However, in August of that year he began an irregular series of broadcasts originating from his Cowen Park home at 5503 14th Avenue, N.E.

[11] A few months later Kraft applied for one of the new broadcasting licenses, which was issued on March 9, 1922, with the randomly assigned call letters KJR, for operation on both 360 and 485 meters.

Because there was only the single entertainment wavelength of 360 meters available for use by multiple stations, each region had to set up a timesharing agreement to allocate timeslots.

On June 23, 1922, three Seattle stations took turns operating from noon to 10:30 p.m., with KJR allocated 8:15 to 9:15 p.m.[17] In May 1923 the Department of Commerce set aside an additional band of transmitting frequencies,[18] and KJR was assigned to one of the lower power "Class A" frequencies, 1110 kHz,[19] which was modified a short time later to 1060 kHz.

On November 11, 1928, under the provisions of a major reallocation resulting from the Federal Radio Commission's (FRC) General Order 40, KJR was reassigned to a high-powered "clear channel" frequency of 970 kHz.

In 1925, it moved to the Terminal Sales Building, where Kraft had erected a 50-foot (15 meter) mast to serve as the station's antenna, which was soon superseded by a new, T-wire antenna built in North City near Lake Forest Park completed in 1927 (later the site of Saint Mark's Catholic Church), at which point the studios were moved to the Home Savings Building at 1520 Westlake Ave.[22][23] Kraft sold the station to businessman Adolph Linden in 1928.

[25] However, the effort failed and Linden and a subsequent owner, Ahira Pierce, were jailed for illegal financing, using money from financial institutions which went bankrupt.

The August 1941 adoption of the Federal Communications Commission's "duopoly" rule restricted licensees from operating more than one radio station in a given market.

[45] In 1957, the station was sold to entertainers Danny Kaye and Frank Sinatra, and Smith stayed on as general manager.

[47] In the 1960s, under the programming guidance of Pat O'Day, the station was top rated in Seattle and well known for introducing the Pacific Northwest to many recording stars such as Jimi Hendrix, the Beatles, Merrilee Rush and the Ventures.

[53][54] KJR's shift to sports programming was a gradual evolution starting in 1989, when the station added some sports-themed shows in middays and afternoons.

The rest of the music programming was phased out in September 1991, making KJR a full-fledged sports radio station.

[55] The co-owned FM station at 95.7 MHz, which Ackerley had acquired (as KLTX) in December 1987, eventually switched its call sign to KJR-FM (now KJEB).

During this time, Clear Channel did not transfer the KJR-FM call letters from 95.7 to 102.9, instead co-branding the station as "Sports Radio 950 AM and 102.9 FM KJR".

[60][61] KJR's listeners were entertained by some of the country's greatest radio personalities: Larry Lujack, Scotty Brink, Norm Gregory, Magic Matt Alan, Burl Barer, Pat O'Day, Eric Chase, Bob Shannon, Dick Curtis, "World Famous" Tom Murphy, Ric Hansen, Bobby Simon, Jerry Kaye, Gary Shannon, Ichabod Caine, "Emperor" Lee Smith, Lan Roberts, Kevin O'Brien (Kevin Metheny), Robert O. Smith, Charlie Brown, Bwana Johnny, Matt Riedy, Marion Seymour, Marty Riemer, Sky Walker, Tracy Mitchell, Bob Brooks and sports commentator Chuck Bolland, plus Bolland's much younger brother Mark "Jeffries" Bolland.

In 2002, Seattle Mariners relief pitcher Jeff Nelson had surgery to remove bone chips from his pitching elbow.

During his weekly show with Dave "Softy" Mahler, Nelson announced he would attempt to sell his bone chips on eBay.

After earning bids as high as $23,600,[62] eBay pulled the chips from auction for violating the site's policy of not selling body parts.

In 2003, Seattle Storm point guard Sue Bird made a bet with morning host Mitch Levy that gained national publicity.

[63] When asked at a later date, Tyler Orsborn (morning show producer at the time) suggested that Storm management were the real reason the bet was called off and not Bird.

[66] As of the 2018 Major League Soccer season, KJR is the English-speaking broadcast partner for Seattle Sounders FC with Matt Johnson on the call.

The deal also includes a promotional partnership with the entire iHeart Seattle cluster and the 80+ concerts and events to be held annually at Climate Pledge Arena.