No matter how many channels you open, the bandwidth of each channel is 250MHz.
But when you open four channels, the sampling rate of each channel is reduced from 1GSa/s to 250MSa/s.
Collect 3 to 5 points in each period, it may draw a correct waveform.
If you use 250MSa/s sampling rate to collect 250MHz waveform, only one point is collected for each cycle. The waveform will be seriously distorted.
Post time 2018-1-29 10:00:32