[volt-nuts] Traveling Standards

[Brent Gordon]

Fred,

You may have some light-sensitive components.  Diodes with glass 
packaging are especially bad.  Try blocking the light with cardboard and 
see what happens.  Keep your hands away from your meters while moving 
the cardboard around.

Brent

On 10/20/2012 2:47 AM, Fred Schneider wrote:

> But i think I have a problem regarding magnetic fields or other sources because I have strange issues while meauring using the 332 and KV deviders or my LM399.
> I looked to it with a friend and he thinks it is some magnetic field or common mode thing.
> I had powered everything off, even the lights. Then both 7,5 digit meters showed the same values, turning the polarity did not matter. Both KVs were lineair upto 1 uV. Using my 399 or Fluke 332, also tested the 332 divider dircect.
> Then with the lights on severa instruments ect. A big difference if i change polarity, both meters gave different readings, both KV dividers gave excact the same non lineairity. I did this several days and up to about 1 mV !! between 100 mV and 10V but an verage of a few hundered mV) if I power all stuff down exept the 332 and 7106 all is perfect again. All intruments are grounded. I use shielded cables to the meters and from 332 to KVs from Beats me :-(
> So I think your standard performs well if it is this stable while tossing around, i wish my 332 and LM399 was that stable ( or more, the environment was more standard friendly becaus all powered  down things are much more stable)
>
> Fred PA4TIM