[volt-nuts] Traveling Standards

[Bob Smither]

I have added more plots of the data taken by our fourth volunteer - so far over
a 3 week period.  The plots are posted here:

  http://c-c-i.com/ts

Somewhat unexpected, at least by me, was the drift observed the first week and a
half.  The two references (LM199A and MAX6350A) both drifted down several PPM.

The TS1 has been powered on for several thousands of hours - between being in my
lab and in the labs of other volunteers.  It was on 24/7 for almost 2 months
here before being shipped to the fourth volunteer.

The TS1 is shipped un-powered.

There is a large humidity difference between my location (high humidity gulf
coast of Texas) and the location of the volunteer (high altitude, low humidity).

There is also a significant pressure difference between the two labs.

The LM199A is hermetically sealed.

Although a small sample, the two references appear to be similarly affected by
whatever caused the drift - similar range of drift, similar time constant.

Details (schematic, etc.) about the TS are available at the above link.

Any ideas about what could cause the drift we are seeing?

Thanks!

-- 
Bob Smither                                             smither at c-c-i.com
=========================================================================
In all criminal prosecutions, the accused shall enjoy the right to a
speedy and public trial, by an impartial jury of the State and district
wherein the crime shall have been committed; which district shall have
been previously ascertained by law, and to be informed of the nature and
cause of the accusation; to be confronted with the witnesses against him;
to have compulsory process for obtaining witnesses in his favor, and to
have the assistance of counsel for his defence.
    -- Sixth amendment to the Constitution of the united States
=========================================================================
Circuit Concepts, Inc.                                       281-331-2744
-------------- next part --------------
A non-text attachment was scrubbed...
Name: smither.vcf
Type: text/x-vcard
Size: 140 bytes
Desc: not available
URL: <http://www.febo.com/pipermail/volt-nuts/attachments/20121017/f4e180c2/attachment.vcf>