Homebrew 8 1/2 Digit DIgital Voltmeter (DVM)
Hackaday: Homebrew Metrology The CERN Way.
https://hackaday.com/2021/02/26/homebrew-metrology-the-cern-way/

Jim Bell's note:. In 1974, one of my early electronics projects was to design and build a 4 1/2 Digit DVM, including a custom-designed printed circuit board that I laid out and etched.

It used a MK5002 counter chip. 
 https://www.datasheetarchive.com/?q=MK5002