The company known today as Zenith was founded at a kitchen table in Chicago in 1918 by Karl Hassel and Ralph H. G. Mathews. In 1919, Hassel and Mathews moved their operations into a 14-by-18-foot garage, where they formed the Chicago Radio Laboratory (CRL). They used half of the garage to make hand-engraved radios out of Bakelite and the other half for their amateur radio station, 9ZN.

That same year, the Chicago Radio Laboratory began placing advertisements for its products in “QST,” the American Radio Relay League’s Magazine. One of CRL’s employees suggested that 9ZN be listed with a small “ith” after it. 9ZNith soon became Z-Nith.

In 1921, CRL moved into a 3,000-square-foot factory in Chicago. In early 1922, the company was making five radios each week; by June of that year, it was making 50 per week. With investment money from Eugene F. McDonald, Jr., Hassel and Mathews founded the Zenith Radio Corporation in 1923 as a marketing division for CRL. A few years later, the two merged and both manufactured and advertised under the Zenith name.

Zenith quickly became known as an innovator. It released the first portable radio in 1924, followed two years later by the first radio that operated entirely on household electricity. In 1927, Zenith introduced the first radio with push-button tuning, and in 1940 it broadcast the first FM radio station in the Midwest. In fact, Zenith co-invented the FM stereo broadcast system, which was authorized by the FCC in 1961.

Zenith expanded throughout the 1920s. In 1927, the company debuted its now-famous slogan, “The Quality Goes in before the Name Goes On.” The company also helped found the Consumer Electronics Association, and Zenith’s CEO was the first president of the National Association of Broadcasters.

With the coming of the Depression, Zenith was forced to change its focus from high-quality radios to more affordable ones. Following the lead of Philco’s Baby Grand, Zenith released its own cathedral radio, the moderately successful Zenette Model L, in 1931. Like many of Zenith’s other radios of that era, the Zenette featured an Art Deco design.

Zenith also produced chairside and table models, many of which had a handle on top to make them even more portable. The company’s 500H was considered the highest-quality portable...

During World War II, Zenith made bomb fuses and other devices for the government. Afterward, the company shifted gears and devoted most of its attention to televisions. Here, too, Zenith became an innovator, releasing the first wireless remotes for TV in 1955 (the Flash-Matic) and 1956 (the Space Command).

Collectors of Zenith radios can use model numbers to help identify a radio’s model year. From 1930 to 1935, each radio had a two- or three-digit model number; in general, larger number models were made later in this five-year stretch.

Starting in 1936, Zenith’s radios had a much more descriptive six-digit model number. The 6-S-646 is a good example of the typical format. The first 6 indicates the type of vacuum tubes in the unit (this figure could be one or two digits). The S indicates the capabilities of the model; D, for example, meant the model had AC/DC power and only received the broadcast band, whereas S usually meant that the radio was AC-powered and also received one shortwave band.

The first number of the last three digits indicates the model year. The number 1 corresponded to 1937 model radios, 2 corresponded to 1938, and so on (if this number was missing, that indicated a 1936 model year). Finally, the last two digits indicated how deluxe the model was, with lower number models generally having fewer features than models with higher numbers.

In 1950, Zenith switched to a four-digit model-number system. The first letter indicated the model year, with G corresponding to 1950, H corresponding to 1951, and so on. The three digits afterward were somewhat arbitrary.

About our sources | Got something to add?

▼ Expand to read the full article ▼

Best of the Web (“Hall of Fame”)

Zenith Stratosphere: Behind The Dial

Zenith Stratosphere: Behind The Dial

David Wilson’s handsome site is obsessed with Zenith's top-of-the-line 1934 console radio, which cost a whopping … [read review or visit site]

Jim's Antique Radio Museum

Jim's Antique Radio Museum

Jim Tripp's showcase of radios from the 1920s to late 1950s, organized by style and theme (wood, console, plastic, … [read review or visit site]

The Radio Attic's Archives

The Radio Attic's Archives

This photo gallery of over 7800 vintage radios, categorized by manufacturer and model number, is a group effort wit… [read review or visit site]

Alan Voorhees' reference resource for vintage radio collectors includes a photo gallery, article library, PDF archi… [read review or visit site]

This vast archive and community of radio collectors features over 120,000 radio model listings and 350,000 photos a… [read review or visit site]

Phil's Old Radios

Phil's Old Radios

This extensive collection of antique radios includes beautiful photos and detailed historical descriptions. The sit… [read review or visit site]

John Pelham's collection of wood and plastic radios from the 1930's and 40's. What sets this site apart is the deta… [read review or visit site]



Steve Erenberg's extremely wacky and well-done collection of vintage mad-scientist devices and contraptions. Writte… [read review or visit site]

Clubs & Associations

Discussion Forums

Other Great Reference Sites

Most watched eBay auctions    

Zenith 10s160 Console RadioZenith 880 Console RadioSharp Looking Prewar 1941 Zenith Bakelite Tube Radio -fully Restored Antique GemZenith 1930s Antique Vintage Art Deco Tude Radio Console Chair Side Chairside Amazing Zenith 7s529 1941 Black Dial RadioZenith Model 5s56 Black Dial Art Deco Console Radio #slotted Grill #wood Knobs Zenith Model 6j230 Wood Tombstone Tube RadioAntique Zenith RadioBeautifully Restored Zenith Tube RadioZenith Radio Gorgeous Mid Century With Clock M-5j03 Restored Vintage Deco 5 Tube1946 8h034 Zenith Am/fm Tube Radio Excellent And Working No Reserve1940s Vintage Wood Zenith Deco Tube Table Radio 6d030 Z Eames ? Boomerang Old Antique Wood Zenith Vintage Tube Radio -restored Working Classic Table ModelVintage Zenith Radio Model 7s529 Table Model ShortwaveNear Mint Antique Vintage Zenith Y723 Old Tube Radio Works Perfect - See Video!1937 Zenith 5r236 Chairside Radio With Magazine RackVintage Zenith 6d525 Wood Tube Radio 1941 Ingraham Long Distance RefinishingZenith Rd7000y Trans-oceanic - Time Capsule Condition!!!Early 40's Antique Zenith Radio 6-d-630 Working Condition!Zenith Bakelite Radio Model 6d311 C 1939 Vintage 1950's Zenith Wood Am/fm Tube Radio Serviced And Plays Outstanding!1930's Zenith Console 7s258tube Robot Dial RadioGood General Electric 1l6 Radio Vacuum Tube For Zenith Transoceanic Radios & BoxRestored, Near Mint Antique Zenith Vintage H845 Old Tube Radio Works -see Video!Vintage Zenith 15-u-270 Speaker, Acoustic Adapter, And 4 Speaker Posts Rare Vintage Zenith 7h822z Am/fm Radio In Flawless Cabinet Works W/ No Hum!!Vintage 1951 Zenith Trans-oceanic H500 Tube RadioZenith Transoceanic 7000 Zenith Antique Vintage Old Wood Tube Radio Boomerang DialZenith Mj1035 Tube Radio Plus Left Channel Speaker Am Fm Phono Works Great!Working Vintage 1956 Model Y723 Zenith Bakelite RadioLot (3) Vintage Motorola Custom Eight Zenith Royal 50 W/ Casetransistor RadiosZenith - Model 6d-525 With Top Handle ! L@@k !Zenith Royal 500 E With Box Case Instructions And Ear Phones Not WorkingZenith 6d510 Radio, Nearly Flawless, Plays Well!Zenith Am/fm Wood Tube Radio Md: M730 1960's Works Excellent Mad Men EraAntique Zenith Cabinet Radio Am/fm High Fidelity Tube Space Age Model A835Vintage Zenith Trans Oceanic Radio R3000-1 W Box Manual & Power Supply Works1930's Zenith Console 7s258tube Robot Dial RadioVintage Zenith Transoceanic | Trans-oceanic Tube Radio - WorksVtg Zenith Long Distance Tube Radio Multibrand Standard Foreign Black DialVintage 1960's Zenith Royal 500e Transistor RadioVintage 1952 Zenith - Table Radio - Am - Bakelite - Works Great - Model # K510yVintage Zenith 500d Long Distance Transistor Radio - It Works!!!1953 Zenith Telechron Alarm Clock Tube Radio Brown Model 6l03 WorksOld Zenith Bakelite Tube Radio ~ Super!Zenith Radio Gold Textured Look Tube Shields 5 5/8 Inch Great Condition! 1940'sIndiana Attic Find-vintage 1952 Zenith Bakelite Tube Radio Model H615zGreat Looking Zenith Wood Tube RadioVintage 1959 Zenith Transistor Radio In Rare Color In Original Box , No Cracks Zenith F615 Antique Vtg Tube Radio Mcm Sounds Incredible! Near Mint Mad MenVintage Zenith Royal 285 Transistor Radio Am Tested And Working Take A Look !!!Vintage Zenith Transistor Radio - Royal Eleven - Pocket Size RadioZenith 10s464 Chassis With Tubes And Esheon Zenith Radio 1940 10-s-464 Dial Faceplate With Glass And Pointer Exc Condition 2 Decent Bright 6e5 Eye Tube F/ Old Ham Radio Receiver Tuner Zenith Audio AmpZenith Am Fm Model K731 Long Distance Tube Radio 35 Watts Works NicelyVintage Zenith All Transistor Trans - Oceanic Royal '1000-d' Radio ^Vintage Bakelite Zenith Radio ~ Model 7g013 Zenith Transoceanic D7000