From the QSL (response to a reception report) I received ...

... Dear Listener,

Thank you for your report of reception of the Armstrong 70th Anniversary
Broadcast from WA2XMN on 42.8 megacycles. The attached file contains an
electronic QSL card. If you print it out, it will be a good fit for a
5-by-7-inch frame. The second file contains all of the reports received.

Keep an eye on the website for information about possible future
transmissions.

Best regards,
Al ...

Background ...

Major Armstrong's Tower
https://njpalisades.org/majorarmstrongstower/

... Tucked in the woods west of bustling Route 9W in Alpine is the Armstrong Tower, a three-armed steel structure rising 425 feet into the sky. While the tower is a prominently visible landmark within an area encompassing hundreds of square miles -- in New York, New Jersey, and Connecticut -- few who see it are aware of the story behind the tower or the man who built it.

Edwin Armstrong was born in New York City in 1890. When he was twelve years old, his family moved to Yonkers. Throughout his childhood, Armstrong, who read up on inventions and experimented with radios, sought to make improvements on the quality of sound transmitted by radio signal. As a junior at Columbia University, Armstrong achieved this goal in part when he invented the regenerative-oscillating circuit, an innovation that helped pave the way for transatlantic radio telegraphy. ...