# List of experimental television stations

This page is a list of the experimental television stations before 1946. After 1945 (in the United States) the television frequencies were opened up to commercialization and regular broadcasts began. Regular broadcast television start dates vary widely by country; in many regions, initial broadcast video deployment was delayed due to mobilisation for World War II.
(Note: The listing of current broadcast channels for these stations is not up-to-date as many low-VHF stations have moved to UHF frequencies as a result of digital television transition. This is less of an issue in the United Kingdom because of its all-UHF system, but most early US broadcasters were on affected channels before analogue shutdown. Very few full-service North American broadcasters remain on physical channels VHF 2-6 digitally due to impulse noise problems and strict limits on maximum transmitted power at these frequencies.)

## Television stations, as of 1928

Television stations, as of 1928
United States :
| Television call-sign (original) | Television call-sign (current) | City or location | Owner | Transmitter antenna height | Television frequency | Television channel (current) | On air | Off air | Disk holes or lines | Frame rate (frame/s) | Original broadcast system | Current broadcast system |
| WGY | WRGB-TV | Schenectady, New York | General Electric | 380 m | 790 kHz | Channel 6 (VHF) | May 10, 1928 | Present | 48 | Unknown | Mechanical television | ATSC |
| WRNY | None | New York City | Experimenter Publishing | 326 m | 920 kHz | None | August 13, 1928 | 1929 | 48 | 7.5 | Mechanical television | None |
| 2XAL | None | New York City | Experimenter Publishing | (with WRNY), 30.91 | 9.7 MHz | None | August 13, 1928 | 1929 | 48 | 7.5 | Mechanical television | None |
| 3XK | None | Washington, D.C. | Charles Jenkins Laboratories | 46.7 m | 1.605 MHz | None | July 2, 1928 | 1932 (1934?) | 48 | Unknown | Mechanical television | None |
| WOR | WWOR-TV | Secaucus, New Jersey formerly New York City | Bamberger Broadcasting (from WOR) | 405 m | 740 kHz | Channel 9 (VHF) | Unknown | Unknown | Unknown | Unknown | Mechanical television | ATSC |
| KDKA | KDKA-TV | Pittsburgh | Westinghouse Electric Company | 62.5 m | 4.798 MHz | Channel 2 VHF | Unknown | Unknown | Unknown | Unknown | Mechanical television | ATSC |
| 1XAY | None | Lexington, Massachusetts | WLEX | 51–62 m | 1.9 to 4.7 MHz | Unknown | Unknown | Unknown | Unknown | Unknown | Mechanical television | None |
| 4XA | None | Memphis, Tennessee | WSM | 120–125 m | 2.1–2.5 MHz | Unknown | Unknown | Unknown | Unknown | Unknown | Mechanical television | None |
| 9XAA (short-wave station of WCFL, officially W9XAA) | None | Chicago | WCFL/Chicago Federation of Labor | 61.25 m | 4.8 MHz | Unknown | June 19, 1928 | 1937 | 48 | 15 | Mechanical television | None |
| Television stations, as of December 1928 United States ||||||||||||||
| Television call-sign (original) | Television call-sign (current) | City or location | Owner | Transmitter antenna height (m) | Television frequency | Television channel (current) | On air | Off air | Disk holes or lines | frame rate (frame/s) | Original broadcast system | Current broadcast system |
| WGY | WRGB-TV | Schenectady, New York | General Electric | 380 m | 379.5 MHz | Channel 6 (VHF) | 1928 | Still on air | 24 | 21 | Mechanical Television | ATSC |
