I'm using the PicoScope 2204, with version 4.6.92, to take a measure of sine wave of 1.8 MHz.
When i select the AUTO trigger the waveform of the signal is not stable, but the frequency mesured is correct; if I select the ETS the wave becomes stable but the frequency, and the waveform show, becomes exactly half of the original, 900 KHz.
Two problems; one the measurement is wrong, but the main problem is that the waveform is jittering. I have managed to recreate your problem. This is a bug in the driver you should not have to put ETS on. I have reported it as a bug. Thanks for pointing it out.
Thanks for the analasys !
Others informations: the same problem occurs with a Picoscope 3224 (same software 6.4.92) and the signal applied comes from a reference generator, therefore it's jitter free.
Hi I cannot recreate the problem on the 3224 what I think you are seeing is the Sin(x)/x interpolation.
With linear interpolation this connects the dots between the sampled points and you normally need a significantly higher sample rate to get a very good looking signal. Using Sin(x)/x interpolation this algorithm (used by many scope manufacturers) means that you do not need to sample as high to get a good looking waveform.
By default Sinx(x)/x is on and the trigger looks as if it is jittering, If you switch of sin(x)/x interpolation you will see the that the waveform is triggering correctly.
You can switch this off by going into Tools-> Preferences and then selecting the sampling tab and switch it off
Hello,
i tried to disable the sin (x) function but the defect remains!
I learn that even if activated the second channel B, the 1 MHz signal 1 becomes stable (see. Two_channel_without_defect.psdata), but with only active the channel A the defect is always present (see One_channel_with_defect.psdata)