[volt-nuts] Short term "standard" cell?

[Frank Stellmach]

Hi Chris,

I remember getting an 1.5V mercury cell with a 4 1/2 digit DVM kit, so 
that's about the level of stability you can achieve with such a battery.

Alcaline batteries, and so on, forget about it.

For a Fluke 332A, you need on the order of 5ppm uncertainty for a proper 
adjustment of the 10V range, so all other "references" are just 
gimmicks. Drift and T.C. are way too high.

The only reasonable reference from Joe Geller (about 5ppm uncertainty, 
T.C. trimmed to near zero) is long gone, that's pityful.

Anyhow, a 10V reference alone is also not sufficient for calibration. In 
general, you'll need linearity adjustment (requires a Kelvin Varley 
divider like the 720A, or a 3458A ), and 100V and 1kV range adjustment 
require a Reference Divider like the 752A, or again a 3458A.

Therefore,  instead of poking around with these mediocre 10V 
"references", I'd look for a possibility to get access to a 3458A, maybe 
there's a friendly volt-nuts nearby.

Frank