Yes, it is the Armstrong Tower. This was the main and test site for the long
defunct Yankee Network of FM stations.

It is discussed in some detail in the book: " Empire of the Air".

Surely some Radio Club of America folks on this NG can drop us a few choice
trivia nuggets on the Armstrong tower:-)

Now, today's (related) quiz: where was (and what is located there now) the
"Wardenclyffe ' tower of Tesla fame:-)?
Hint: it's about 80 miles from the Alpine site.

73,
Chip N1IR