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Products => Test Equipment => Topic started by: mayor on May 31, 2014, 01:43:22 am

Title: DS1074Z zoom bug?
Post by: mayor on May 31, 2014, 01:43:22 am
I have a square waveform, which appears fine until I zoom in below 200mV. Has anyone else seen this? The attached shows 500mV/div, but the odd one is after zooming in to 200mV and stopping capture, then going back to 500, for comparison to the running 500.

Anyone?
Title: Re: DS1074Z zoom bug?
Post by: Hydrawerk on May 31, 2014, 02:04:12 am
I am not sure but isn't this caused by oscilloscope overdrive? This is a common problem or feature of most scopes. http://cp.literature.agilent.com/litweb/pdf/5989-0068EN.pdf (http://cp.literature.agilent.com/litweb/pdf/5989-0068EN.pdf)
Title: Re: DS1074Z zoom bug?
Post by: mayor on May 31, 2014, 09:01:31 am
I am not sure but isn't this caused by oscilloscope overdrive? This is a common problem or feature of most scopes. http://cp.literature.agilent.com/litweb/pdf/5989-0068EN.pdf (http://cp.literature.agilent.com/litweb/pdf/5989-0068EN.pdf)

 :palm: ...thanks.
Title: Re: DS1074Z zoom bug?
Post by: jimjam on June 02, 2014, 05:19:44 pm
How are you liking the DS1074Z so far?
Title: Re: DS1074Z zoom bug?
Post by: max666 on June 02, 2014, 06:44:12 pm
I tried to reproduce your waveform on my DS1074Z, but wasn't able to get that result. I'm happy to try again, if you can provide more detail on what exactly you do, to get that waveform.

But I'm inclined to agree with Hydrawerk, I too think this feature might be caused by overdrive.
EDIT: Although you're looking at a 1.15kHz signal, so recovery time should be way quicker than what we see. Maybe it is a zoom bug.  :-//
Title: Re: DS1074Z zoom bug?
Post by: tom66 on June 02, 2014, 09:27:34 pm
This isn't a bug, and it happens with many oscilloscopes. By setting the gain that high, you are overdriving the input amplifier so it behaves poorly. It's not harmful but can cause confusing results. There was a thread about this on the 2000X Agilents too, iirc.
Title: Re: DS1074Z zoom bug?
Post by: alexwhittemore on June 03, 2014, 06:36:16 am
I tried to reproduce this too but had no luck. If anyone comes across a set of conditions that seems repeatable, I'd love to hear about it.