[time-nuts] Assorted replies, and request for info

[Attila Kinali]

On Tue, 27 Feb 2018 06:58:04 -0500
ew via time-nuts <time-nuts at febo.com> wrote:

> Last year we did some work with a Tbolt and M100 using 40 000 seconds
> and 7 E-17 per uV. This was done with the support of Warren that I updated
> regularly. One set of data he responded on with: you are getting 1E-13 but
> what kind of Lab, 0.1 C over two weeks? The answer Juerg,s basement Lab in
> Switzerland while every body was on vacation. All critical tests are run
> over night.

In case you wonder what kind of basement this is, think of a German
style single-family home. Then add at +1 for sturdyness.. maybe even +2
and you are at how Swiss build their homes. Basements in Switzerland
are how other countries build their bunkers: Thick concrete walls.
Together with being underground (or semi-underground as in Jürg's case)
gives a very decent thermal mass and isolation. Having more than 5°C
temperature variation over a year in an (unheated) basement is unusual
and usually means there is something wrong with the building.

> What we now spend extensive time on is AC power. I have not seen much on time-
> nuts on this subject. Latest effort replacing vacuum fluorescents with LED 
> some thing I have not found in the US.

Be carefull with LED flourescent lamp replacements. You will replace
the 50/60Hz buzz with a 10-500kHz buzz that also tends to wander around
with time and temperature.

If you really want to have a quite light source, you have to build your
own LED lights, with properly filtered current sources. Nothing difficult,
but you have to design it properly because you are dealing with mains power.


			Attila Kinali
-- 
It is upon moral qualities that a society is ultimately founded. All 
the prosperity and technological sophistication in the world is of no 
use without that foundation.
                 -- Miss Matheson, The Diamond Age, Neil Stephenson