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Old 10-22-2007, 04:01 AM
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Kiwick Kiwick is offline
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Join Date: Mar 2007
Location: Italy
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Some early 70s 110-degree In-line CRTs like Toshibas, the GTE-Sylvania Uniline, and the Philips 20AX weren't self converging, they still had convergence coils on their necks and required a convergence circuit with lots of adjustment knobs just like delta gun CRTs...

Self converging "Precision in line" tubes (RCA) which were the first to do away with any kind of convergence circuit in the mid-late 70s, had a finer stripe pitch in the center of the screen, and a quite coarse pitch at the sides, unlike earlier inline CRTs which had a constant stripe pitch all over their screen

as for bulb strenght, the real challenge was posed by early 110-degree B/W CRTs, as the flatter bell and increased vacuum would put a lot of strain on the edge of the screen, so early 110-deg tubes were very fragile and dangerous, but by the time the first 110-degree color CRTs came out in the late 60s, the "tensioned rimband" integral implosion protection had already been invented.

In fact, a good CRT (both 90 or 110 degree) with a serious tensioned rimband is extremely safe, and does away with the need for bonded lenses or separate safety glasses... actually, you can't get one to implode even if you smash it with a hammer... it will just break where you hit it and quietly lose the vacuum through the hole.
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