The Experimental Station WA2XMN on 42.8 MHz

In 1933, frequency modulation or FM radio was invented by Edwin H. Armstrong in the USA to reduce the static and interference associated with AM transmissions.

In June of 1936, Armstrong established the experimental station WA2XMN at Alpine, New Jersey and began experimental FM transmissions with a 40kW power level in the 42 to 44 MHz band.

After the second world war, the FCC moved the FM band up to 88 to 108 MHz and this is the one we are familiar with today.

To commemorates the pioneering broadcasts of the world's first FM radio station, WA2XMN occasionally broadcasts on a frequency of 42.8 MHz. This was one of the frequencies used by Armstrong's station on the original FM broadcast band.

The station broadcasts with a power of 250 watts from the same Armstrong Tower in Alpine, New Jersey. When it does broadcast, the FM signals have been heard by radio enthusiasts within a 160km / 100 radius.

The QSL card at the top of the post was sent out for a transmission in April of 2018.

I'm not sure when the last broadcast was but it would be interesting to hear of any future transmissions.

Links...
1) WA2XMN website with reception reports
2) Email archive about test transmissions