PDA

View Full Version : EGA/CGA Monitor Troubleshooting/Solutions.



november
November 21st, 2008, 05:04 AM
Hi,

I have a client in Chicago who needs 6 to 10 monitors repaired or replaced.

Did some digging and found out that these are either EGA/CGA (not sure how to tell yet as I haven't seen the hardware).

I'd like to know if anyone knows of any resources for repair or replacements.

I was thinking of, if possible, a normal monitor with a CGA/EGA to VGA adapter and backup battery.

I'm thinkin the UPS will protect from the dirty electricity of the factory and the adapter will allow the use of much cheaper monitors to display the necessary text.

Please help with ANY information that you can.

Thank you in advance.

Chuck(G)
November 21st, 2008, 07:21 AM
A scan converter might work okay. There are prints and manuals on various pay-for-subscription sites for some of the more common monitors.

The big issue will be cost-effectiveness (I assume you charge for your field and bench time). Replacement parts may be something else to consider.

I don't know what kind of systems these are or their dependency on specific hardware, but I wonder if you could find a quantity of ISA VGA cards (or even better, PCI if these systems are of an appropriate vintage) and simply replace all of the monitors with modern ones. VGA and EGA cards do share a lot of commonality in the software interface--it might be close enough.

Just tossing some thoughts out there.

november
November 21st, 2008, 07:27 AM
A scan converter might work okay. There are prints and manuals on various pay-for-subscription sites for some of the more common monitors.

The big issue will be cost-effectiveness (I assume you charge for your field and bench time). Replacement parts may be something else to consider.

I don't know what kind of systems these are or their dependency on specific hardware, but I wonder if you could find a quantity of ISA VGA cards (or even better, PCI if these systems are of an appropriate vintage) and simply replace all of the monitors with modern ones. VGA and EGA cards do share a lot of commonality in the software interface--it might be close enough.

Just tossing some thoughts out there.

That's not a bad idea.

I'm not sure if I'll be able to plug and play with a new card.

From what I'm told these are machines that display their totals and at the end of the day they manually write down the totals and input them for records purposes.

Also, they don't have any hard discs, all memory is on the boards in the system. So I don't know/think it may be an option.

I'll have to wait for the report form my co-worker....or go there myself to see what's what.

Thank you for your quick reply. I love having more options to choose from.

Chuck(G)
November 21st, 2008, 08:56 AM
One possible fly in the ointment is that EGA horizontal frequency is about 21.8 KHz, as opposed to 15.75 KHz for CGA--I don't know if commercially available scan converters will handle it, so some research might be in order if you decide to go that route.

There are OEM-style (i.e. open frame) LCD monitors made that will handle CGA/EGA/XGA/VGA scan rates:

Starlite Gaming has some, for example (http://www.starlitegaming.com/Monitors_and_LCDs.html)

barythrin
November 21st, 2008, 09:15 AM
I agree and I know it may be a stretch, but I'd try a VGA card in one of the systems first, then maybe you can just get some regular monitors hooked into the system.

Depending on the monitor and problem/symptom some can be fixed if it's just a scan frequency issue. A lot of monitors inside *note: don't dig around in one unless you're familiar with the risks of flyback transformers and/or TV repair* have a potentiometer that you can adjust with a screwdriver and fix some simple issues.

I suppose you might check some auction sites for parts if you're looking around for monitors but I'm not sure the success rate of one working well or finding several of the same ones would be.

november
November 21st, 2008, 10:07 AM
One possible fly in the ointment is that EGA horizontal frequency is about 21.8 KHz, as opposed to 15.75 KHz for CGA--I don't know if commercially available scan converters will handle it, so some research might be in order if you decide to go that route.

There are OEM-style (i.e. open frame) LCD monitors made that will handle CGA/EGA/XGA/VGA scan rates:

Starlite Gaming has some, for example (http://www.starlitegaming.com/Monitors_and_LCDs.html)

That may be an option but there is no frame :-/. I'll look into it.

