You’ve heard of Bell Labs, but likely you can’t go far beyond naming the most well-known of discoveries from the Lab: the invention of the transistor. It’s a remarkable accomplishment of technological research, the electronic switch on which all of our modern digital society has been built. But the Bell Labs story goes so far beyond that singular discovery. In fact, the development of the transistor is a microcosm of the Labs themselves.
The pursuit of pure science laid the foundation for great discovery. Yes, the transistor was conceived, prototyped, proven, and then reliably manufactured at the Labs. But the framework that made this possible was the material researchers and prototyping ninjas who bridged the gap between the theory and the physical. The technology was built on what is now a common material; semiconducting substances which would not have been possible without the Labs refinement of the process for developing perfectly pure substances reliably doped to produce the n-type and p-type substances that made diode and transistor possible.
If we cast our minds back to the early years of the transistor, the year that is always quoted is 1947, during which a Bell Labs team developed the first practical germanium point-contact transistor. They would go on to be granted the Nobel Prize for their work in 1956, but the universal adoption of their invention was not an instantaneous process. Instead there would be a gradual change from vacuum to solid state that would span the 1950s and the 1960s, and even in the 1970s you might still have found mainstream devices on sale containing vacuum tubes.
To speed up this process, Bell Labs made every effort to publicize their invention. Thus we come to our subject today, their 1953 publicity film The Transistor, in which the electronics industry of the era is described and how each part of it might revolutionize by the transistor is laid out.
We start with a look at a selection of electronic components, among which are a few transistors. The point contact device is already described as superceded by the junction transistor, but as well as those two we are shown a phototransistor and a junction tetrode, a now-obsolete design that had two base connections.
Unexpectedly we don’t dive straight into the world of transistors, but take a look back at the earlier years of the century to the development of vacuum electronics. We’re taken through the early development and operation of vacuum tubes, then their use in long-distance radio communications, through the advent of electronics in mass entertainment, and finally into the world of radar and microwave links. Only then do we return to the transistor, with a posed shot of [John Bardeen], [William Shockley], and [Walter Brattain] hard at work in a lab. The merits of the transistor as opposed to the tube are then set out, though we can’t help wondering whether they have confused a milliwatt and a microwatt when they describe the transistor as requiring only a millionth of a watt to operate.
They just don’t write promotional film scripts like they used to: “These men are design engineers. They are about to engage a new breed of computer, called Graphic 1, in a dialogue that will test the ingenuity of both men and machine.”
This video (embedded below) from Bell Labs in 1968 demonstrates the state of the art in “computer graphics” as the narrator calls it, with obvious quotation marks in his inflection. The movie ranges from circuit layout, to animations, to voice synthesis, hitting the high points of the technology at the time. The soundtrack, produced on their computers, naturally, is pure Jetsons.
This gem from the AT&T Archive does a good job of explaining the first-generation cellular technology that AT&T called Advanced Mobile Phone Service (AMPS). The hexagon-cellular network design was first conceived at Bell Labs in 1947. After a couple of decades spent pestering the FCC, AT&T was awarded the 850MHz band in the late 1970s. It was this decision coupled with the decades worth of Bell System technical improvements that gave cellular technology the bandwidth and power to really come into its own.
AT&T’s primary goals for the AMPS network were threefold: to provide more service to more people, to improve service quality, and to lower the cost to subscribers. Early mobile network design gave us the Mobile Service Area, or MSA. Each high-elevation transmitter could serve a 20-mile radius of subscribers, a range which constituted one MSA. In the mid-1940s, only 21 channels could be used in the 35MHz and 150MHz band allocations. The 450MHz band was introduced in 1952, provided another 12 channels.
The FCC’s allocation opened a whopping 666 channels in the neighborhood of 850MHz. Bell Labs’ hexagonal innovation sub-divided the MSAs into cells, each with a radius of up to ten miles.
