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 Radio Pristine Bakelite Pancake M-6d-312 Ebony Beauty Working Condition!Zenith 12s266 Console RadioZenith Tombstone Radio Model 5-s-29Vintage 1941 World War 2 Zenith Old Shortwave " Bomber " Transoceanic Radio 1938 Zenith Cube 6-s-222Zenith Royal 1000 Vintage Trans-oceanic Am-shortwave Multiband Radio ~ Exc Cond.Old Zenith 3 Band Black Dial Wood Tube Radio ~ Nice!Vintage Federal Jr. (junior) Crystal Radio Old Rare Antique Tube Crystal Zenith Vintage Wood Case Zenith Art Deco Tube RadioZenith Model 481 Radio/phonograph - Original Zenith 7s260 Console RadioAntique / Old Vintage Zenith Model 8h034 3 Band Tube Radio Original Estate Cond.Vintage Zenith Transoceanic Radio G500, WorksZenith Model R511v... The Hollywood...!!!!!!!!!!!!!!!!!!!!!!!!!!Zenith Model 705 Wood Table Radio C 1934Vintage Bakelite Zenith Am/fm Tube Radio Model H725-restoredVtg: Ultra New Zenith Royal 7000y-1 Trans-oceanic Portable Radio 1962 Zenith Royal 50 *black* With Case -- Works GreatAntique Zenith Trans-oceanic Fully Restored, Cabinet Also! 8g005yt Model1962 Zenith Royal 50 *gray* With Case -- Works GreatZenith Royal 500 "owl Face" Transistor Radio Black/gold - 1st VersionVintage Zenith J733 Tube Type Clock Radio Zenith 6d314 Deco Bakelite Table Radio Tube Vtg Antique Works Brown Art GoldOld Vintage Zenith Rd7000y Trans Oceanic Transistor Radio Solid State ReceiverVtg Antique Zenith Model 705 Wooden Wood Cabinet Vacuum Tube Table Radio 1934 NrVintage 1942 Zenith 6d615 Consoltone "boomerang Dial" Bakelite Tube Radio ~rare~Zenith Transoceanic 8g005 - "clipper" - "good Solid Condition!"Zenith 7s633 Antique RadioZenith 6s330Zenith Royal 1000 Vintage Trans-oceanic Am-shortwave Multiband Radio ~ Exc Cond.Zenith Transoceanic Radio - Model B600 - (starts $9.99)Zenith 500d "long Distance" Am RadioGeorgous Pre-war Zenith 6d644 Boomerang Black Dial Wood Radio Restored WorksVintage Bakelite Zenith Tube Radio Model R721 - Works1950's Zenith Trans Oceanic Royal 1000 Wavemagnet All Transister RadioZenith 7h822 Bakelite Table Radio Tube Am / Fm Works Retro Space Age Deco VtgClassic Zenith 7h822 Bakelite Table Top Radio Am / Fm Art Deco (works!)1964 Zenith Royal 810 Transistor Radio ~ Zenith's 1st Handheld Fm PortableZenith Deluxe 5j03 Telechron Radio Owl Eye Bakelite Antique Tube ClockZenith Trans-oceanic B600l Brown Leather ~ *no Reserve*Vintage Zenith Wavemagnet Trans-oceanic Tube RadioVintage 1950's Zenith Model X334am Fm Long Distance Tube Radio - Nice ConditionZenith Am Short Wave Receiver Model M660a Works! Vintage Radio Vintage Zenith Clock Radio Snooz-alarm Model C519l TelechronZenith Grey Table Radio Model A615g For Parts Or RepairVintage Zenith Universal Radio 6g001zy1, WorksVintage Zenith High Fidelity RadioZenith 12" Inch 49-148-ab Speaker For Radios With Acoustic AdapterVintage Zenith Model X323 Tube Working RadioVintage Zenith Royal 500d Transistor Radio 1958 Ch= 8at40z2 Owl Eyes Works Rare1960's Zenith Am Transistor Radio1951 Zenith Plastic Radio, For Parts Or RestoringBig Pile Mix Loktal Tubes F/ Old Ham Radio Philco Zenith Receiver Tube Audio AmpVtg Art Deco Tube Antique Table Radio - Zenith Clock Radio L622 Mint GreenVintage Zenith Floor Model Radio/phonographAntique Vintage 50s 60s Bakelite Zenith C725c Bakelite Am Fm Tube Radio - Works1962 Zenith Royal 50 **beige** -- WorkingVintage Zenith Long Distance Tube Radio Model- 6goo1yRca 3v4 Audio Power Penode Tube Nos W/ Carton Zenith Trans O & Portable RadiosZenith Stereo Cd Alarm Clock Radio