EEVblog Electronics Community Forum
Products => Test Equipment => Topic started by: alager on January 18, 2019, 05:54:05 pm
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Following various blogs about segmented memory, like this one: https://community.keysight.com/community/keysight-blogs/oscilloscopes/blog/2017/02/01/how-segmented-memory-can-help-find-dinosaurs (https://community.keysight.com/community/keysight-blogs/oscilloscopes/blog/2017/02/01/how-segmented-memory-can-help-find-dinosaurs) I tried it on my scope, with not so good results. Am I misunderstanding something?
Attached is
- the RF burst test waveform at 20us/div (looks good)
- 20ms/div, then using the zoom feature (looks good)
- then simply turn on segmented memory and the signal goes to crap.
My understanding is that the segmented memory mode should simply ignore the dead time between samples.
Please enlighten me, as this does not seem to match the marketing pitch for this feature. Do I need to change the trigger somehow?
Thanks
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Just looks like your sample rate took a massive hit. Typically you turn the timebase down to see what you want, then use segmented mode to get many different captures. You don't, especially on a scope with so little memory, want to pull the timebase out and run in segmented mode. So you'd want to do 20us and then segmented for potentially best results. Then you should get multiple high detail captures as opposed to your low detail long timebase + zoom. That'll get you the most bang for buck out of the memory you have.
Final edit: 20ms and zoom does not look good.
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Okay, I just did as you suggested, and that seems to work and make sense. I guess my main confusion was form all the Keysight videos and blogs, they didn't demo it the way you just explained it.
Thanks!
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Yea, I haven't seen their videos on that but I could tell where the confusion was. Segmented memory is really nice because it saves you from wasting memory on the dead time between triggers.