[volt-nuts] Solartron 7081, other meters, and some voltage standards

[J. L. Trantham]

I have been testing my 'new' 7081 and suspect I have arrived at the 'usual'
cross roads of what to believe.

I have two Fluke 731B's that I got from 'the site'.  I replaced the battery
packs in months past and have left both on for the past 3 or 4 days along
with the 7081 and other meters, an HP 3478A and an HP 3457A, as well as a
Fluke 335A voltage standard set to 10.000000 volts, all from 'the site'.

Regarding the 731B's, one is a 'white' face and the other is a 'black' face
and both are set to 10V.

I left the 7081 connected to the 'black' face 731B, set to 7 X 9 (3.2s) in
'TRACK', and walked in to the shop to find it reading 10.000000.  When
connected to the 'white' face 731B, it reads 9.999898 and, when connected to
the 335A, it reads 10.000392.

The 3478A reads 10.0001, 10.0000, and 10.0005, respectively.  The 3457A
reads 10.0001, 10.0000, and 10.0005, respectively.

Soooooooo, what, if any, conclusions are reachable?  I am tempted to believe
that the 'black' face 731B and the 7081 are correct.  What are the odds?

Thanks in advance.

Joe