Color CRT Monitors

[normicgander 0]

Hey folks- I have two 15" and two 19" color monitors which were installed in July 04. The customer called and said one of the 19" monitors was very dim and was slow to "come on". I swapped at the 19" with a loaner 15" and it was then it was apparent that the remaining three monitors, albeit not as bad, have degraded as well. The OEM tech support said while monitor was in warranty, they have no idea how many hours of life is expected on their monitors. Realizing if the monitors are set to a moderate level of brightness and contrast, what has been some of your experiences with respect to operational life of CRT color video monitors in general?

 

Thanks in advance, Normic

[rory 0]

typically still good even after 5 years ..

 

what was the brand ?

[normicgander 0]

Hey Rory,

 

The monitors are GE Security models MVC-19HR and MVC-15HS. The rep is looking into this matter. I think your numbers are dead-on, but I needed to inquire.

 

The monitors are also cycled down for 5 1/2 hours a day.

 

Thanks much...

[rory 0]

Hmmm .. were they on any type of voltage regulation?

I think the tubes can get damaged from brownouts, spikes, low voltage, etc..

though im not 100% sure on this ..

[normicgander 0]

Until recently the system was on line power. The IT dept installed APC dual conversion UPS units for the entire system.

 

However, appliances/equipment in general, especially TV/mon sets, use switch-mode power supplies which provide regulated DC to the vertical and horizontal circuits. One would think a CCTV grade monitor would employ good power supply circuits, but I could be wrong.

[Cooperman 0]

Nineteen and a bit months of operation in the last two years, and they're a bit poorly; it's not exactly impressive!

 

I have certainly seen operational problems where monitors have been used in a high temperature environment, e.g. stacked monitors, poor ventilation, no air-con etc. which can rapidly degrade components on the PCB's.

 

Most decent monitors have a sub brightness pot on the main circuit board, so whilst a degree of circuit wear can appear to present a significantly reduced brightness adjustment on the front panel, by tweaking up the 'Sub Brightness' you can often recover most if not all of the previous level of Brightness control.

 

It might be worth finding out if they are internally bench adjustable to ofset the wear and tear.

[kandcorp 0]

Most decent monitors have a sub brightness pot on the main circuit board, so whilst a degree of circuit wear can appear to present a significantly reduced brightness adjustment on the front panel, by tweaking up the 'Sub Brightness' you can often recover most if not all of the previous level of Brightness control.

 

I have even seen the sub-brightness control on very cheap B&W 14" and 17" monitors. It would be worth looking into.

[rory 0]

Nineteen and a bit months of operation in the last two years, and they're a bit poorly; it's not exactly impressive!

 

I have certainly seen operational problems where monitors have been used in a high temperature environment, e.g. stacked monitors, poor ventilation, no air-con etc. which can rapidly degrade components on the PCB's.

 

Most decent monitors have a sub brightness pot on the main circuit board, so whilst a degree of circuit wear can appear to present a significantly reduced brightness adjustment on the front panel, by tweaking up the 'Sub Brightness' you can often recover most if not all of the previous level of Brightness control.

 

It might be worth finding out if they are internally bench adjustable to ofset the wear and tear.

 

The Kalatel monitors i've used in the past were some of the best .. just not cheap ... but yes they are adjustable. Hasvent used them since GE took over though ..