The 1340 AM frequency first signed on in 1944 as WNHC, under the ownership of the Elm City Broadcasting Company. Triangle Publications acquired the station, along with sister stations WNHC-FM (99.1 FM) and WNHC-TV (channel 8), in 1956.
WNHC was sold to Westerly Broadcasting Company in 1971. (Triangle had sold its stations, including the WNHC stations, to Capital Cities Communications; although it was able to retain what became WTNH-TV, it was forced by the Federal Communications Commission to sell WNHC and what became WPLR to comply with the ownership cap.) By this time, the station had a contemporary format; this gave way in 1976 to a middle-of-the-road/talk format.
WNHC again attempted a top 40 format starting in June 1979 in an attempt to complete against WAVZ; however, just weeks later, WAVZ swapped formats with its sister station, WKCI. With minimal promotion, WNHC struggled to compete with WKCI's stronger FM signal, and in March 1980 it flipped to an urban format. However, the station ran into financial problems during the 1990s, forcing owner Willis Communications to file for Chapter 11 bankruptcy in December 1997. The bankruptcy resulted in a battle between Yale Broadcasting Company, which wanted to eliminate a competitor to WYBC-FM, and Buckley Broadcasting over the sale of WNHC, as well as protests against Yale Broadcasting in New Haven's African American community. The dispute ended on June 3, 1998, when Yale Broadcasting purchased the station in bankruptcy court; the next morning, WNHC was shut down at the order of the bankruptcy judge. It returned to the air under Yale Broadcasting's control on September 15; on October 5, the callsign was changed to WYBC. (Starting in 1941, Yale students operated an unofficial AM radio station using weak-signal carrier current technology tolerated by the FCC and common among student-run stations at the time, renamed WYBC and changed to 640 AM in 1945, but that station ceased operations by the early 1980s, so the assignment of WYBC to 1340 AM caused no conflict.)
In the station's first decade as WYBC, unlike many radio stations on a college campus, it featured both student and non-student programming, some professional. However, interest in the station eventually dwindled (in sharp contrast, sister station WYBC-FM, largely programmed by Cox Radio, is one of the highest-rated urban adult contemporary stations in the country), and its college radio programming was transitioned to an Internet radio station, WYBCX, by 2010. WYBC then adopted its current public radio programming, provided by Sacred Heart University, on April 4, 2011 (WYBC-FM continues to operate as a commercial station). The station offers a distinct program schedule from other Sacred Heart University-operated stations (such as WSHU-FM and WSUF); consequently, WYBC is one of the few NPR news/talk stations to not carry All Things Considered (which is heard on WSHU's other stations), and initially the station also did not carry Morning Edition. The time brokerage agreement with Sacred Heart University provides funding for WYBCX's operations.