AT&T Archives: Advanced Mobile Phone Service (AMPS), a 1978 film on cell phones

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Using simple graphics, this film, made in 1978, illustrates the concept of cellular telephony in easily-understood terms, which are instructive even today, since the basic idea of dividing a service area into a pattern of small cells remains the same.

As the film points out, the concept of using these small cells was developed at Bell Labs, and it was this idea that constituted the giant leap from earlier, less efficient mobile phone systems to today’s modern cell service. What the film does not mention: the year the cellular idea was first proposed at the Labs, which was 1947.

In 1946, AT&T had introduced the first commercial mobile telephone service in St. Louis, Missouri. The equipment weighed nearly 80 pounds and was installed in a subscriber’s motor vehicle. A single transmitter on a central tower provided service to the entire area, and only a handful of channels had to be shared by all subscribers. Before long, more channels were needed for mobile service to continue to grow. That’s when Bell Labs engineer, D.H. Ring, proposed a solution.

In his 1947 memorandum, Ring outlined a hexagonal grid system composed of multiple low-power transmitters with automatic call handoff from one hexagon to another. The scheme would enable reuse of frequencies within a given area, dramatically increasing the mobile network’s capacity. But at the time, the technology to implement Ring’s proposal did not yet exist, and it would be another few decades before this scheme would be revisited by AT&T Bell Labs engineers Richard Frenkiel and Joel Engel. Their work would provide the basis for an AT&T proposal in 1971 to the Federal Communications Commission (FCC) for a cellular network. The FCC would later grant AT&T permission in 1977 to start conducting trials of a cellular system in the United States. The first commercial cellular system in the U.S., in Chicago, followed in 1983.

Footage Courtesy of AT&T Archives and History Center, Warren, NJ

50 Comments

  1. axel flores on March 24, 2021 at 10:38 pm
  2. Carlos Pulpo on March 24, 2021 at 10:40 pm

    Wow this brings back memories of the real phone hacking before rooting and jail-breaking became a thing. I had a old Motorola "bag" phone that was totally modified via hardware and change of EPROM code so I could do almost anything I wanted on a network, basically without going in to great detail I had low level control over all the transceiver and data operations on the phone, use your imagination! . I made a serial connection to a PC and wrote the accompanying software to control it. I gave the phone the nickname "superphone" and the good times with that.

  3. Billy Fowler on March 24, 2021 at 10:40 pm

    Tropospheric ducting most common late at night during areas of high pressure still caused issues with amps along with intermodulation (crosstalk), but it wasn’t as big of an issue as with the older systems on the lower frequencies.

  4. Tuomas Levoniemi on March 24, 2021 at 10:41 pm

    Interesting information about AMPS. However, it can be said AMPS was technically pretty old-fashioned when it was released. Compared to NMT (=Nordic Mobile Telephone / 1G) by Nokia and Ericcson.
    Also, ARP (Autoradiopuhelin, "car radio phone") had been widely used in Finland in the from the start of 1970.

  5. mystica5551212-subs on March 24, 2021 at 10:42 pm

    I love how they call "small cells" something starting out at 4-mile radius (before going maybe down to 1 mile)! That term has changed so much in ~40 years. In a city, 1 mile is often way too large for a single cell. Suburbia loves 1 mile cell radii however, much to the chagrin (and slow datarates) of the hundreds of customers within each sector…

  6. im lost on March 24, 2021 at 10:43 pm

    1G

  7. SteelRodent on March 24, 2021 at 10:44 pm

    just a completely unrelated fact: in Scandinavia we had NMT, which as I understand it worked on the same principle as AMPS, and it was terrible. Poor range, even worse audio quality, and despite the early phones running off motorcycle batteries, the actual battery life was a few hours at best. It was however the only cellphone system we had until GSM came around in the early 1990s, but NMT still stuck around for another decade – especially because the train and bus communication system used it. Then they suddenly decided to shut it down and the railroad was forced to refit all their trains to use a GSM based system

  8. John B on March 24, 2021 at 10:44 pm

    Music used: ‘Flying High’ by James Clarke, from the album ‘Music Pictorial’ KPM 1972.

