Homebrew is an amateur radio slang term for home-built, noncommercial radio equipment. Design and construction of equipment from first principles is valued by amateur radio hobbyists, known as "hams", for educational value, and to allow experimentation and development of techniques or levels of performance not readily available as commercial products. Some items can be home-brewed at similar or lower cost than purchased equivalents.
In the early years of amateur radio, long before factory-built gear was easily available, hams built their own transmitting and receiving equipment, known as homebrewing. In the 1930s, 40s, and 50s, hams handcrafted reasonable-quality vacuum tube-based transmitters and receivers which were often housed in their basements, and it was common for a well-built "homebrew rig" to cover all the high frequency bands (1.8 to 30 MHz). After WWII ended, surplus material (transmitters/receivers, etc.), was readily available, providing previously unavailable material at costs low enough for amateur experimental use.
Homebrewing was often encouraged by amateur radio publications. In 1950, CQ Amateur Radio Magazine announced a ‘‘$1000 Cash Prize ‘Home Brew’ Contest’’ and called independently-built equipment ‘‘the type of gear which has helped to make amateur radio our greatest reservoir of technical proficiency.’’ The magazine tried to steer hams back into building by sponsoring such competitions and by publishing more construction plans, saying that homebrewing imparted a powerful technical mastery to hams. In 1958, a CQ editorial opined that if ham radio lost status as a technical activity, it might also lose the privilege of operating on the public airwaves, saying, ‘‘As our ranks of home constructors thin we also fall to a lower technical level as a group’’.
In the 1950s and 60s, some hams turned to constructing their stations from kits sold by Heathkit, Eico, EF Johnson, Allied Radio's Knight-Kit, World Radio Laboratories and other suppliers.
Today, only a minority of hams own and operate completely homebrew or kit-built amateur stations. However, there are many new ham radio kit suppliers, and the "art" of homebrewing is alive and thriving.