The Burn-Hole Club

The coils that provide the magnetic force to move the electron beam

Cathode ray tubes are a remarkable technology that incorporate many seemingly magic principles of physics.  Thermionic emission causes electrons to “boil” off a cathode, high voltage electric fields accelerate and focus them, and magnetic fields steer them to the anode screen where they energize phosphor molecules, which then re-release that energy as visible light!

While developing the electronics to control the CRT and make all this magic happen, we often had to “bring up the spot”, showing the electron beam in one static location, where it could be examined visually and measured with various instruments. 

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Behind Gamma’s Disguise

Electron guns from assorted cathode ray tubes.

Those who know me would be stunned to learn that I have a gun collection.  I acquired them in the course of my work trying to make computer images on film in the 1990s.  They are electron guns, the mysterious workings at the business end of a cathode ray tube.

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