WGU-20 logo. Wikipedia image.

Forty years ago, the Spring-Summer 1976 issue of Communications World carried an interesting profile of station WGU-20, sometimes dubbed “the last radio station.”

The station was built at a cost of two million dollars in 1973, and operated with a power of 55 kW on 179 kHz with a 700 foot toploaded vertical antenna located at Chase Maryland. It was operated by the Defense Civil Preparedness Agency.

The station was designed to be the first in a network of longwave stations constituting the Decision Information Distribution System (DIDS) to warn the public of an enemy attack. An additional stations, operating on 167, 171, and 191 kHz were to blanket the continental United States with coverage, controlled by 61.15 kHz control stations at Ault, Colorado, and Cambridge, Kansas. In the event of an attack warning, civil defense authorities would send the alert to these control stations by landline or microwave, and the DIDS network would commence playing taped messages warning the public.

The station did QSL, and the magazine provided the mailing address for reception reports.

The network was never built, and the WGU-20 antenna was ultimately demolished in 2011. While it was operational, the station broadcast the time of day:

Good evening. This is WGU-20, a defense civil-preparedness agency station, serving the east central states with emergency information. Eastern Standard Time seventeen hours, twenty minutes, twenty seconds. Good evening. This is WGU-20, a defense civil-preparedness agency station, serving the east central states with emergency information. Eastern Standard Time seventeen hours, twenty minutes, thirty seconds. Good evening. …

The video below contains a recording of WGU-20, and was recorded at a later date after weather broadcasts were included in the broadcast: