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[email protected] etpm@whidbey.com is offline
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Default Bad probe-what's wrong?

On Thu, 24 Jan 2019 14:53:30 -0800 (PST), Terry Schwartz
wrote:

On Thursday, January 24, 2019 at 1:23:49 PM UTC-6, wrote:
I got my new to me BK precision 4001A function generator and I
thought I would see what it does. Tried looking at square waves but
they weren't square. The probe is a Probe Master 100 MHz. So, trying 3
other probes the display shows nice square waves. Using the output on
the TEK 465B 'scope itself also shows nice square waves.
The display should show horizontal lines 1 division long and
separated by 1.5 divisions, according to the dial settings on the
'scope. But instead the lines sweep up and down from the center and
the closest points of the lines are only about 1/5 of a division
apart.
I tried adjusting the probe by turning the adjusting screw with an
insulated screwdriver, and although it does flatten the shape some it
does not fix it.
So the probe must be trash but what could cause this behavior?
Thanks,
Eric


Sounds like it's AC coupled.

It is. DC didn't seem to change things but I don't know. Tomorrow I
will have time to set everything properly and will report back.
Thanks,
Eric