O-Scope Methodology

Interesting new forum layout. It'll take some getting used to. 


Alright, I am writing a procedure for a Tektronix MSO2024B and have run into an intriguing conundrum with the Vertical Position test. For those familiar with Tek Scope cal's this is the test were vertical position is set to the top or bottom of the screen, the offset is set to max and then a DC voltage is applied to get the sweep to fall back on the zero line. If I understand this test correctly, it is to ensure that the vertical position visually displays correctly and is a separate function from DC Gain as the gain is a test of the measurement circuit but not the accuracy of the deflection of the sweep on the screen. 

I've seen other cal labs do this by having Met/Cal run the setup then running the OPBR FSC to have the operator verify that the sweep is visually within a couple sub-divisions of the zero line. 

I know this is problematic for the computer to test as it is a visual confirmation but I was wondering if anyone had any creative solutions to this to actually fully automate this step. I've been exploring the possibility of an auto-set cursor but haven't been satisfied with the results as yet. Another thought that occurs to me is if this check is even relevant on a fully digital scope or if this is a carry over from the days of analog scopes that no one ever thought to re-examine the need for.

Does anyone have experience with this?

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