I'm still not sure if it's which platform it is yet, I'm sure the video card will help me determine that.


I agree and I know it may be a stretch, but I'd try a VGA card in one of the systems first, then maybe you can just get some regular monitors hooked into the system.

Depending on the monitor and problem/symptom some can be fixed if it's just a scan frequency issue. A lot of monitors inside *note: don't dig around in one unless you're familiar with the risks of flyback transformers and/or TV repair* have a potentiometer that you can adjust with a screwdriver and fix some simple issues.

I suppose you might check some auction sites for parts if you're looking around for monitors but I'm not sure the success rate of one working well or finding several of the same ones would be.

I haven't seen the monitors that need to be fixed.

I will be seeing 1 this weekend.

I'd really like to be able to get this taken care of this without having to go all the way to Chicago (about an hour drive for me) just to assess the situation. I do assume I'll have to do that as my co-worker is new to the IT field in general.

Bah, anyhow, I will come back when I have some more information.

Also, will I run into frequency issues if I convert from EGA or CGA to VGA?

I assume so, because the monitors will need to be able to handle the proper frequency.

More research is definitely necessary.

Druid6900
November 21st, 2008, 12:51 PM
That may be an option but there is no frame :-/. I'll look into it.

I'm still not sure if it's which platform it is yet, I'm sure the video card will help me determine that.



I haven't seen the monitors that need to be fixed.

I will be seeing 1 this weekend.

I'd really like to be able to get this taken care of this without having to go all the way to Chicago (about an hour drive for me) just to assess the situation. I do assume I'll have to do that as my co-worker is new to the IT field in general.

Bah, anyhow, I will come back when I have some more information.

Also, will I run into frequency issues if I convert from EGA or CGA to VGA?

I assume so, because the monitors will need to be able to handle the proper frequency.

More research is definitely necessary.

If you're lucky, you might find one of us old geezers running a TV repair shop near you and they should have the skills to fix them (given a system for a signal source).

If they are 16-bit systems, as has been mentioned, it might be easier to get ISA VGA cards (I have about 30 or so) and used VGA monitors. I doubt that the software would be graphic intensive or smart enough to care what display it's running on.

Option one is iffy, due to parts availability beyond transistors and/or ICs, such as flybacks, yokes, etc.

Option two would be fast, relatively painless and easier on the eyes, IF there isn't something in the software that prevents it.

Wizard260
November 25th, 2008, 07:00 PM
If memory serves me correctly, CGA/EGA/XGA/SXGA(?) had DB 9 connectors, VGA was the first to use the DB15 connector. CGA cards also allowed composite video on RCA type connectors.

You could run a EGA monitor on a CGA card, but not a CGA monitor on a EGA card. I might have that mixed up.

JohnElliott
November 26th, 2008, 03:24 AM
You can run a CGA monitor on an EGA card -- you just have to set the DIP switches right. You don't get the 350-line modes, of course.

november
November 26th, 2008, 04:47 AM
I still haven't heard back from my co-worker.

He did take 2 pictures for me...that did absolutely nothing.

Gotta love telling someone exactly what you need and them giving you shit.

Druid6900
November 26th, 2008, 11:15 AM
Gotta love telling someone exactly what you need and them giving you shit.

Perhaps a tragic, but, fatal "accident" is called for :)

per
November 26th, 2008, 12:06 PM
If memory serves me correctly, CGA/EGA/XGA/SXGA(?) had DB 9 connectors, VGA was the first to use the DB15 connector. CGA cards also allowed composite video on RCA type connectors.

You could run a EGA monitor on a CGA card, but not a CGA monitor on a EGA card. I might have that mixed up.

As said earlier you can run a CGA display on an EGA adapter, but I don't know about a EGA monitor on a CGA adapter. There is an old monitor (90% sure it is EGA) stacked on top of a shelf in my nature science classroom. This monitor got a swich named "invert" on the back side. Maybe this might have been to enable it running off a CGA card (as of the sync signal is opposite voltage on the EGA than the CGA).