| 2XAF (Upgrade of WGY) | WRGB-TV | Schenectady, New York | General Electric | 380 m | 31.4 MHz | Channel 6 (VHF) | 1928 | Still on air | 24 | 21 | Mechanical Television | ATSC |
| 2XAD (upgrade of W2XAF above) | WRGB-TV | Schenectady, New York | General Electric | Channel 6 (VHF) | 21.96 MHz | Channel 6 (VHF) | 1928 | Still on air | 24 | 21 | Mechanical Television | ATSC |
| WRNY | None | New York City | Experimenter Publishing | 326 m | 920 kHz | None | August 13, 1928 | 1929 | 48 | 7.5 | Mechanical television | None |
| 2XAL | None | New York City | Experimenter Publishing | (with WRNY), 30.91 | 9.7 MHz | None | August 13, 1928 | 1929 | 48 | 7.5 | Mechanical television | None |
| 3XK | None | Washington, D.C. | Charles Jenkins Laboratories | Unknown | 46.72 MHz | None | July 2, 1928 | 1932 (1934?) | 48 | 15 | Mechanical television | None |
| W9XAA WCFL | None | Chicago | Chicago Federation of Labor | 61.25 m | 61.5 MHz | Unknown | June 19, 1928 | 1937 | 45 | 15 | Mechanical television | None |
| WKBI-TV | None | Chicago | Unknown | ? | 215.7 MHz | ? | ? | ? | 48 | 15 | Mechanical television | None |
| WIBO-lost license May 15, 1933 AKA W9XAO | None | Chicago | Western Television (Sanabria) | ? | 305.9 MHz | ? | Summer 1929 | 1933 | 45 | 15 | Mechanical television | None |
| KGFJ | None | Los Angeles | ? | ? | 212.6 MHz | ? | ? | ? | 48 | -- | Mechanical television | None |
| WLBX | None | Lexington, Massachusetts | ? | ? | 62.5 MHz | ? | ? | ? | 48 | -- | Mechanical television | None |

## Television stations, from 1928 to 1939

Television stations, from 1928 to 1939
United States :
| Television call-sign (original) | Television call-sign (current) | City or location | Owner | Television frequency | Television channel (current) | On air | Off air | Disk holes or lines | frame rate (frame/s) | Original broadcast system | Current broadcast system |
| W9XZV | None | Chicago, IL | Zenith | 2.1-2.2 MHz, later Channel 2 | None | 1939, with a later Zenith experimental station in 1951 | 1953? | ? | ? | Electronic television | None |
| W1WX (later became W1XAV) | None | Boston | SW and Television (Hollis Baird) | 2120 kHz | None | April 1929 (became W1XAV in December 1929) | 1931 | 48 (and later, 60 lines) | 15 | Mechanical Television | None |
| W1XAV | None | Boston | SW and Television (Hollis Baird) | 2.1-2.2 MHz | None | 1930 | 1931 | 48 | 15 | Mechanical television | None |
| W1XAV | None | Boston | Unknown | 2.1-2.2 MHz | SW and Television (Hollis Baird) | 1931 | 1934 | 60 | 20 | Mechanical television | None |
| W1XAY | None | Lexington, Massachusetts | Boston Post, WLEX | 2.0-2.1 MHz | None | 1928 | 1930 | 48 | 18 | Mechanical Television | None |
| W2XB/WGY/W2XAF/W2XAD | WRGB | Schenectady, NY | General Electric | 2.1-2.2 MHz | VHF 6 | 1928 | ? | 48 | 20 | Mechanical television | ATSC |
| W2XCR | None | New York City | Charles Jenkins Laboratories | 2.75-2.85 MHz | None | 1929 | 1931 | 48 | 15 | Mechanical Television | None |
| W2XCR | None | New York City | Charles Jenkins Laboratories | 2.75-2.85 MHz | None | 1931 | 1933 | 60 | 20 | Mechanical Television | None |
| W2XBS | WNBC-TV | New York City | RCA | 2.0-2.1 MHz | Channel 4 (VHF) | 1928 | 1929 | 60? | 20? | Mechanical television | ATSC |
| W2XBS | WNBC-TV | New York City | RCA | 2.75-2.85 MHz | Channel 4 (VHF) | 1928 | 1929 | 60 | 20 | Mechanical television | ATSC |
| W2XAB | WCBS-TV | New York City | CBS | 2.1-2.2 MHz | Channel 2 | 1931 | 1933 | 60 | 20 | Mechanical television | ATSC |
| WRNY | None | New York City | Unknown | 1010 kHz | None | 1928 | 1929 | 36 | ? | Mechanical Television | None |
