|City||Rock Springs, Wyoming|
|Broadcast area||Rock Springs, Wyoming|
|Branding||99.7 Jack FM|
|Slogan||Playing What We Want|
|First air date||1978 (at 104.5)|
|HAAT||493.4 meters (1,619 ft)|
|Former callsigns||KMKX (1997-1999)|
|Former frequencies||104.5 MHz (1978-2005)|
|Owner||Big Thicket Broadcasting Company of Wyoming, Inc.|
|Sister stations||KRKK, KQSW, and KMRZ|
The station signed on as Sweetwater County's first and only Classic Rock station-"KSIT" in 1978 on a frequency of 104.5 FM. on Sunset Drive in the building that currently holds the Parole and Probation offices. In 1997, the station changed call signs to KMKX "The Mixx", playing everything from Classic Country to Rock. At this time, and for a time previous, Rick and Barb Mathis owned the station under the company name Sunset Broadcasting. Due to listener feedback and failing ratings, in 1999, the station returned to the KSIT call letters and the Classic Rock format. Some of the jocks during this period were Scotty August, Jammin' Joanie, Chillin' Chuck, Louie Louie, Brandon Keith, Ellie Woman and R.P. McMurphy. General managers were numerous as well. Charlie Reeves, Mark Kwiatkowski and Jason Jackson all held this position. Mark and Jason also served as Morning Show hosts.
Prior to 1999, the station was a competitor to KQSW/KRKK. Big Thicket Broadcasting acquired the three stations and KSIT was now a sister station. During her ownership, previous owner Barb Mathis ran the mixer board at times, but refused to talk on the air, which made for some odd radio. Barb has since died. Her husband Rick Mathis continues to run a local business, Copier and Supply.
One of the most beloved and listened to programs that dominated the noon to 1p.m. slot during the Sunset Drive years was Paul Harvey News and Comment. When Big Thicket Broadcasting bought KSIT, they moved Paul Harvey to sister station KQSW, angering many KSIT fans.
Ellie Woman started in April 1994 on Sundays from 6-midnight. After a month, she worked both Saturday and Sunday nights. She then moved to straight midnight-6a.m. shifts on weekdays for one month. She then moved up to 8p.m.-midnight, Monday-Saturday for a year. Then 3p.m.-8p.m. for a while and then for a few years did 9a.m.-3p.m. and always any shift needed in addition to that. She had the morning show for a year from 2006-2007. She had a very successful one-hour show during her 9a.m.-3p.m. shift called Lunchbox Rock, where she would showcase a classic rock band by playing songs from the artist as well as relating biographical information about the bands to the listeners. She held the positions of Program director and Music Director during her time as the Morning Show host. Ellie Woman has worked on and off at the station over the years and has covered the morning show for McMurphy as well as many other morning show hosts during absences. Ellie and McMurphy have crossed paths many times over the years, including Ellie working at a tattoo parlour McMurphy owned and ran locally in 1994-1995.
As of 2009, Johnny K. was the Morning Show host and played song requests along with his own personal favorites. He has held the positions of Music Director and Program Director. He was called to active duty with the National Guard and returned to his morning show slot after his deployment. Ellie Woman resumed her spot as morning show host in his absence. After Johnny K returned, Ellie would fill in on the morning show when he was unavailable. Johnny King's relationship with Big Thicket Broadcasting ended in mid 2009. He also worked for the competition in Green River, Wyoming.
On May 12, 2012 the owner of KSIT, Bill Luzmoor died.
On July 2, 2012, Sweetwater County native R.P. McMurphy returned once again for a 6th stint at KSIT. This is the 3rd time he has worked under the Big Thicket Broadcasting umbrella of KSIT ownership. He has done board operations for remotes and local and state sports broadcasts. He has done on site remote broadcasts as well as promotional stunts, such as dressing as a turkey and getting shot with paintball guns, dunking tanks and 80 foot free falls. He is the current Morning Show host, Music Director and Program Director. He started with the station in 1995 as the Midnight-6a.m. Weekend jock and moved up the ladder and time slots to become the morning host while the station was still located on Sunset Drive. He has worked on and off at KSIT over the years and after graduating radio school in 1985, made it his goal to come back and work at his local "Rock" station. He has held the positions of Music Director, Program Director and Production Director over the years. He filled in for many shifts for different jocks and sat in with Bill Luzmoor on sister station KQSW several times as well, playing "second banana". McMurphy has also worked for the competition in Green River, Wyoming as well as numerous stations across the country including an "all Elvis" station. He has recorded one single, "I Forget" as "Nigel Winkerdoo" under the band name "Nigel Winkerdoo and the Digital Neon Flying Sausages". It was played locally only on KSIT and never commercially released.
In 2005, KSIT moved its frequency from 104.5 to its current 99.7 MHz to clear the path for the Utah radio station KYLZ to move to 104.7 MHz and change its city of license to Lyman, Wyoming. The frequency change was funded by the owners of KYLZ. 3 Point Media, the owners of KYLZ sought bankruptcy protection in July 2007, prior to the new KYLZ facilities being licensed for operation.
Format Change to Jack FM
On May 31, 2016 KSIT changed their format from classic rock (as "Rock 99.7") to adult hits, branded as "99.7 Jack FM".
KSIT covers almost all of Sweetwater County and also has fringe coverage in parts of northern Utah, northern Colorado and southeastern Idaho. The station's broadcast tower is located on top of Aspen Mountain, south of Rock Springs. KSIT's tower is 8,648 feet (2,636 m) above sea level on top of Aspen Mountain.