PicoScope 7 Software
Available on Windows, Mac and Linux
No way to align filtered signal segments
No way to align filtered signal segments
Hello, I measured a signal on 2207B.
It was very noisy, so I activated 10 kHz filtering. It turned into a clear signal, very nice feature!
However, after that the trigger became useless since the trigger captures the signal before the filtering. See the picture. The trigger point is not on the edge.
Is it possible to stop the signal (digitally) after the filtering? If not, can you add this as a new feature?
It would be really nice to have a "digital trigger" or a "signal alignment" function because after the signal is filtered, the trigger becomes useless, the signal is jittering on the screen (jumping from left to right around the trigger point) and there's no way to align the signal edge on a specified position to fix the jittering. The original signal is not visible, just the filtered signal and so it's odd the trigger point does not belong to the visible signal.
However, after that the trigger became useless since the trigger captures the signal before the filtering. See the picture. The trigger point is not on the edge.
It would be really nice to have a "digital trigger" or a "signal alignment" function because after the signal is filtered, the trigger becomes useless, the signal is jittering on the screen (jumping from left to right around the trigger point) and there's no way to align the signal edge on a specified position to fix the jittering. The original signal is not visible, just the filtered signal and so it's odd the trigger point does not belong to the visible signal.
Re: No way to align filtered signal segments
The filtering occurs after data capture, so the only way to stabilize the signal would be to adjust the trigger level, currently you have this set in the busiest part of the signal range. I would be looking to put the trigger around 80mV in this capture.
There will still be a little bit of jitter, although changing to an advanced trigger and using pulse width options would probably help, and the trigger diamond would not sit on the trace once you have applied filtering, but it may help with your tests.
There will still be a little bit of jitter, although changing to an advanced trigger and using pulse width options would probably help, and the trigger diamond would not sit on the trace once you have applied filtering, but it may help with your tests.
Martyn
Technical Support Manager
Technical Support Manager
Re: No way to align filtered signal segments
The 80 mV would help on signals with the peaks but not without them. I haven't tried an advanced trigger yet, but I will check this out for sure.
Do you think that the digital trigger/alignment point is a bad idea? The aim is to align the edge in the visible signal on the screen, not in the invisible one, to stop the flickering. Doing it digitally, it would be super stable (no skipping, exact pixel match). Maybe I'm wrong, not aware of how you implemented the triggering, but for me it seems to be good idea at least for now.
Do you think that the digital trigger/alignment point is a bad idea? The aim is to align the edge in the visible signal on the screen, not in the invisible one, to stop the flickering. Doing it digitally, it would be super stable (no skipping, exact pixel match). Maybe I'm wrong, not aware of how you implemented the triggering, but for me it seems to be good idea at least for now.
Re: No way to align filtered signal segments
As the filtering is done post capture, this is not possible. If you were to take the approach of aligning data so that the filtered signal passes through the trigger point, you would have no trace data either at the start of the end depending upon which way you moved the trace, which would have an effect on other math channel functions if used. So looking at advanced triggers would recommended, but even then there is no guarantee of being able to produce a stable repeating trigger with so much signal noise.
Some of our scopes do have a hardware bandwidth limiter that can assist, although this is not available with 2000 series devices. You could use external filters to precondition the signal before it reaches the scope, however it is often the noise that is of interest and causing the issues under investigation which is why people capture the dirty data, and clean it post collection.
Some of our scopes do have a hardware bandwidth limiter that can assist, although this is not available with 2000 series devices. You could use external filters to precondition the signal before it reaches the scope, however it is often the noise that is of interest and causing the issues under investigation which is why people capture the dirty data, and clean it post collection.
Martyn
Technical Support Manager
Technical Support Manager