Micsig Diff Probe Inverting Measurements When Switching Attenuation

[bostonman]

I either followed your advice and/or already did that using a 9v battery.

Think I figured out the scope. Whenever I connected the (per the label) 10:1 Agilent probe (part number: 10074C) to the scope, it automatically detects it and removes a scope probe menu item which happens to be the attenuation.

The menu that remains is external scaling. When I changed this setting, thinking I was changing the attenuation, I was changing the gain. At some point the attenuation must have automatically been on x10, I set the gain to x10, saw it was wrong (ten times higher), changed the gain to x1, didn't understand why the scope was on x1 and the probe being x10, so I tried 0.1.

In any case, the front scope test point is 0-1V. I don't know why this is 0-1V as most scopes I've seen are usually 0-5v.

Now that I understand the scope probe menu stuff, maybe I won't mess up this portion of my measurements; and I now realize I saturated the diff probe which hopefully won't happen again.