WA2XMN 90 Years of FM Broadcast!
19 June 2025 - Noon-30 (EDT)

This broadcast was held in conjunction with the Society of Broadcast Engineers Chapter 15 summer picnic. Good coverage of the event on Radio World, SWLing Post, and TWiRT - This Week in Radio Tech (YouTube).

We had more than 25 reception reports. The most distant came from Mt. Greylock, MA, 122 miles distant.

Tim Martin WB2VVQ filed the following report:

There were 3 separate groups of us on Mt Greylock listening for the 90th commemorative broadcast of the first FM transmission by EH Armstrong on June 19, 2025, from noon to about 3 EDT. Latitude 42 deg 38 min 14 sec N, Longitude 73 deg 9 min 58 sec W, altitude about 3400 feet (we were not at the exact summit).

Sigurd KJ1K and myself had bad luck with a loop antenna and 1/4 wave whip, coupled with Icom 8500 and R20.

Peter K2AEP had good luck 59 report with hand held small receiver and whip, and also old low band Lafayette police band receiver.

Eric KA1SUN had excellent signal reception 59 with whip on his van with IC 8600 receiver. He recorded the whole broadcast.

We all very much enjoyed listening to the broadcast of the interviews. We are all big fans of Ed Armstrong. I belong to AWA, am on the board of directors, and am the editor of their annual book the AWA Review.

Here's a map of the closer-in signal reports:

Range rings are at 10 mile intervals.
Numbers refer to this document:

WA2XMN 19 June 2025 Signal Reports.


	Hearing WA2XMN: Transmissions are in wide-band frequency modulation using the same technical standards as modern FM broadcast stations. So, for optimum reception, you'd want an FM receiver with an IF bandwidth of about 200 KHz. This is a good time for collectors to wake up their "old band" FM radios. However, narrower receivers will be able to hear the signal. Scanners, military VHF sets (PRC-77 etc.), and the various modern wide-coverage receivers are generally up to the task. Select "FM" and the widest selectivity available. An improvised antenna such as a "twin-lead" folded dipole should do the trick. The transmitting antenna is vertically polarized, so orient your antenna the same way. In 2005 we had reception reports from as far away as 100 miles. You can review those reports here.