jack wrote:
Thaler has the best voltage references -- there was a design in one of the
rags (Nuts n Volts or QEX) a few years ago in which 3 Thaler references
were placed in parallel for a super reference. Email me privately if you
would like a copy.

Also, get a copy of Linear Technology Application Note 86 "A Standards Lab
Grade 20 bit DAC with 0.1ppm/degC Drift" -- Jim Williams is the author --
and make sure to read the appendices. Williams also did an ApNote with a
comprehensive history of voltage measurement techniques, but I forget the
application number.



Thanks for the suggestion. I must admit to never having heard of of
'Thaler', but a quick search has thrown up some really interesting
stuff. No online ordering, but an 800 number to find the distributors.
I'll follow up on that.

I'll get the LT AppNote. Thanks for the info.

73 Alf NU8I