Old CRT monitor having no display except single vertical line

Problem in the horizontal deflection circuit, could be as simple as a solder joint, could be more complex, you haven't provided any information that would allow any specific advice though.

Hello, SeventhPrince???! You wrote on 23 Mar 2006 23:19:28 -0800:

S> Hi,

S> Anyone knows of the problem causing old CRT monitor to except single S> vertical line in the middle of the screen?

S> Thanks.

Scan coils around the CRT neck are open circuit, check for dodgy connections in this area..

With best regards, 3T39. E-mail: snipped-for-privacy@hotmail.com

I would check the deflection yoke itself, as the symptoms you mention can be caused by open horizontal deflection coils (the coils themselves are actually open, not just bad connections as the last post suggested). Solid state monitors and TV sets can exhibit this symptom (one bright vertical line) when the horizontal coils are open because SS deflection systems will still allow the HV supply to operate even when the yoke is defective. This is in sharp contrast to tube-powered HV supplies used in older television receivers; if the horizontal yoke coils open in a set of this type, the HV supply will cease to operate.

However, depending entirely upon how old your monitor is, I'd consider getting a new one rather than having the defective one repaired. CRT monitors are almost dirt-cheap these days (I bought my present HP 17" MX-70 monitor for something like $70 after a rebate from Best Buy a couple years ago after its predecessor quit), so I would think at least twice before having your monitor repaired. Just to have someone look at your device in a repair station before repairs are even begun may cost you more than a brand-new monitor. The reason CRT monitors are so inexpensive nowadays is they are being phased out, in favor of flat panels--the same reason CRT-based televisions, large-screen sets and even combis (TV/VCR or TV/VCR/DVD), are so cheap now. I've seen 19" sets going for less than $150 at HHGregg, Best Buy and Circuit City, and smaller sets for well under $100, so really, it is not worth it anymore to have a TV or computer monitor repaired once the manufacturer's one-year (in most cases) warranty expires. It's a sad commentary on life in the USA these days, but we live in a throwaway society in which it is cheaper in almost every case to buy new when something breaks down (after the warranty expires) than to have the old device repaired. Case in point: I have a 19" RCA (Thomson) television I bought new six and a half years ago. It works fine now, has had only one repair (for a minor tuner problem), but if it should develop any kind of problem at this point that puts it entirely out of commission, I will not have it repaired (I had an extended warranty on it which is close to expiring, if it has not expired already). After almost seven years it wouldn't be worth the expense. If the CRT goes (for example), it could cost me $200+ to have it replaced, not including the cost of the service call and other expenses. This is more than I paid originally when I bought the TV in 1999. I can get a new set for a fraction of that amount today, so I'm not even considering having the RCA set repaired when it eventually goes belly up. Twenty-five years ago I'd have had the thing repaired once out of warranty, but not today. The era of replace after the warranty expires is upon us now, unfortunately, no thanks to once-proud USA television manufacturers having shut their US plants down and moved offshore. Zenith, RCA, GE, Magnavox...these are just marketing names (along with their logos) that mean nothing anymore. You buy a Magnavox TV today, for example, and, not surprisingly in this day and age, the chassis is manufactured by Funai or some other offshore company. Zenith was bought out by LG/Goldstar in the late 1980s, RCA/GE was taken over by Thomson about the same time...and on and on the list goes.

Like everything else these days, TV sets are throwaway devices made by no-name offshore companies, no matter the brand name on the cabinet. Zenith once was my favorite brand of home-entertainment equipment, but no more. I wouldn't touch a modern (1990s to now) Zenith-branded TV today with a ten-foot test probe, although I do have a collection of

1950s-1980s Zenith radios built when the company was still an American firm based in Chicago. Even my Zenith 19" color TV in my bedroom was made in Mexico (in the mid-1990s) to the exacting specifications of the former Zenith Radio Corporation; so were my Zenith R-70 AM/FM transistor portable radio and a Zenith AM/FM/FM-stereo clock radio. They work amazingly well for their ages (11 and 25 years respectively). But, I'll say it again, I would not touch, let alone own a Zenith-branded television made in the last decade and a half (except my own set, of course), as these sets are made by offshore companies with no connection whatsoever to the former Zenith Radio Corporation. When they moved offshore, the quality of their products went right down the drain. Even RCA/Thomson has gone well downhill with the rest of them. I have a friend whose parents bought an RCA 25" Guide Plus+ TV in the early 1990s to replace a 15-year-old Zenith System 3 console. The RCA set lasted all of two years, then the CRT blew. They bought a new RCA Guide Plus+ TV which is still working, but the story of how their first one went bad after only two years leaves a bad taste in my mouth as far as RCA quality goes. My own RCA has lasted six and a half years and still has its original CRT (beautiful picture on cable), but I think I was lucky to have gotten a good set, considering all the trouble folks are having with RCA/Thomson televisions these days. As I said, these sets are not worth the cost of even a service call if they go bad after the manufacturer's warranty expires. But (sigh) (oh, nuts!) time only goes forward, and the situation will only get worse and worse before it improves, if it ever does--which I seriously doubt.

(I hereby grant my permission to snip the part of this post having to do with TV quality if any reader so desires; I realize that part of the post could be considered as being controversial or even politically oriented, and, if the truth be known, it had nothing whatsoever to do with my original answer to the question about the vertical white line on a computer monitor screen.)

Jeff, WB8NHV (e-mail addy not shown to deter spammers) Fairport Harbor, Ohio USA

Thanks for the answers. Can't replace with new monitor as this is an old integrated Point of Sales machine somewhat like the Apple CRT monitor I-Mac