Im having some trouble using Pico 6 and an external trigger. Using a reference signal in channel B I can trigger a Sample signal in channel A very well using the "auto" triggering options.
but when I use the same signal in external trigger it wont trigger properly.
the scope I am using is the 5203 and the signals are 20 MHz pulses. I had noticed an earlier post with a user having similar difficulties using a different scope. sounded like it was a driver/software issue.
Thanks for the reply (I thought Id be notified at a reply but something went wrong)
What I mean by "not triggered" is that the waveform is not stable in time as drawn on the screen. When I use B as a trigger reference for A, I can see the phase/time relationship between these signals is preserved. In other words, trace A and trace B are drawn the same way on the screen with each sweep.
But when I switch the triggering to external (using the exact same signal B as above), the A trace now bounces all over the screen (in time) - the waveform is drawn differently with each sweep.
I haven't tried the single trigger yet - will give that a go.
Rather than using auto, as this supplies the data every second even when the signal doesn't trigger and therefore will jump about, I would try using repeat trigger. I have just tried this on a a 5203, using Picoscope R6.6.16, and received a stable signal when the trigger input signal was moved between Channel B and EXT.
I tried this and it did not work for me. I can use the Rapid trigger on either A or B and the triggering is OK. But when I switch A to the EXT and try to trigger off that it does not draw a trace. Im using software 6.6.16.12.
I tried the rapid trigger and the same problem exists. the software is up to date (according to the updater).
Has anyone else had this problem before?
Perhaps the structure if the trigger signal is an issue: Im using a 20 MHz pulse as the trigger (not a square wave or sawtooth etc). When I use this signal in channel B with the other trigger modes it seems to work fine -it is just the EXT that seems to struggle.
Can you repeat the process, but with a slower trigger signal, say something in the 100kHZ to 1MHz range and see if you can trigger on the normal channels and the EXT channel. If it does then we need to look at the characteristics of your signal which may be at the limits of the EXT input circuitry.
The pulses in the waveform you posted are narrow and it is possible that they are not being seen by the EXT input trigger on all occasions and so causing the jumping around. If you try a 20MHz square wave do you get a more stable trigger albeit with a little bit of jitter ?