Cathode ray tubes are wonderful devices, but even today their maintenance demands respect. On one hand, the anode's electrical discharge can kill unsuspecting users, and on the other, the deflection yoke is almost absolutely delicate. In fact, aligning the yoke requires a complex combination of experience, precision, and patience, to the point that some companies developed automatic methods to ensure repeatability and eliminate the human factor from their results. One of those companies was Thomson Consumer Electronics, which prepared this video for its clients at some point in 1995...
One of the first things I was taught about cathode ray tubes was "don't do stupid things with the suction cup." At a bad moment there can be thousands of volts waiting for a discharge path, and no one, no one wants to experience that in person. But there are also other details with the potential to ruin a technician's day... like losing the alignment of the deflection yoke.
While there are many YouTube videos of enthusiasts manipulating the yoke to change image properties, the ideal is to adopt a "do not disturb" philosophy. The manual alignment process consumed time and was not always consistent; however, the people at Thomson Consumer Electronics (whose remnants ended up under Vantiva's wing) presented an automated alignment method, dubbed "yamming":
Yoke alignment with sensors and software, in 1995
The video requires a little patience on our part, due to the mono audio and the buzzing in the right channel. At the same time, it is not a "step-by-step" guide, but a general description. Apparently, the people at Thomson designed a combination of optical sensors and software to extract data that allowed a more precise calibration of the tube-yoke assembly, obtaining results superior to any human eye.
Needless to say, such an advance promised enormous productivity advantages. Although human intervention was always necessary, reducing the multi-phase process of installing a yoke to a thirty-second operation on conventional tubes was still impressive. Thomson also offered solutions for larger tubes, and other customized options for its clients.
Now, all of this made sense in '95, but less than a decade later, Thomson gave the thumbs down to CRT production in the United States, citing "changes" in consumer preferences.
Source: Hackaday
