Within what distance must an amateur station protect an FCC monitoring facility from harmful interference?
A. 1 mile
B. 3 miles
C. 10 miles
D. 30 miles
The answer is: A. 1 mile.
Why? Because the FCC has said so, basically. In section 13 of Part 97.
(b) A station within 1600 m (1 mile) of an FCC monitoring facility must protect that facility from harmful interference. Failure to do so could result in imposition of operating restrictions upon the amateur station by a District Director pursuant to §97.121 of this part. Geographical coordinates of the facilities that require protection are listed in §0.121(c) of this chapter.