When starting a new electronics project today, one of the first things that we tend to do is pick the integrated circuits that make up the core of the design. This can be anything from a microcontroller and various controller ICs to a sprinkling of MOSFETs, opamps, and possibly some 7400- or 4000-series logic ICs to tie things together. Yet it hasn’t been that long since this level of high integration and miniaturization was firmly in the realm of science-fiction, with even NORBIT modules seeming futuristic.
Starting with the construction of the first point-contact transistor in 1947 and the bipolar junction transistor (BJT) in 1948 at Bell Labs, the electronics world would soon see the beginning of its biggest transformation to that point. Yet due to the interesting geopolitical circumstances of the 20th century, this led to a fascinating situation of parallel development, blatant copying of designs, and one of the most fascinating stories in technology history on both sides of the Iron Curtain. Continue reading “TTL And CMOS Logic ICs: The Building Blocks Of A Revolution”→
In the 1980s, Poland was under the grip of martial law as the Communist government of General Wojciech Jaruzelski attempted to repress the independent Solidarity trade union. In Western Europe our TV screens featured as much coverage of the events as could be gleaned through the Iron Curtain, but Polish state TV remained oblivious and restricted itself to wholesome Communist fare.
In September 1985, TV viewers in the city of Toruń sat down to watch an action adventure film and were treated to an unexpected bonus: the screen had a brief overlay with the messages “Solidarity Toruń: Boycotting the election is our duty,” and “Solidarity Toruń: Enough price hikes, lies, repression”. Sadly for the perpetrators, they were caught by the authorities after their second transmission a few days later when they repeated the performance over the evening news bulletin, and they were jailed for four months.
The transmission had been made by a group of dissident radio astronomers and scientists who had successfully developed a video transmitter that could synchronise itself with the official broadcast to produce an overlay that would be visible on every set within its limited transmission radius. This was a significant achievement using 1980s technology in a state in which electronic components were hard to come by. Our description comes via [Maciej Cegłowski], who was able to track down one of the people involved in building the transmitter and received an in-depth description of it.
The synchronisation came courtesy of the international effort at the time on Very Long Baseline Interferometry, in which multiple radio telescopes across the world are combined to achieve the effect of a single much larger instrument. Before GPS made available a constant timing signal the different groups participating in the experiment had used the sync pulses of TV transmitters to stay in time, establishing a network that spanned the political divide of the Iron Curtain. This expertise allowed them to create their transmitter capable of overlaying the official broadcasts. The police file on the event shows some of their equipment, including a Sinclair ZX Spectrum home computer from the West that was presumably used to generate the graphics.
There is no surviving recording of the overlay transmission, however a reconstruction has been put on YouTube that you can see below the break, complete with very period Communist TV footage.