilloscopes 33
2. Using the digital filters
2.1 2 kHz square wave with a 62 kHz sine wave superposed on its plateaus
a) Display of the 2 kHz square wave with a 62 kHz sine wave superposed on its plateaus:
Remark: the frequencies of the Digital Filters depend on the sampling frequency and therefore on the time base
range (M = 250µs), so we recommend observing the details of the signals with the "Delayed" time base
(W = 25µs) and a normal memory depth; this does not alter the cut-off frequencies of the filters, which depend
on the main time base range, M = 250µs.
b) A
"low-pass" digital filter having a high cut-off frequency of 25 kHz is applied to this signal:
The 62 kHz sinusoidal signal, which is above the high cut-off frequency of the filter, disappears and the edges
of the 2 kHz square wave are rounded (see below).