[volt-nuts] Datron 4000 DC/I/R Standard

[ed breya]

That seems like a nice piece of equipment if it works or is easily 
repairable. Why do you assume the displays are broken? If they used 
gas discharge displays, they would likely be Nixie or Panaplex type, 
which are pretty durable, and are still common enough to not be a 
problem with procurement. There is also plenty of data out there 
about these items and their drivers. The most common failures I have 
seen in these types of displays are bad digit drive transistors, and 
sometimes bad segment drive ICs - the tubes themselves usually don't 
just crap out, but gradually darken or fade out.

I don't know about the manuals, but if you do locate one in pdf form, 
please share it if possible - it's nice to have access to that info 
for reference material even without owning one of the units.

Ed