  9. Nate Newman on March 24, 2021 at 10:44 pm

    Now everyone has a cellphone. More common that’s their primary phone.

  10. Christopher on March 24, 2021 at 10:46 pm

    All this technology now and you still a can’t get a cell phone call to sound as good as a landline

  11. Marc Field on March 24, 2021 at 10:46 pm

    The very basis of how cell, and smart phones work today. Very fascinating indeed. Besides how else could we text and drive?

  12. Chris Cross on March 24, 2021 at 10:46 pm

    Well in 1978 in Europe hate was born

  13. steadfastcoward on March 24, 2021 at 10:47 pm

    You may not realize that the growing need for both cellular and emergeny communications will turn your television service on it’s head in the next two years, as the FCC ‘repacks’ the band and eliminates most channel about channel 38. In addition to any new stations seeking to air, existing stations will be moved and eve combined (piggybacked) with other program services/licensees as well. Your antenna TV is about to get crazy.

  14. George Kassimis on March 24, 2021 at 10:48 pm

    Hm. This 5G thing is more confusing than I thought.

  15. John Siders on March 24, 2021 at 10:48 pm

    I got my first cell phone in 1984 they were called car phones had that big box in the back of the truck behind the seat on the cab back wall had the handset on the dash with the keypad and mic speaker a heavy coiled cord to the cradle that held it was a Motorola full 4 watt system the antenna took a 3/4 inch hole in the roofs center and it cost like almost 4 K ! For the system and installation I was working for the wild well people and it demanded instant finding of us when a call came in of a blowing or burning oil or gas well it was a dollar a minute to use and out side your home area it had a roaming charge of 3 dollars per day on top of the air time and if you traveled out of that area you got hit with roaming again ! Of course before all we had were these big pagers that only beeped no texting or voice if it went off you called the office out in public people would stare at you like you were some kind of big shot to have a pager and using the car phone going down the road other cars people pointed at you like wow that’s a rich man he’s got a phone ! LOL we were just oil field trash . Doing a important job .

  16. IstvanN1961 on March 24, 2021 at 10:50 pm

    We lost a great resource when we lost Bell Telephone Laboratories and Western Electric. May "Judge" Harold Green rot in eternal hell.

  17. Will It Fizz! on March 24, 2021 at 10:52 pm

    I’d think this would be a magnet for car thief’s back then

  18. Oliver White on March 24, 2021 at 10:55 pm

    666 Channels

  19. Jamie Woods on March 24, 2021 at 10:55 pm

    The "recently allocated frequency frequency band" (13:38) was actually UHF TV channels 70 through 83. Until about 1984/85 most TVs were sold with UHF tuners going up to channel 83. However, channels 70-plus were never actually used by the FCC for commercial or educational TV.

  20. Michael Livingstone on March 24, 2021 at 10:56 pm

    They still use AMPS in Saskatchewan due to the sparsely populated rural nature of the province.

  21. Hopi Ng on March 24, 2021 at 10:58 pm

    3:47

  22. PR Fo on March 24, 2021 at 10:59 pm

    Oddly, despite being obsolete I occasionally still see payphones/phone booths in some rest areas.

  23. The Readers Corner on March 24, 2021 at 11:00 pm

    5:31 the DEVIL >:D

  24. hansonsux on March 24, 2021 at 11:02 pm

    666 lol

  25. Jj Fatts on March 24, 2021 at 11:03 pm

    666 channels, ‘eh? Sounds like AMPS was the 5G of decades past.

  26. Quaalude Charlie on March 24, 2021 at 11:05 pm

    This makes me Happy 🙂 QC

  27. Luis de Santos on March 24, 2021 at 11:08 pm

    This describes the precursor to what we call a cellular network, and really has nothing in common with it.

  28. The Lavian on March 24, 2021 at 11:09 pm

    These days you can get arrested for using your phone while driving.

