here. Presently WKDU is a college radio station owned by Dexel University in Philadelphia, PA. As with all things, it had a beginning, and in the beginning there was no such thing as 91.7 WKDU. It began as a carrier current station with the informal callsign WMAX. Most sources date it's debut to 1958. In 1962 they switched to cable on 830AM as WXDT. It began broadcasting in 1970, but it's transition to FM came only from the fall of another station, and the defeat of another. There was a battle royale for the 91.7 frequency and WKDU was the last station standing. More here.
But there was a third station in this tale. WPWT was the radio station of Philadelphia Wireless Technical Institute (PWTI), hence the call letters. It was located at 1533 Pine St right in Philadelphia. PWTI had been operating since 1908 and is post-worthy on it's own. It wasn't a large school, though it was accredited by the National Association of Trade and Technical Schools (NATTS). It was lost accreditation in 1998 and no longer exists. [More here] PWTI had signed on WPWT in December of 1949, (originally on 90.1.) The book Philadelphia Radio by Alan Boris reports this as 1950 but it's sign-on is even clearly described in the November 1949 issue of Billboard as "earlier this year." They were the second FM station in Philadelphia which is quite an achievement.
But by the 70s it had perhaps 60 students at any given time. With a small student body it can be hard to maintain a station. So in about 1972 they began a share time arrangement with WXDT to keep the lights on. To share time The Drexel kids needed a real callsign to share time so they became WKDU with just 10 watts. They split the week with the 180 watt WPWT operating from 2:00 PM to 10:00 PM daily, and by all reports, the format was Disco. In the early 1980s they segued to Top-40. In 1981 WKDU gets FCC thumbs up to jump from 10 watts to 110 watts, escaping the confines of their Class D license. Spontaneously WPWT developed much better taste in music and began broadcasting a metal-centric playlist similar to WSOU.
WEXP were halted for a few years. and it's schedule was erratic. But the station united in 1988 in an attempt to purchase the now ailing WPWT. Ultimately this was rejected by the University Budget Committee.Full stop. This immediately follows the first year that WKDU won "Best of Philly" Radio Station from Philadelphia Magazine. Ouch.
WEXP still exists today, but only online. Had they succeeded in buying the then 250 watt WPWT license, this story would have ended very differently. Perhaps WEXP would be a share-time with WKDU, or perhaps they would have won out entirely with Drexel students drifting away from the then puny 110 watt WKDU. Instead, in 1988 WKDU went stereo and WPWT ceased operations with WKDU buying out their side of the license. In1996 WKDU got the nod from the FCC to increase power to 800 watts... as reigning champion.