WSRO-AM at 650 on your dial, yesterday became the first AM station in New England to convert to the digital HD format, the folks at the Boston Radio Interest mailing list report.
If you have a car or plain old radio that gets HD signals, tune to 650 and, like magic, the little HD icon will light up, like it usually does on FM but never did on AM.
The change will supposedly mean better quality reception - no more static - for the station's current jazz and 30's-era music.
But unless you're in MetroWest, be prepared for the station to suddenly disappear on you at night if you pass by a hill or large building between you and the station - which drops its power output at night. Unlike traditional AM, which slowly degrades, digital signals are sort of all or nothing - either it comes in really well or, boom, not at all, at least until you get out from under, oh, the West Roxbury Parkway side of Bellevue Hill in West Roxbury.