Denny wrote:
We have had regulation of RF emissions since 1912... I have been an
active ham for 45 years... I have read most of the back issues of QST
over the years, clear back to the start.... I keep up (mostly) with
regulatory and enforcement actions that affect hams....
Never, ever, have I run across an action by the FCC against a ham for
using a piece of test gear that radiates low power signals...

Perhaps not against hams, but cases of FCC enforcement actions against
commercial users of test equipment have occurred. A typical case is
radiating on an antenna test range with a bit too much power, or without
the necessary experimental Part 5 license. There are also cases of
companies getting tagged for doing things like testing a radar, but
that's something designed to radiate, not a piece of test gear.

The general rule is, if they can't detect it at the property line,
you're probably legal.