2007-03-12 17:39:25 · 2 answers · asked by Rele I 1 in Consumer Electronics ➔ TVs
Hi Fizzle, you must have been to same school as I ! Low emission is caused by gas and impurities leaching out of the electron guns over a few years, then the tube is said to be gassy ! As Fizzle says you can sometimes zap the tube with extra volts, in fact some TV techs carry a machine round on house calls called a CRT rejuvenater , it did similar to zapping !! Cheers Pete
2007-03-14 00:44:23 · answer #1 · answered by Realist 2006 6 · 0⤊ 0⤋
Age, usually. The cathode (gun) back in the neck emits electrons that travel forward and strike the screen in order to make the phosphors glow. Over time there's a crust that builds up on the cathode's emitting surface or it erodes from the constant discharge. An old trick was to zap the gun with a higher than normal voltage in an attempt to blow off the crud and bring up a fresh surface on the cathode, and it did often work. I don't know if ayone actually does that anymore; it does sort of date me to know that. But if it could restore a fresh emitting surface, it would brighten the tube again.
2007-03-13 00:52:16 · answer #2 · answered by Anonymous · 0⤊ 0⤋