Greg wrote:

Hi,
I recently learned that VOR can be "calibrated" or adjusted to take
into account any error discovered at the 30-day check. For example, if
you need to set OBS at 44 to get centered CDI on the 42 radial from VOR
on airport checkpoint, and 219 to center CDI on the 222 radial, then
you record the errors: + 2 TO and - 3 FROM. Then, when flying an
approach, for example, outbound to the airport on the published 250
radial, you turn the OBS to the 250 - 3 = 247 radial and fly centered
CDI for more accurate approach. Sounds good to me and makes sense. Is
anyone doing it this way? Know of any good reference?
thanks
Greg

Flight inspection does just that for VOR final approach courses.

There is no FAA-approved procedure for pilots to further adjust for
individual receiver errors. (An IFR approach GPS solves all those
problems ;-)