Correction on the TV HV circuit; like I said it's been a long time.
The rectifier was a negative half wave (6BK5 as I recall, tall tube with a high voltage cap on it, was in a tin shielded area because it produced X rays due to the high voltage and the rays burned the glass envelope to a brown tint). Reason was that the 26kv was fed to the cathode end of the picture tube. Had to be negative as electrons are what made up the beam and being negatively charged, they traveled to the unlike charge, +.
The control grids (first grid out from the cathode) had the video (BW picture) and were in the -150v give or take and the next grids in line called "screen grids" were the color gun grids were up in the hundreds. Then there was the accelerating anode, part of the gun at the far end (toward the face of the tube) which was at ground potential. So inside the gun (3 guns for a color TV) you launched the electrons via cathode heating (filament power) of the phosphorus coating of the cathode which emitted the electron beam at a - 26kv, pulled forward (accelerated) by the low voltage grids and finally the grounded accelerating anode and by that time they had so much kinetic energy that they kept on going and hit the phosporous coating of the picture tube face and produced luminance.
Color sets had a "shadow mask" that helped the electrons from each colored gun, strike their respective phosphor dot on the rear of the face of the tube. By sending the color information to each grid, you could produce different colors (aka color wheel theory) by varying the voltage on each grid which varied the intensity of each color to obtain the desired hue. Skin tones (hues) were the toughest to get right and hardest for networks to repeat, network to network, program to program in the early days. Forever jumping up and changing the color controls every time a different program came on. Today it's totally academic.
I tell you what's neat. Today's digital TV, No bulky vacuum tube with a long neck protruding out the rear, no high voltage, no weight, no filament heat, NO CONVERGENCE MAGNETS, great cheap price, work forever, everything has a nifty remote control (even air conditioners), integrated entertainment centers are a dream.......wow we live in the right era in history.....the glass is more than half FULL!!!!!!!!
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Today's Featured Article - Listening to Your Tractor - by Curtis Von Fange. Years ago there was a TV show about a talking car. Unless you are from another planet, physically or otherwise, I don’t think our internal combustion buddies will talk and tell us their problems. But, on the other hand, there is a secret language that our mechanical companions readily do speak. It is an interesting form of communication that involves all the senses of the listener. In this series we are going to investigate and learn the basic rudimentary skills of understanding this lingo.
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