Test USAC FX 680k trim with MX-A

3458A over USAC FX ref test, 2002's on MM MX after A-mod

Power: Keysight E36312A, +12.6, -12.6V

Reference levels:

Result CSV-data

Workflow:

* RPI accesses DMMs via GPIB and reads data.
* Data is formatted by python script into DSV string and written/append to file on FTP
* DSV-file is visible publicly on https://xdevs.com/datashort/
* Page http://xdevs.com/datalog_mm/ runs D3.js javascript library to read DSV file test.log to input data
* D3.js plots SVG graph online :)