| WRNY | None | New York City | Unknown | 1010 kHz | None | 1928 | ? | 48 | 10 | Mechanical television | None |
| W2XR | None | Long Island City, New York | Hogan's Radio Pictures | 2.85-2.95 MHz | None | March 26, 1929 | 1934 | 60 | 20 | Mechanical television | None |
| W3XK | None | Wheaton, Maryland (later moved to Silver Spring, Maryland) | Charles Jenkins Laboratories | 6420 kHz (6.42 MHz) | None | 1928 | 1931 | 48 | 15 | Mechanical television | None |
| W3XK | None | Washington, D.C. | Charles Jenkins Laboratories | 2.0-2.1 MHz | None | 1931 | 1934 | 60 | 20 | Mechanical Television | None |
| W9XX, later became W5XA | None | Shreveport, Louisiana | Rev. Lannie W. Stewart | 1604 kHz | None | 1929 | 1934 | 45 | 15 | Mechanical Television | None |
| W5XA | None | Shreveport, Louisiana | Paul L. Carriger | 1594 kHz (video on the 160-meter amateur band) | None | 1932 | 1934 | 45 | 15 | Mechanical television | None |
| W6XAH | None | Bakersfield, California | Pioneer Mercantile Company | 2000–2100 kHz, also simulcast on 1550 kHz in 1932 | None | January 6, 1932 | 1935 | 96 | 20 | Mechanical television | None |
| W9XR | None | Downers Grove, Illinois (Chicago) | Great Lakes Broadcasting/ National Broadcasting Company after 1931. | 2.85-2.95 mHz | None | 1929 | 1933 | 24 | 15 | Mechanical television | None |
| Television stations, from 1928 to 1939 United States and Canada ||||||||||||
| Television call-sign (original) | Television call-sign (current) | City or location | Owner | Television frequency | Television channel (current) | On air | Off air | Disk holes or lines | frame rate (frame/s) | Original broadcast system | Current broadcast system |
| KGFJ | None | Los Angeles | Unknown | ? | ? | 1928 | ? | 48 | ? | Mechanical television | None |
| W3XAD | None | Camden, New Jersey | RCA | 124 MHz to 130 MHz | Channel 5 | July 1930 | Became W3XEP | 525 | 30 | Unknown | None |
| W6XS | None | Los Angeles | Don Lee Broadcasting | 2.1-2.2 MHz | ? | 1931 | 1935 | 80 | 20 | Mechanical Television | None |
| W6XAO | KCBS-TV | Los Angeles | Don Lee Broadcasting | 44.5 MHz (44-50 MHz, Channel 1) | Channel 2 | December 23, 1931 | 1936 | 80 | 20 | Mechanical Television | ATSC |
| W7XAO | None | Portland, Oregon | Wilbur Jerman | 2.75-2.85 MHz | ? | 1929 | ? | Unknown | Unknown | Mechanical Television | None |
| W9XAA, WCFL | None | Chicago | Chicago Federation of Labor | 2.0-2.1 MHz | None | June 19, 1928 | 1937 | 45 | 15 | Mechanical Television | None |
| WIBO-lost license May 15, 1933 AKA W9XAO | None | Chicago, IL | Western Television (Sanabria) | ? | ? | Summer 1929 | 1933 | 45 | 15 | Mechanical Television | None |
| W9XAK | ? | Manhattan, Kansas | Kansas State College | 2.1-2.2 MHz | ? | 1932 | 1939 | 60 | 20 | Mechanical Television | None? |
| W9XAL | Unknown | Kansas City, Missouri | First National Television | 2.1-2.2 MHz | ? | 1933 | 1935 | 45 | 15 | Mechanical Television | None? |
| W9XAO | None | Chicago, IL | Western Television (Sanabria) | 2.0-2.1 MHz | ? | Summer 1929 | 1933 | 45 | 15 | Mechanical Television | None? |
| W9XAP | WMAQ-TV | Chicago, IL | Chicago Daily News/National Broadcasting Company(after 1 November 1931) | 2.1-2.2 MHz | Channel 5 | August 27, 1930 | August 1933 | 45 | 15 | Mechanical Television | ATSC |
| W9XAT | Unknown | Minneapolis, MN | George Young, radio station WDGY | 42-50 MHz, 60-86 MHz (Channel 1) | ? | 1933 | 1938 | 125 | ? | Mechanical Television | None? |
