Greater didn't own WRKO or WEEI but there was some arrangement between the owners of those stations and 1150;
I do remember the incident where 1150 (WNFT) was briefly simulcasting WAAF and one day people realized it was now playing CHR/rap...the cleaning crew didn't like the rock that the "radio" in there was playing so they switched to 94.5,
unaware they were affecting what was going out on air!
history of 1150:
http://bostonradio.org/stations/25051
>>In May of 1997, WNFT was sold to American Radio Systems for an undisclosed amount of cash; the FM backup tower would be leased out by ARS affiliate American Tower Systems. On June 2, 1997, WNFT switched from simulcasting country WKLB-FM to ARS's hard-rock WAAF.
Read the paragraph after that to see ARS' merger with CBS led to the sale, afterwards, to Entercom due to the
ownership cap (Entercom bought 680, 850, 93.7, and 107.3 as a result of that)
This edition of NorthEast Radio Watch, from 1/1/98, explains the 1150 mix up
http://www.bostonradio.org/nerw/nerw-980101.html.
>>Johnson reports that the sudden change from WAAF (107.3 Worcester) to WJMN (94.5, owned by competitor Evergreen) was caused by the maintenance crew cleaning the transmitter site in Lexington. Seems the workers didn't want to listen to hard rock -- so they switched the dial to their favorite station, never realizing they were also giving WNFT listeners (if there were any) a dial twist as well. We'd have locked the radio up if we were running the place...