One who did not build own calibrator from random crap cannot be called true volt-nut.
Back in 2014, when I was naive and overly optimistic, I thought it would be piece of cake to build a DIY MF-calibrator. There is still
a thread as evidence of that. Fast forward to 2018, I've learned quite a bit, build over 30 LTZ1000-based references, accumulated lot of expensive not-necessary equipment and even got somewhat working
5.5-digit Time Electronics 9823 calibrator.
However friend of mine introducted me to real deal, Fluke 5700A, and since we peeked inside
of it my soul was gone.
Only owning very personal 5700A can restore the status quo. As with usual volt-nut disease, first sign is suddle - I thought why not buy A11 REFDAC board from 5700A, that will give me finished and proven dual LTFLU-reference and DAC eh? Just add some RPI, power supply and level translation, some python code, and we can get module to generate some precision voltages, eh?
Well, shortly after I got ohm boards.... then I discovered that to power these things I will need about 6 different unipolar rails. Well, after XXXX $$$ spent over last 2 years I have now all 5700/5720A boards, some in multiple quantity. I even scored Fluke 5500A front panel, which I hope to modify to fit 5700A VFD display board.
Today I received last bits - A3 and A4 backplanes, so this project is to kick off from waste of moneys and dust collectors to hopefully something workable.
Now the only "issue", I don't have a chassis. So far my best thinking is to make CNC plates from Aluminum and build something like a crate to hold all things together, in arrangement same as real-deal 5700A.
Who need chassis anyway, eh?
To be continued.
First I need to restore cables with connectors on transformer and check baseplane boards and outguard power. Then we can continue to inguard power and then start adding boards as progress goes.