WSDF 100.5 FM logo (2020).PNG
Broadcast areaLouisville Metro Area / Kentuckiana
Frequency100.5 MHz (HD Radio)
Branding100.5 FM
FormatVariety Hits
SubchannelsHD2: K-Love
AffiliationsPremiere Radio Networks
First air date
1993 (as WTFX)
Former call signs
WTFX (1991-2002)
WTFX-FM (2002-2005)
WLUE (2005-2009)
WLGX (2009-2020)
Call sign meaning
SDF is the ICAO code for Louisville Muhammad Ali International Airport
Technical information
Facility ID53593
ERP37,000 watts
HAAT169 meters (554 ft)
Transmitter coordinates
38°11′32.00″N 85°31′17.00″W / 38.1922222°N 85.5213889°W / 38.1922222; -85.5213889
Translator(s)HD2: 95.1 MHz W236AN (Louisville)
HD2: 97.9 MHz W250BD (Louisville)
WebcastListen Live
Website100.5FM Louisville

WSDF (100.5 FM) is a radio station broadcasting a Gen-X/Variety Hits format under the branding "100.5 FM". Licensed to Louisville, Kentucky, United States, the station serves the Louisville area. The station is owned by iHeartMedia and features programming from Premiere Radio Networks.[1] The station is also broadcast on HD radio.[2] The station's studios are located in the Louisville enclave of Watterson Park and the transmitter site is in east Louisville, southwest of the I-64/I-265 interchange.


The station was assigned call letters WTFX on June 28, 1991. On April 19, 2002, the station changed its call sign to WTFX-FM, on August 19, 2005 to WLUE, and an application was filed as of September 3, 2009, to change the call sign to WLGX. On February 4, 2020, the call sign was changed to WSDF.[3]

This station initially signed on with a classic rock format on June 7, 1993, which shifted more towards mainstream rock and then active rock by 2002, as 100.5 The Fox.[4] On August 10, 2005, at Noon, "The Fox" moved to 93.1 and 100.5 began stunting with a loop of the songs "Louie Louie" by The Kingsmen and "Brother Louie" by Stories. At 2 p.m., 100.5 flipped to variety hits as 100.5 Louie FM. The first song on Louie was "Piano Man" by Billy Joel.[5]

On September 3, 2009, at 5 p.m., in response to slipping market share, the station shifted towards a 1990s pop/rock-centered offering called "100.5 Gen-X Radio". According to a press release which was issued hours before the format change, the station promised to feature music from "grunge, hip-hop, hair bands and boy bands".

Beginning in 2011, WLGX would temporarily drop their '90s Hits format beginning in November each year for a Christmas music format, branded as "Gen X-Mas", during the tenure of the 90s hits format. During these times, they maintained a separate stream of the regular "Gen X" format under the same name on iHeartRadio.

In April 2014, the station branding was modified and changed to "My 100.5 Gen-X Radio". At the same time, the 1980s and '90s music was greatly reduced, and the playlist was modified to include a Hot Adult Contemporary mix of music generally focused towards the 1990s through today. On July 1, 2014, at midnight, WLGX was officially rebranded as 100.5 MYfm.[6]

On May 25, 2016, WLGX rebranded as "100.5 Kiss FM".[7]

On November 27, 2019, WLGX dropped its hot adult contemporary format and began stunting with Christmas music; unlike other years the station had played Christmas music, the station had gone jockless with the flip, and had erased all references to "Kiss FM", rebranding as "Christmas 100.5".[8] At midnight on December 30, the stunting shifted to a broad-spanning variety hits format branded as simply "100.5 FM", teasing that a new format was "under construction", and was set to be revealed in the near future.[9]

On January 14, 2020, at 5 p.m., the variety hits format was confirmed as the permanent format, albeit with a slightly more narrowed approach consisting of '80s and '90s hits, not unlike the previous "Gen-X" format, branded as "100.5 FM - Your Life, on Shuffle". The first song under the new iteration of the format was "Bust a Move" by Young MC.[10]

Previous logos

WLUE logo.jpg
WLGX 100.5 MYfm logo.png
WLGX 100.5KissFM logo.png


  1. ^ "WSDF Facility Record". United States Federal Communications Commission, audio division.
  2. ^ "HD Radio Station Guide for Louisville". HD Radio. iBiquity. Archived from the original on 2016-10-29. Retrieved 2017-04-02.
  3. ^ "WSDF Call Sign History". United States Federal Communications Commission, audio division.
  4. ^[bare URL PDF]
  5. ^ "Louisville - 100.5 Louie FM - Variety Hits".
  6. ^ Gen X Growing Out Of Louisville
  7. ^ WLGX Louisville Relaunches as 100.5 Kiss FM Radioinsight - May 25, 2016
  8. ^ WLGX Drops Kiss FM For Christmas Radioinsight - November 27, 2019
  9. ^ 100.5 Louisville Goes Under Construction
  10. ^ "WLGX Brings Back Gen X Radio as 100.5 FM".