Oscilloscope question

[David Holland]

On Fri, 2005-04-08 at 11:55 -0400, John Allain wrote:

<snip>

I don't claim to be a EE, but FWIW...

(I'm sure someone will put me in my place if I say anything out of
line. :-)   )

> Subquestion Number one for me would be the reasoning why 
> those probes are so important.  How bad are readings taken 
> with just direct wired connections?

Impedance.  What effect does the "load" of the scope have on the circuit
being tested?   The "load" of the scope is (probably) significantly more
w/ out the probes.

> 
> Should a scope rating 2X the computer clock speed keep the
> readings useful?

I believe that's correct.  My (old) B&K was targeted for TV repairmain,
so its rating is a mere 10Mhz.   (Analog TV is spec'd at a 4Mhz
bandwidth)

David