In the quest for keeping my old stuff calibrated (or reasonably so), and
knowing many of us can't afford calibration services, or they simply aren't
available anymore to old equipment, I wish to setup some basic calibration
standards that can be counted-on without needing for sending them to
calibration services, so I ask your advice.
From what's currently available in the market, and some of you may know
1. What is a voltage reference IC (if any) that can be trusted
out-of-the-box, for calibrating, say, voltmeters in the 0.05% precision
range... or if not feasible, at least in the 0.1% range.
2. What is a good choice of resistor family (there are so many of them at
Digikey or Mouser that I simply can't choose) that can be purchased in
"hobby" quantities, in the precision range of 0.05% or at least 0.1%.
What's your advice regarding values and temp. coeff.? I was thinking of
values close to, but smaller than 2, and its multiples, like *say* 196,
1k96, 19k6, 196k, 1,96M and 19.6M. With 3 of each of them, it could be
enough to check / adjust voltmeters of 2000 counts, 4000 counts, 6000
counts and 10000 counts (20000 counts too, but it would require other
precision class for that).
And I know that it's usually not possible to adjust every range separately,
so it may sound overkill to have resistors to check almost all possible
ranges... but that's just my first "hunch".
Thanks for any tip and regards,