WYHI (99.9 MHz) is a non-commercial FM radio station licensed to Park Forest, Illinois, serving the Southland suburbs of Chicago.

It is owned and operated by the Bible Broadcasting Network and it carries a Christian talk and teaching radio format.

National religious leaders heard on WYHI include Chuck Swindoll, Joni Eareckson Tada, Adrian Rogers and J. Vernon McGee.

The transmitter was located 2.9 miles north of the city limits, and it had an effective radiated power (ERP) of 6,600 watts at a height above average terrain (HAAT) of 210 feet.

[6] In the 1960s, the station aired a beautiful music format, with mostly instrumental cover versions of popular adult songs.

[9] In late 1974, Claude Baker and Luella Feller sold the station to Harry Fitzgerald, Howard Dybedock, and Benedict Cerven, Sr. for $132,315.

[5] In 1979, the station's transmitter was moved to Peotone, Illinois, along the Kankakee County/Will County border, and its ERP and HAAT were increased to 50kw and 500 feet respectively.

[11][12][13][14] In early 1984, Harry Fitzgerald, Howard Dybedock, and Ben Cerven sold the station to Gene Milner Broadcasting for $1.2 million.

[29] "The Bus" branding would return to a CHR station in the area in 1998, on 100.7 WBVS in Coal City, Illinois.

[37][40] In June 2004, Newsweb launched an adult hits format on the station, branded as "Nine FM", with the slogan "We Play Anything".

[46][50] After the station's sale to Bible Broadcasting Network, Polski FM briefly moved to WMFN AM 640.