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    

Old Antique Wood Zenith Vintage Tube Radio - Restored & Working Black Dial Zenith Walton 12-s-232Authentic 1936 Antique Zenith Art Deco Farm Radio Model 4v311930`s Zenith 12a57 Console Tube Radio For Parts Or Repair.Zenith Racetrack 5s320 Wood Tube Table Radio - To Repair / Restore - Ca1938 Zenith Radio 10s130 TombstoneVintage Zenith 7s529 3 Band 7 Tube Radio In V. Good Condition, Plays Very Well.1939 Zenith 6d311 Bakelite RadioVintage 1930s Old Zenith Ornate Mantle Style Tube Radio Rare Model With Inlays 1938 Zenith Tombstone Wood Tube Radio Mod. 5-s-228 Short WaveVintage Zenith 6-s-229 Tombstone 6 Tube Radio, Works WellZenith -6-d-219 Black Dial Wood Radio Tube1939 Zenith Bakelite Radio Model 4k310Antique Zenith Vintage Tube Radio 5 R 236 Long Distance Estate Works Gorgeous Restored Mid-century/art Deco Zenith H511 "racetrack" Tube Radio Zenith Radio Bakelite Deco Prewar Original Black Dial M-6d510 Ex Condition WorksZenith 6d525 Am Toaster Model WorkingVintage 1950s Old Classic Zenith & Still Playing Antique Am - Fm Tube RadioAntique Zenith Console Radio 11s474Vintage Zenith Rd-7000y Trans Oceanic 11-band Shortwave Radio Zenith 8-s-434 Model 5810 -- Super Rare Vintage Zenith All Transistor Trans Oceanic Wavemagnet Royal 3000 - 1Vintage Zenith Consol-tone 6d029g Wood Case Table-top Tube Radio / Parts RepairVintage Zenith Tone Register Radio Bakelite As Found!Vintage Zenith 4g903-y Tip-top Holiday 4 Tube Radio, Plays Very WellVintage Zenith Deluxe Clock Radio Tube Life Saver With ManualVintage Zenith Bakelite Model H615 Am Tube Radio-restoredAntique Vintage Zenith Model 1721 Am Fm Bakelite Tube Radio - Early 1950's WorksZenith Trans-oceanic H500 Shortwave All Original Paperwork NiceVintage Zenith J615y Am/sw Long Distance Tube Radio, Plays Very WellMint Antique Vintage Zenith B508w Tube Bakelite Restored Radio Works -see VideoOriginal Atwater Kent & Zenith Radio Service Manual/parts List 1928 - 1931Zenith 6s330Zenith Z615w White Mid 1950s 6 Tube Radio In Working ConditionVintage Tubeless Zenith Red Transistor RadioC 1940 Zenith Model 4f133 Tube Farm Radio-battery OperatedVintage Zenith Portable Radio, WorksOriginal Zenith Wood Knob ?? Black Dial Knob For Shutter-dials (kzw4) ??Zenith Deluxe 5j03 Telechron Antique Tube Clock Radio Owl Eye Bakelite Table Top Zenith Black Dial Wood Tube Radio(2) Zenith 6j5g Triode Tubes Used Test Ok! Clean! Lqqk!! Old Radio AudioVintage Zenith Long Distance Am/fm Tube Radio Model #n731 Ac Power, WorkingZenith G730 Am/fm Table Radio - Collector Grade - WorksAntique Vintage Green Zenith Bakelite Am/fm Tube Radio Model H-723Vintage Zenith Radio1930's Zenith Black Dial Radio Gold Station Indicator & Red Fine Tuning Pointer.Vintage Zenith Deluxe Royal 500 8 Transistor Am Radio W Case Works Made In UsaZenith Nice Shape Table Radio. I Did Hear Static Std And FmVintage Zenith Am Fm Tube Radio Model H725 Needs WorkZenith Radio #k510y-blk Bakelite-1952-just Hums-has Original Owner Instructions!4 Vintage Zenith Dial Station Indicators. Lot #1Rare Pair-zenith Black Dial Radio Wood Tuning Knobs.used On 12a58 And Other SetsVintage Zenith Royal 500 Long Distance 8 Transistor Radio Black & Gold Powers OnVintage Zenith C730 Painted White Wood Am / Fm Table Model Tube Radio - Works!Zenith Black Bakelite Deco Radio Model G510-y Working Vintage Zenith Radio Model X334 Long Distance Tube Radio Am/fm Tabletop Works4 6sl7gt Tubes, Ge, Tungsol, Zenith, + Admiral Hickok Tested Strong TubesZenith Trans-oceanic G500 - Vintage Original Red Ribbon Wavemagnet Cable Zenith 1970's Classic Royal - All Transistor - Radio - Leather Case - Works4 Vintage Zenith Dial Station Indicators. Lot #2