The film explains quite well that in this arrangement, each cell set of seven can utilize all 666 channels. Cells adjacent to each other in the set must use different channels, but any cell at least 100 miles away can use the same channels. Furthermore, cells can be subdivided or split. Duplicate frequencies are dealt with through the FM capture effect in which the weaker signal is suppressed.
Those Bell System technical improvements facilitated the electronic switching that takes place between the Mobile Telephone Switching Office (MTSO) and the POTS landline network. They also realized the automatic control features required of the AMPS project, such as vehicle location and automatic channel assignment. The film concludes its lecture with step-by-step explanations of inbound and outbound call setup where a mobile device is concerned.
This is the under-the-hood view of the keyboard for the Voder (Voice Operating Demonstrator), the first electronic device capable of generating continuous human speech. It accomplishes this feat through a series of keys that generate the syllables, plosives, and affricatives normally produced by the human larynx and shaped by the throat and tongue. This week’s film is a picture montage paired with the audio from the demonstration of the Voder at the 1939 World’s Fair.
The Voder was created by one [Homer Dudley] at Bell Laboratories. He did so in conjunction with the Vocoder, which analyzes human-generated speech for encrypted transfer and re-synthesizes it on the other end. [Dudley] spent over 40 years researching speech at Bell Laboratories. His development of both the Voder and the Vocoder were instrumental in the SIGSALY project which aimed to deliver encrypted voice communication to the theatres of WWII.
At the Vintage Computer Festival last weekend, there was a wonderful representation of small 8 and 16-bit home computers from the 80s, an awful lot of PDP and VAX-based minicomputers, and even some very big iron in the form of a UNIVAC and a Cray. You might think this is a good representation of computing history, but there was actually a huge gap in the historical reality. Namely, workstations and minicomputers that weren’t made by DEC.
[Ian Primus] was one of the very few people to recognize this shortcoming and brought his PRIME minicomputer. This was a huge, “two half racks, side by side” computer running PRIMOS, an operating system written in FORTRAN. Of course this made it extremely popular with engineering teams, but that doesn’t mean [Ian] can’t have fun with it. He had two terminals set up, one running Dungeon (i.e. Zork pre-Infocom) and a text-based lunar lander game.
Because the VCF East is held in New Jersey, it’s probably no surprise a few vintage AT&T Unix boxes showed up. [Anthony Stramaglia] brought in a few very cool vintage Unix workstations, dating from the early to mid 80s. In the video, he shows off two AT&T boxes. The first is a UNIX PC, containing a 68010 clocked at a blistering 10 MHz. Next up is the UNIX PC’s bigger brother, the 3B2 400. This is the workstation found on just about every desk at Bell Labs in the 80s, meaning this is the same computer [Ken Thompson] and [Dennis Ritchie] used for their work on UNIX.
Few births are easy. Even fewer result in a Nobel Prize, and hardly any at all are the work of three men. This 1965 film from the AT&T archives is a retrospection on the birth of the transistor nine years after its creators, [Walter Brattain], [John Bardeen], and [William Shockley] received a Nobel Prize in Physics for their discovery and implementation of the transistor effect.
The transistor is the result of the study of semiconductors such as germanium. Prior to the research that led directly to the transistor, it was known that the conductivity of semiconductors increases when their temperature is raised. The converse is true for metals such as tungsten. Semiconductor conductivity also increases when they are exposed to light. Another key to their discovery is that when a metal such as copper is in contact with a semiconductor, conductivity is less in one direction than the other. This particular property was exploited in early radio technology as seen in crystal radios, for copper oxide rectifiers used in telephony, and for microwave radar in WWII.
After WWII, AT&T’s Bell Labs put a lot of time and research into the study of semiconductors, as their properties weren’t fully understood. Researchers focused on the simplest semiconductors, silicon and germanium, and did so in two areas: bulk properties and surface properties. During this time, [Shockley] proposed the field effect, supposing that the electrons near the surface of a semiconductor could be controlled under the influence of an external electric field.