An original construction permit for low-power television station K64DR, channel 64, was granted to Broadcasting Systems, Inc. on August 23, 1989. The station was quickly built and was licensed on October 31, just two months later. It was affiliated with Telemundo and aired very little local programming. In December 1990, the station was sold to Hispanic Broadcasters of Arizona, Inc., and in 1996, when LPTV stations were allowed to acquire four-letter calls, they changed their call letters to KDRX-LP, which incorporated their original assigned calls, K64DR. In October 1997, KDRX-LP added a Spanish-language newscast produced locally by English-language ABC affiliate KNXV. They would begin producing their own newscast a few years later, after moving into KNXV's former Phoenix studio facility. The station was sold to Apogeo Television Phoenix LLC in 1999 and moved to channel 48 later that year, improving over-the-air reception. They became a Class A television station a year later when that class of station was approved by the FCC. The locally produced newscast and the move to in-core channel 48 helped them to qualify for the new status, giving them primary station protection during the digital television conversion of full-service stations, and guaranteeing them an opportunity to upgrade to digital TV. In December 2002, NBC Telemundo acquired KDRX-LP, and a few months later, changed its call letters to KDRX-CA to reflect its Class A status. However, Telemundo in Phoenix was up against one of the country's most dominant Univision outlets, full-powered KTVW. In 2005, Univision cornered 89% of the Spanish-language ratings in Phoenix, which was the last major market where it enjoyed such an advantage. In order to compete, NBC reasoned, the station needed to upgrade to a full-powered signal. Thus NBC filed an application with the FCC to move the license of full-power NBC Telemundo-owned KPHZ from Holbrook channel 11 to Phoenix channel 39. In exchange, Daystar-owned station KDTP would move from Phoenix channel 39 to Holbrook channel 11, and KDRX-CA would be transferred to Daystar in order to keep a Daystar Television Network outlet in Phoenix. It was an unusual request and complicated, involving not only a swap of licenses, but also non-commercial reservations in Phoenix and Holbrook, plus the 2 LPTV stations, but in October 2005, the FCC agreed to the proposal, over the objection of Univision. In June 2006, the station's license was transferred to Community Television Educators, Inc., while the intellectual unit moved to KTAZ. Later that month, KDRX-CA's call letters changed to KDTP-CA, reflecting the station's new owner, Daystar. The station continued to air Telemundo programming pending completion of new facilities for KTAZ, but changed its programming to the Daystar Television Network in July 2006 when the construction was complete. On February 4, 2008, KDTP-CA converted its Class A license back to a standard low-power license, likely because a Class A license requires local programs and the schedule for channel 48 was entirely the national Daystar schedule. No longer able to use the "-CA" suffix, and with "KDTP-LP" already belonging to its sister station on channel 58, the station changed its call sign to K48LK and then to KDPH-LP on March 1. The station also has a construction permit to build a digital companion on UHF channel 46, which it has designated as KDTP-LD.
