That programmer was me. (This is what happens when you let a non-pilot go poking at the nav code.)
The bug report was that a rather far away VOR could be received on the ground at KSFO; looking at the actual service volume, the notion that this could happen was crazy. I ended up tuning the distance calculation and also the "fudge factor". The fudge factor is the increase in the service volume of VORs in the sim from the listed usable service volume (which is really more like a guaranteed minimum) that lives in the nav.dat file.
Here's the real problem: VOR range has a lot to do with altitude, but X-Plane does not simulate shaped 3-d service volumes. I think we will, but probably not for 930. So for now we have to pick a fudge factor that is large enough to make IFR navigation work without allowing you to receive any VOR from any location.
Beta 3 is still a bit short for VOR range - beta 4 or 5 may improve things a bit.
Note that it is possible to change the service volume of navaids in the nav.dat file. For example, KBOS and KLAX both have extended localizers; the fudge factor for a localizer doesn't have to be 5x to allow KLAX to have a 100 nm final; the nav.dat entry for KLAX includes this special case.
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