✏Henry Herman's station originally broadcast using a 5-watt transmitter. In 1924, it boosted its power to 100 watts. On October 4, 1924, Henry Herman transferred KZKZ's ownership to the Radio Corporation of the Philippines (RCP), which he himself organized.[4][3] In 1926 the company began to work on constructing two of the largest radio stations in Asia with the idea of maintaining direct Manila-San Francisco service.[5] After Philippine independence, it changed its callsign to DWKZ, but changed in 1960 to DZCA.[6]
✏In 1929, RCP launched KZRC in Cebu broadcasting with a 100-watt transmitter, but was later sold to store owner Isaac Beck. It is now DYRC owned by the Manila Broadcasting Company.[3]
✏Early on, all radio programs were in English.[3] This was the American Colonial Era in the Philippines. Most shows resembled American shows, even copying sponsorship.
✏Radio was unregulated until 1931 when the Radio Control Board was established under the Insular Government
✏The current oldest continuously operating radio station is DZRB-AM,[7] which began life on September 3, 1927 as KZRM.[8] Another old station would be DZRH, started as KZRH.