Coaxial cables and RCA cables share many attributes. At the heart of it, they're both two-conductor cables with connectors on the ends. Although the connectors differ, it's easy to convert an RCA cable to a coaxial cable through the use of special cable connector adapters. This could be useful if you want to take advantage of the signal transfer and electronic shielding of a high-quality RCA-style cable for an application that requires coaxial-style connectors.
Make sure that the RCA cable you'll be converting is long enough to make the connections between the electronic components you want to hook up. It won't do you any good to convert the cable if it's not long enough for the job!
Purchase adapters. You'll want adapters that convert a male RCA connector into a male "F type" coaxial connector. The F type is the most common coaxial connector and is invariably the type of connector that is used on coaxial cables in home video applications. You can find these at electronics supply stores. They are also available online.
Connect one adapter to each end of the RCA cable. The adapters will slip snugly onto the cable's RCA connectors; no tools are required. Your cable is complete.