Primary color off because open circuit CRT heater

I saw one years ago. I think that some (all?) crt filaments are wired in parallel, and one of them can open causing no color in that gun.

John

Likewise, in 35 years in the business, I can only ever remember one individual heater going open on a TV tube.

Arfa

I have been repairing TV's since 1969 and monitors since 1992. About 2 months ago, I had a Sony 17" monitor with one of the heaters off, resulting in the loss of that color. I think I had one go bad in a TV, but that has been so long ago, that I cannot remember when. John

I have, only on a very few occasions, seen one of the heaters go out in a colour tube. This is very rare. Usually when a CRT goes weak, it is not the heater that is a fault. It is the electron guns that wear out. The CRT heaters will usually work longer than the life span of the set.

--

JANA _____

Somebody says they have had a lot of CRT heaters go open circuit, causing one of the primary colors to go off,

I have been in the trade about 30 years, fixing TV's & computer monitors, I have had a lot of faults were one of the primary color has gone off, But I have never had one of the heaters go off, in fact a work mate joked with me once because we saw this fault-remedy given on Internet. sort of "right !!! pull our other tit"

I have had my share of the heaters going off completely, e.g. all three, but never one or two out of the three.

I would be interested to see what opinions you people have on the CRT heater issue.

I've seen it once on a 70's Sony that had an open red heater. Most CRTs seem to have series connected heaters (at least the ones I've seen with open heaters). I have an 18 month old 27" Panasonic HDTV with open heaters right now. Andy Cuffe

snipped-for-privacy@psu.edu

me

!!!

but

heater

I vaguely recall having a TV pass my way about 25 year back that had an open circuit CRT heater on one colour. I think it was some european thing, like Telefunken or Grundig (it was a long time ago). One of the very few sets I recall that had parallel CRT heaters that came my way.

This is interesting that people are saying that the heaters are in series, normally. I don't think that here in the UK, I have ever seen a tube with anything BUT parallel heaters with a nominal supply voltage of 6.3. That includes both TV sets, domestic, European and Far Eastern, and computer monitors. Is it really common for the three heaters to be in series in the US ? If so, what voltage drives them ? Whose makes of CRT are we talking here ? I would have thought that a lot of CRTs encountered nowadays in the US, would be of far eastern origin, so similar to ones we see over here ??

Arfa

I've seen a couple. At least one was caused by a bad weld on the connecting "wires" in the neck.