Metrology Meeting 2024 in Stuttgart/Germany - The finale

[Sprock]

Pic MM2024 all Ziped.

Sprock

[Dr. Frank]

Hello Sprock,
Zip_3 attachment is missing!
Maybe too big?

Anyhow, many thanks for the pictures
Frank

[Sprock]

Thanks for Info

[branadic]

Thanks for sharing the photos. To also share some numbers, I've taken some measurements on Sunday after MM2024:

F7000-1 drifted from 9.9999807 V (measured on 26. Nov. 2020 at xDevs.com) to 9.9999271 V (18. Aug. 2024) --> delta: -53.6 µV in 1361 days
F7000-2 drifted from 9.9999918 V (measured on 26. Nov. 2020 at xDevs.com) to 9.9999739 V (18. Aug. 2024) --> delta: -17.86 µV in 1361 days

That's -14.37 µV/year for F7000-1 and -4.79 µV/year for F7000-2, which agrees with the diagrams I presented at MM2024 showing a larger drift for F7000-1. The huge drift for F7000-1 might explain why it was sold back in 2020. I remember Frank reporting excess drift on his F7000-3 too, but I currently don't know the drift of W7000, that came with F7004T.

-branadic-

[Okertime]

Here are some measured differential voltages to my Fluke 732B over time:


                  MM2021            MM2022            MM2024

F732B              0                     0                      0

F7000-1       -30.4 uV          -43.0 uV           -63.4 uV

F7000-2         -7.0 uV          -13.4 uV           -17.2 uV

W7000         -11.1 uV          -12.6 uV           -25.6 uV

F732A ron                          -?11.9 uV          +27.0 uV

[Sprock]

Here we go.

W7000 from Nov 2020  -->  9,999991 V

W7000  at MM 2024      --> 9,9999619 V

as temperature was around 28°C this is for me a bit questionable.

should doing this again under better condition.

anyway lot´s of fun

[Roehrenonkel]

Hi,

the photos i took are basicaly the same as from Sprock.
If anyone is interested in the whole set i can send a "wetransfer.com"-link to your e-mail.

Best regards

[iMo]

Is there any info how the Z10 is made?
An ovenized Jfet Vref(s) with a Chuck's "opamp noise thread" winner as the buffer? 

[BU508A]

Is there any info how the Z10 is made?
An ovenized Jfet Vref(s) with a Chuck's "opamp noise thread" winner as the buffer? 

No technical details have been revealed. It is still a magic box with lots of coloured charts.

[MiDi]

Big thanks for the wonderful meeting, sad that this was the last meeting in this form 

A bit late to the party, but here are my results:
LTZ#3 as brought:                                  7.1006285V ±0.30ppm
as measured by Dr. Frank:                      7.1006253V ±0.42ppm (-0.40ppm)
as measured by 732B from Okertime:     7.1006324V ±0.5ppm  (+0.55ppm)
as measured by F7000-1 from branadic: 7.1006282V ±2ppm     (-0.05ppm)
as measured by F7000-2 from branadic: 7.1006286V ±2ppm     (+0.01ppm)
as measured by 3458A from branadic:    7.1006344V ±2ppm     (+0.82ppm)