  29. Ronald McDonald on March 24, 2021 at 11:10 pm

    The first mobile phone, as in a hand set was in 1978. It was gigantic. I want to use one, just to see how it works.

  30. Christina Douglas on March 24, 2021 at 11:10 pm

    I always wondered why they call them "cell" phones. Now I know why

  31. MK Barton on March 24, 2021 at 11:11 pm

    And this is why money never sleeps, pal!

  32. John Opalko on March 24, 2021 at 11:11 pm

    I worked on the AMPS project when I was at Bell Labs. Wow, that was a fun job! I guess I’m just an old softie, but this video brought tears to my eyes. I left the Labs shortly after Divestiture and went on to work for McCaw Cellular. That was fun, too, and it got me to Seattle. No more Chicago winters!

  33. D on March 24, 2021 at 11:15 pm

    What hath god wrought?!

  34. johneygd on March 24, 2021 at 11:17 pm

    So in the late 1930’s the first mobile push to talk handset was developed for use in cars,whooaah, those peoples in the 30’s who dit had one were 70+ years ahead of it’s time as we consummers were able to talk with eachother mobile in the car became common in the late 90’s early 2000.
    HOWEVER, what creeps me out is that those scientists from at&t decided to devide the 850 frequency into the number of the beast.

  35. JJ Vernig on March 24, 2021 at 11:17 pm

    Why does the car from 8:00 onwards look like the flintstones?

  36. Richard Fallstich on March 24, 2021 at 11:18 pm

    I started working at Western Electric in 1978, the year this film was made.  The Bell System was behind some of the most advanced technologies, well before other companies.

  37. Hot80s on March 24, 2021 at 11:23 pm

    0:15 Cougar with a Cougar

  38. Mark Arca on March 24, 2021 at 11:25 pm

    AMPS is deprecated in the late 90s to early 2000s and replaced by GSM (1G).

  39. Randy Maatta on March 24, 2021 at 11:25 pm

    AT 3:50 mark. 666 channels. We really were asleep back then.

  40. Darth Rageous on March 24, 2021 at 11:27 pm

    INTERESTING. v-e-r-y interesting indeed!

  41. xaenon on March 24, 2021 at 11:27 pm

    Ha!  An AMC Pacer!   Just when I though I’d forgotten those things!

  42. Nate Newman on March 24, 2021 at 11:27 pm

    I used CDMA AMPS on phones I had between 2001-2004(?). Whenever the Analog network was shut down.

  43. Michael O'Neill on March 24, 2021 at 11:28 pm

    Where is the gd side view mirror on the vehicle at the end? They’re on a highway ffs!

  44. A THEORY GONE CRITICAL on March 24, 2021 at 11:29 pm

    This had to be made by a Zionist, 33,666, the 6 point honeycomb =star of david,

  45. Jamie Woods on March 24, 2021 at 11:31 pm

    Hand off — when your call drops. While this still occurs, it’s getting less frequent. I’ve been using cell phones since late 1998. Remember the days of Roaming charges?

  46. Jason Reed on March 24, 2021 at 11:34 pm

    13:29 How funny! The lady almost cuts off the car coming up behind her. Don’t forget to check your blind spot! lol Then the passenger picks up the phone… Love it!

  47. PR Fo on March 24, 2021 at 11:35 pm

    i just realized that on top of the fact that AMPS is divided into 666 channels, its logo is made up of hexagons. As most people know a hexagon is a six sided figure. The logo has six hexagons surrounding the center hexagon. The six exterior hexagons are in two alternating colors. This means there are three exterior hexagons in each color or 6-6-6.

  48. Graham Crichton on March 24, 2021 at 11:35 pm

    8:57 Get out! It’s going to blow!

  49. OALM on March 24, 2021 at 11:36 pm

    So that’s why they’re called cell phones!!!

  50. Syl damours on March 24, 2021 at 11:37 pm

    je veux retirer att de mon cellulaire je ses que je peut appeller demain matin mes je me demande si je peux pas y arriver ce soir

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