LCD Monitor?

Chuck · Post by **Chuck** » Sun Feb 17, 2008 3:24 pm

Don and I were talking today and he brought up the possibility of replacing the crt (when it dies) with a lcd monitor. With the contrast ratio of a lcd that would probably be very cool. I'll have to try it!

digger47 · Post by **digger47** » Mon Feb 18, 2008 8:35 am

I have often thought about this and wondered why it hasen't been done.
my display will have to be replaced someday soon and I'm interested.
keep us posted.

Kenbo · Post by **Kenbo** » Mon Feb 18, 2008 7:49 pm

I'd sure like to see what p2k would look like with an LCD monitor. Less heat, better contrast, higher reliability, it seems like it would be a winner.

ChadTower · Post by **ChadTower** » Wed Feb 20, 2008 4:29 pm

I would be concerned with the way an LCD would project off of the playfield glass - if it does at all. LCDs aren't the same type of projected light source that a CRT is. It may work, but not quite the same way as a CRT, such that you'd have to alter the way it is mounted in relation to the surface it is projecting onto.

LCDs have inferior contrast to CRTs and there is just no proof of them being more reliable. CRTs run for thousands of hours before they break down - in home use this is practically indefinite for a game. They are far less repairable than CRTs unless you have some high end SMD soldering skills.

Chuck · Post by **Chuck** » Fri Feb 22, 2008 1:51 am

ChadTower wrote:I would be concerned with the way an LCD would project off of the playfield glass - if it does at all. LCDs aren't the same type of projected light source that a CRT is. It may work, but not quite the same way as a CRT, such that you'd have to alter the way it is mounted in relation to the surface it is projecting onto.

LCDs have inferior contrast to CRTs and there is just no proof of them being more reliable. CRTs run for thousands of hours before they break down - in home use this is practically indefinite for a game. They are far less repairable than CRTs unless you have some high end SMD soldering skills.

I think the interesting point of using an lcd is the superior contrast ratio to the standard pb2k monitor. I've seem too many people driving their monitors so hard that you get a gray haze that covers up parts of the playfield that should not be covered. I think a lcd will be bright enough but I'll have to test it to tell. I'm only suggesting this for people who might have to replace the original monitor. Then again, it might look much better so it may be an enhancement mod

I may do a test this weekend just for grins.

ChadTower · Post by **ChadTower** » Fri Feb 22, 2008 11:01 am

Hrm. I'm not familiar with the specific model in P2K. Is that running at 15khz or something higher?

Is it a flatscreen or a traditional CRT face? There could be angle of projection issues going from a rounded face to a flat LCD. It would probably be correctable but that may make this a little less of drop in replacement.

JMX · Post by **JMX** » Fri Feb 22, 2008 11:53 am

Im curious what your findings will be chuck. The brightness could be a issue, but i think the geometry issue would be easily corrected in software with a filter if its noticable.

Even if a arcade monitor and a lcd monitor dont differ in price so much, a lcd is easier to obtain.

This topic has also been discussed on rgp:
http://groups.google.com/group/rec.game ... 2532d169e2

And on contrast issues on pin2000:
http://groups.google.com/group/rec.game ... 76e149e7a6
http://groups.google.com/group/rec.game ... da2d76e854

ChadTower · Post by **ChadTower** » Fri Feb 22, 2008 2:16 pm

JMX wrote: This topic has also been discussed on rgp:
http://groups.google.com/group/rec.game ... 2532d169e2

Heh. Note that one of the people in that discussion is me.

Chuck · Post by **Chuck** » Fri Feb 22, 2008 2:24 pm

ChadTower wrote:Hrm. I'm not familiar with the specific model in P2K. Is that running at 15khz or something higher?

Is it a flatscreen or a traditional CRT face? There could be angle of projection issues going from a rounded face to a flat LCD. It would probably be correctable but that may make this a little less of drop in replacement.

15.7k cga crt. It is convex like any other old monitor.

Kenbo · Post by **Kenbo** » Fri Feb 22, 2008 7:24 pm

I still contend that the LCD display will improve reliability. Even if the LCD itself is less reliable than a standard monitor (not sure about that) the huge reduction in heat surely would reduce collateral heat damage to other components.

Chuck · Post by **Chuck** » Fri Feb 22, 2008 7:26 pm

I looked all over today for lumen specs on crts and lcd. I couldn't find specs anywhere. They rate lcd's in cd/m2 (which I'm guessing is candelas per meter squared) I couldn't find any specs for old crts.

Chuck · Post by **Chuck** » Fri Feb 22, 2008 7:29 pm

yeah, it figures that once I post something saying I can't find data, I find data. An average lcd is 500 cd/m2. I found specs on a sony trinitron studio monitor and it was 100 cd/m2. So lcd's might actually be brighter than the original crt and with the higher contrast ratio may make the video look even better.

*maybe*

Chuck · Post by **Chuck** » Sun Feb 24, 2008 3:37 pm

ok, WOW...

The brightness and color quality of my 19" junk lcd I'm using for testing was pretty incredible off the mirrored glass. So this definately can be done and after all the smoke clears I WILL be doing it

There is only one real issue. A 19" lcd isn't wide enough to extend the picture like the original monitor. I'm sure a 20" or 21" would work fine.

digger47 · Post by **digger47** » Sun Feb 24, 2008 10:06 pm

great news, my monitor is on its last leg.

ChadTower · Post by **ChadTower** » Tue Feb 26, 2008 3:38 pm

Chuck wrote:ok, WOW...

The brightness and color quality of my 19" junk lcd I'm using for testing was pretty incredible off the mirrored glass. So this definately can be done and after all the smoke clears I WILL be doing it

There is only one real issue. A 19" lcd isn't wide enough to extend the picture like the original monitor. I'm sure a 20" or 21" would work fine.

Is it projecting close enough to the original playfield spots? The curve of the CRT screen has different projection angles than a flat LCD.