Don't know, but a few times I've driven by the Blueberry Hill Healthcare facility on Brimball Ave. in Beverly and noted they have Companion Radio on 98.9; they did have early 60s or late 50s folk
on there one time, etc. So, rock and roll (early)? Maybe not necessarily; perhaps softer stuff like Peter Paul and Mary, etc. When I was visiting my Dad at the Danvers facility where he is, they had a replica of an old cathedral radio playing oldtime radio dramas, and I heard them say "this is
Companion Radio". I guess they have various types of streams and programming.
I do have XM radio and the decades channels begins with 40s; no 30s--don't know if 40s would get phased out eventually as people of a certain generation die off.
The companion radio site lists one stream/station as having "music from the late 1920s to the 50's".
Another: "Younger residents will enjoy this programming, which includes Country Showcase, '50s & '60s Jukebox, Easy & Relaxing Music and more." (Note that some people in their late 50s may be in
such facilities; dementia/Alzheimer's can strike younger people than you'd think). Another channel
is geared toward soothing music for Alzheimer's patients--all instrumental. Still another has one for the more active, including exercise classes, broadway music, etc. (companionradio.com )
As for the 88.7 signal, Fybush does mention in his column today that WSEW moved from 88.5 to
88.7 and doubled its power which could explain why some are suddenly picking it up (perhaps along the North Shore, as I did)
http://www.fybush.com/nerw.html