| W9XD | WTMJ-TV | Milwaukee, WI | Milwaukee Journal | ? | ? | 1931 (transmitter used for Apex radio station W9XAZ in 1934) | Experiments ended 1933; License deleted in 1938 | 45 | 15 | Mechanical Television- Western | |
| W9XG | ? | Lafayette, IN | Purdue University | 2.75-2.85 MHz | ? | 1931 | 1939 | 60 | 24 | Mechanical Television | ? |
| W9XK/W9SUI "WSUI", W9XAZ | ? | Iowa City, IA | State University of Iowa | 2.0-2.1 MHz | ? | 1933 | 1939 | 45 | 15 | Mechanical Television | ? |
| W9XUI | ? | Iowa City, IA | State University of Iowa | 2.0-2.1 MHz, later Channel 1, then Channel 2 | ? | 1933 | 1941 | 441 | 30 | Mechanical Television | ? |
| W2XJT | None | Jamaica, New York | Jamaica Radio Television Company | Channel 3, then Channel 13 | None | 1940, moved to Ch. 13 in 1945 | Unknown | ? | ? | Mechanical Television | None |
| VE9EC (also given as VE9AK) | None; TV returned in 1952 with CBFT | Montreal, Quebec | Peck Television Corp. (Canadian Television Ltd.) | 41 MHz | None | 1931 | 1935 | 60-150 | Unknown | Mechanical television | VE9AK's calls were reassigned to CFRB-FM in 1938 |
| Television stations, from 1928 to 1939 Europe ||||||||||||
| Television call-sign (original) | Television call-sign (current) | City or location | Owner | Television frequency | Television channel (current) | On air | Off air | Disk holes or lines | frame rate (frame/s) | Original broadcast system | Current broadcast system |
| Baird Television Ltd. via BBC transmitter 2LO | Unknown | London, England | Baird Television Ltd. | Unknown | ? | September 30, 1929 | June 1932 | 30 | 25 | Mechanical television | PAL/DVB-T? |
| Unknown (Possibly 2LO, as above?) | BBC One | London, England | Baird Television Ltd. | ? | ? | August 22, 1932 | September 11, 1935 | 30 | 25 | Mechanical television | PAL |
| Fernsehsender Paul Nipkow | Unknown | Berlin, Germany | Reichs-Rundfunk-Gesellschaft | ? | ? | 1935 (tests started in 1929) | 1944 | 180/441 beginning in 1937 | 25 | Electronic television | PAL? |
| Doświadczalna Stacja Telewizyjna | TVP 1 | Warsaw, Poland | Polskie Radio Sp. Akc. | ? | | September 1937 (according to other sources regular broadcasts started in 1938) | last week of August 1939 | 120 | 25 | Mechanical television | |

## Television stations, as of 1941

Television stations, as of 1941
United States :
| Television call-sign (original) | Television call-sign (current) | City or location | Owner | Television frequency | Television channel (current) | On air | Off air | Disk holes or lines | frame rate (frame/s) | Original broadcast system | Current broadcast system |
| W1XG | None | Boston | General Television | ? | Channel 1 | Unknown Channel | ? | ? | Unknown | Mechanical television | None |
| W2XVT (Becomes W2XWV in 1944) | WNYW | Passaic, New Jersey | DuMont | Channel 4 | Channel 5 | 1938 | Still on air | 525 | 30 | Mechanical Television | ATSC |
| W2XBS | WNBC-TV | New York City | RCA, NBC | Channel 1 | Channel 4 | 1932 | Still on air | 525 | 30 | Mechanical Television | ATSC |
| W2XAB | WCBS-TV | New York City | CBS | Channel 2 | Channel 2 | 1931 | Still on air | 525 | 30 | Mechanical Television | ATSC |
| W2XWV | WNYW-TV | New York City | DuMont | Channel 4 | Channel 5 | 1938 | Still on air | 525 | 30 | Mechanical Television | ATSC |
| W2XB | WRGB | Schenectady, NY | General Electric | Channel 3 | Channel 6 | 1939 | Still on air | 525 | 30 | Mechanical Television | ATSC |
| W3XWT | WTTG | Washington, D.C. | DuMont | Channel 1 | Channel 5 | 1941 | Still on air | 525 | 30 | Mechanical Television | ATSC |
