Hello
In the manual (!), HP reasons the 10M standard input resistance:
"Normally, the multimeter’s input resistance is fixed at 10 MΩ for all dc
voltage ranges to minimize noise pickup."
I explained that to myself like this: AC stray fields or noisy high impedance
sources induce noise input
Hi,
On 11/04/2014 10:53, frank.stellm...@freenet.de wrote:
Hello
In the manual (!), HP reasons the 10M standard input resistance:
"Normally, the multimeter’s input resistance is fixed at 10 MΩ for all dc voltage ranges to minimize noise pickup."
Oops! I'm ashamed to say I missed that!
In message <53482d9e.9060...@toneh.demon.co.uk>, Tony writes:
> I did find this explanation in the 3458A manual:
>
> When making DC voltage measurements, you can fix the multimeter's input
> resistance using the FlXEDZ command. This is useful to prevent a change
> in input resistance caused by
"You can't have your cake and eat it!"
well said
Too true, that the 10 MΩ reduces the noise pickup, but **only** when the DVM
input is **open circuited**, which is not so good for measuring anything if
the signal is not connected.
Otherwise the noise pickup is a function of the impedance of
Hi Paul,
On 11/04/2014 19:18, Poul-Henning Kamp wrote:
In message <53482d9e.9060...@toneh.demon.co.uk>, Tony writes:
I did find this explanation in the 3458A manual:
When making DC voltage measurements, you can fix the multimeter's input
resistance using the FlXEDZ command. This is useful to
In message <534840da.4070...@toneh.demon.co.uk>, Tony writes:
>> Many of the attributes of the input circuit are not there for
>> voltage metrology.
>>
>I can't think of any - I'd be interested to know what you have in mind?
One of the articles in HP Journal is specifically about how the
input ci
On 11/04/2014 20:59, Poul-Henning Kamp wrote:
In message <534840da.4070...@toneh.demon.co.uk>, Tony writes:
Many of the attributes of the input circuit are not there for
voltage metrology.
I can't think of any - I'd be interested to know what you have in mind?
One of the articles in HP Journ