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Dennis,

I've not gone through that particular Tek XYZ book. I guess I should. Thanks for that as well.

?

Dave,

The key word is "USEFUL". The simple answer is that depends on what you mean
by useful which, in turn, depends on what you intend to measure with your
probe and scope.

To find the overall risetime of your entire system (probe and scope) add the
square of the probe risetime to the square of the scope risetime and take
the square root of the sum. For example: A scope with a 0.5nSec risetime
(700MHz bandwidth) combined with a probe with a 0.7nSec risetime (500MHz
bandwidth) will have a combined risetime that is 406MHz.

Thanks for reminding me of that. Duh. It seems I've misplaced some of my analog knowledge.

The square root of (0.5 * 0.5) + (0.7 * 0.7) = sqrt (0.25 + 0.49) = 0.86nSec
= 406MHz.

You can learn a lot by reading the excellent Application Note Tek wrote
called "The XYZs of Probes". It is widely available on the web.

I've not gone through that particular Tek XYZ book. I guess I should. Thanks for that as well. So much for reading a good physics book tonight. :)

Cheers,
Dave

Dennis

-----Original Message-----
From: davidnickdaniel, Sent: Tuesday, February 12, 2013 4:10 PM



Now, I understand about passive probe compensation and all that. What I
don't understand is what the 'scope-dependent bandwidth spec means. will
this type of probe be USEFUL close to 500 MHz when used with the >= 600 MHz
BW 700 vertical amplifiers (e.g., response close to 500 MHz), or is there
some probe/'scope dependency of which I am not familiar? I have several
P6106s which I am currently using.

Thanks.

Cheers,
Dave