| W3XNB | WRC-TV | Washington, D.C. | NBC | Channel 2 | Channel 4 | 1939 | Still on air | 525 | 30 | Mechanical Television | ATSC |
| W3XE | KYW-TV | Philadelphia | Philco | Channel 3 | Channel 3 | 1932 | Still on air | 525 | 30 | Mechanical Television | ATSC |
| W3XEP | None | Camden, NJ | RCA | 42 MHz-56 MHz and 50-86 MHz | None | 1931 | 1941? | 525 | 30 | Mechanical television | None |
| W3XPF (Portable unit: W10XX) | None? | Philadelphia | Farnsworth | Channel 3 | Unknown | 1937 | Unknown | 525 | 30 | Mechanical Television | Unknown |
| W3XPP | Cancelled Permit, Now WCAU | Philadelphia | NBC | Channel 7 | Channel 10 | 1939 | Unknown | None | None | Mechanical Television | ATSC |
| W6XAO | KCBS-TV | Los Angeles | Don Lee Broadcasting | Channel 1 | Channel 2 | 1936 | Still on air | 441, changed to 525 in late 1941 | 30 | Mechanical Television | ATSC |
| W6XYZ | KTLA | Los Angeles | Television Productions | Channel 4 | Channel 5 | 1942 | Still on air | 525 | 30 | Mechanical Television | ATSC |
| W6XDL | None | San Francisco, CA | Don Lee Broadcasting | Channel 1 | None | 1941 | Off-Air | 525 | 30 | Mechanical Television | None |
| W8XCT | WLWT-TV | Cincinnati, OH | Crosley Broadcasting | Channel 1 | Channel 5 | 1939 | Still on air | 525 | 30 | Mechanical Television | ATSC |
| W9XV/W9XZV | Became KS2XBS | Chicago, IL | Zenith | Channel 1, then CH 2 | None | 1939–1941, 1951-1953 as KS2XBS | Off-Air | 441, later 525 | 30 | Electronic television | None |
| W9XBK | WBBM-TV | Chicago, IL | Balaban and Katz | Channel 2 | Channel 2 | 1940 | Still on air | 525 | 30 | Mechanical Television | ATSC |
| W9XMJ | | Milwaukee, WI | The Journal Co. | Channel 3 | | 1940 | | 525 | 30 | | |
| WMJT | | Milwaukee, WI | The Journal Co. | Channel 3 | | 1941 | CP returned in 1946 | 525 | 30 | | |

## Television stations, from Jan. 3, 1945 to 1955

Television stations, from Jan. 3, 1945 to 1955
United States :
| Television call-sign (original) | Television call-sign (current) | City or location | Owner | Television frequency | Television channel (current) | On air | Off air | Disk holes or lines | frame rate (frame/s) | Original broadcast system | Current broadcast system |
| W6XAO | KTSL (Now KCBS-TV) | Hollywood, California/Los Angeles, California | Don Lee Broadcasting | Channel 1 | 2.1 (UHF 43) | 1931 | Still on air | 525 | 30 | Mechanical television | Now ATSC |
| W6XHH | None | Los Angeles | Hughes Tool Company | 2 | None | None | None | 525 | 30 | Mechanical television | None |
| W6XZY | KTLA-TV | Los Angeles | Television Productions, Inc. | 4 | 5.1 (UHF 31) | 1942 | Still on air | 525 | 30 | Mechanical television | Now ATSC |
| KSEE | None | Los Angeles | Earl Anthony, Inc. | 6 | None | Unknown | off-air | 525 | 30 | Mechanical television | None |
| W6XHT | None | San Francisco, CA | Hughes Tool Company | 2 | None | Unknown | off-air | 525 | 30 | Mechanical television | None |
| W3XWT | WTTG | Washington, D.C. | DuMont Labs, Inc. | Channel 1 | 5.1 (UHF 36) | 1941 | Still on air | 525 | 30 | Mechanical television | Now ATSC |
| WNBW | WRC-TV | Washington, D.C. | NBC | 2 | 4.1 (UHF 48) | 1941 | Still on air | 525 | 30 | Mechanical television | Now ATSC |
| W9ZV/W9XZV | None | Chicago, IL | Zenith Radio Corp. | Channel 1, then Channel 2 | None | 1939–1941, 1951-1953 as KS2XBS | Off-Air | 525 | 30 | Mechanical Television | None |
| W9XAP | WNBQ-TV 1948-1964 WMAQ-TV 1964- | Chicago, IL | National Broadcasting Company | Channel 5 | 5.1 (UHF 29) | August 27, 1930 | On-Air | 525 | 30 | Mechanical Television | Now ATSC |
| W9XBK | Became W9XCB, then WBKB, now WBBM-TV | Chicago, IL | Balaban and Katz Corp. | Channel 2 | 2.1 (VHF 12) | 1940 | Still on air | 525 | 30 | Mechanical television | Now ATSC |
| W9XCB | WBBM-TV | Chicago, IL | CBS | Channel 4 | 2.1 (VHF 12) | 1940 | Still on air | 525 | 30 | Mechanical television | Now ATSC |
| W9XG | | West Lafayette, IN | Purdue University | 3 | None | 1930 | 1946? | 525 | 30 | Mechanical television | None |
| W9SUI | | Iowa City, IA | University of Iowa | Channel 1, later Channel 12 | None | 1931 | 1941? | 525 | 30 | Mechanical television | None |
| W1XG | | Boston | General Television Corp. | Channel 1 | None | 1931 | 1941? | 525 | 30 | Mechanical television | None |
| W3XEP | None | Camden, New Jersey | RCA | 5, 10, 12 | None | July, 1931 (as portable W3XAD) | 1941? | 525 | 30 | Mechanical television | None |
| W2XVT | WNYW | Passaic, New Jersey | DuMont Laboratories | Channel 4 | 5.1 (UHF 44) | 1938 | Became W2XWV in 1944 | 525 | 30 | Mechanical television | Now ATSC |
| W2XWV | WNYW | Passaic, New Jersey | DuMont Laboratories | Channel 4 | 5.1 (UHF 44) | 1944 | Became WABD-TV in 1944 | 525 | 30 | Mechanical television | Now ATSC |
| W2XJT | None | Jamaica, New York | Jamaica Radio & TV Corp. | Channel 3, then Channel 13 | None | 1940, moved to Ch. 13 in 1945 | 1947? | Unknown | Unknown | Mechanical television | None |
| WNBT | WNBC-TV | New York City | NBC | Channel 1 | 4.1 (UHF 28) | 1928 (as W2XBS) | Still on air | 525 | 30 | Mechanical television | Now ATSC |
| WCBW | WCBS | New York City | CBS | Channel 2 | 2.1 (UHF 33) | 1938 (as W2XAB) | Still on air | 525 | 30 | Mechanical television | Now ATSC |
| WABD | WNYW-TV | New York City | DuMont Labs, Inc. | Channel 4 | 5.1 (UHF 44) | 1938 (as W2XVT, then W2XWV) | Still on air | 525 | 30 | Mechanical television | Now ATSC |
| W2XXB | | New York City | Bamberger Broadcasting Svc. | 6 | | | Experimental | | | | |
| W2XMT | | New York City | Metropolitan Television Inc. | 8 | | | Experimental | | | | |
| WRGB | WRGB-TV | Schenectady, NY | General Electric | 3 | 6.1 (VHF 6) | | Still on-air | 525 | 30 | Mechanical television | Now ATSC |
| W8XCT | | Cincinnati, OH | Crosley Corporation | 1 | | | Experimental | | | |
| W3XE (later WPTZ) | KYW-TV | Philadelphia | Philco Radio & TV | 3 | 3.1 (UHF 26) | Sept 1, 1941 | On-air | 525 | 30 | Mechanical television | Now ATSC, Westinghouse CBS O&O |
| W3XAU | | Philadelphia | WCAU Broadcasting Co. | 5 | | | Experimental | | | | WCAU now operates an ATSC commercial station |
| W8XGZ | | Charleston, WV | Gus Zaharis | 1 | | | Experimental | | | | |
| KS2XBS (First pay-TV service, "PhoneVision") | None | Chicago, IL | Zenith | 2.1-2.2 MHz, later Channel 2 | None | 1951 | 1953? | 525 | 30 | Electronic television | None |
| KC2XAK | None, now part of WNBC-TV | Bridgeport, Connecticut | RCA/NBC | UHF 24 | None | December 29, 1949 | August 23, 1952 | 525 | 30 | NTSC-M | None. Parent station is now ATSC |
| KPTV | KPTV | Portland, Oregon | Empire Coil Company | Channel 27 | 12.1 (VHF 12) | September 20, 1952 | Still on air | 525 | 30 | Used KC2XAK's NTSC-M UHF transmitter, otherwise not experimental. | Now ATSC VHF |
| KE2XDR | | New York City | DuMont Labs | | | 1950 | 1951 | | | Mechanical television | None |
| KPHO | KPHO | Phoenix, Arizona | Gray Television | 5 | 5 | 1949 | | 525 | 30 | | |