[Emc-users] OT: Convert CRT to LCD

Discussion:

Rick Lair

2015-09-22 13:42:51 UTC

Hello Guys,

This is off topic for sure, but knew of no better place to ask with all
the electronics knowledge floating around here.

On our big vertical lathe, it has an old 9" CRT that is starting to give
us troubles, and I would like to convert it to an LCD, the only problem
is, that I am having a hard time figuring out the signaling going to the
new monitor. It is a Fanuc control, so it has a Honda 20 pin male
connector going to the CRT unit, which I scavenged up the diagram for
the pin-out. I have 20 pin female connectors here already, so I can make
a patch cable to VGA to connect it to the new monitor, but the signals
are different from one to another. The current CRT has Hsync, Vsync, and
a single wire Video signal, along with three 0V wires in the harness,
and on a separate connector, the power for the monitor. But a standard
VGA has Red, Green, Blue, then Hsync, and Vsync, and a few GRD connections.

Maybe I need a signal converter, I have found quite a few of them on
eBay, or can I just make up a cable and run with it?
--
Thanks

Rick Lair
Superior Roll & Turning LLC
399 East Center Street
Petersburg MI, 49270
PH: 734-279-1831
FAX: 734-279-1166
www.superiorroll.com

------------------------------------------------------------------------------

Leonardo Marsaglia

2015-09-22 13:56:52 UTC

Permalink

Hello Rick.

Sounds like it has the same signals as our Mazak. Probably the working
frequencies are the same as the CGA old monitors. In our case we replaced
the old CRT with an old CGA monitor and connected the video signal to one
of the colors.

But in your case I guess the best would be to get an adapter card from CGA
to VGA. If you have a scope the best you can do is to measure the frequency
of both vertical and horizontal and you can be sure that you have the CGA
values.

Be careful with the adapter boards because I bought one that had problems
with the input on the CGA port so It wouldn't work. Finally a really nice
guy named Roy wich I can't remember his website sent to me a board that he
manufactured for US 45 and worked fine, really well made I have to say. We
are not using it at the moment because the CRT monitor that we installed is
working ok but in case of a failure we have the board for replacement.

Post by Rick Lair
Hello Guys,
This is off topic for sure, but knew of no better place to ask with all
the electronics knowledge floating around here.
On our big vertical lathe, it has an old 9" CRT that is starting to give
us troubles, and I would like to convert it to an LCD, the only problem
is, that I am having a hard time figuring out the signaling going to the
new monitor. It is a Fanuc control, so it has a Honda 20 pin male
connector going to the CRT unit, which I scavenged up the diagram for
the pin-out. I have 20 pin female connectors here already, so I can make
a patch cable to VGA to connect it to the new monitor, but the signals
are different from one to another. The current CRT has Hsync, Vsync, and
a single wire Video signal, along with three 0V wires in the harness,
and on a separate connector, the power for the monitor. But a standard
VGA has Red, Green, Blue, then Hsync, and Vsync, and a few GRD connections.
Maybe I need a signal converter, I have found quite a few of them on
eBay, or can I just make up a cable and run with it?
--
Thanks
Rick Lair
Superior Roll & Turning LLC
399 East Center Street
Petersburg MI, 49270
PH: 734-279-1831
FAX: 734-279-1166
www.superiorroll.com
------------------------------------------------------------------------------
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Emc-users mailing list
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--
*Leonardo Marsaglia*.
------------------------------------------------------------------------------

Leonardo Marsaglia

2015-09-22 14:00:38 UTC

Permalink

Also note that VGA works with analog voltages for the RGB and the CRT on
your lathe sure has TTL for the video signal so it wouldn't work without
and adapter board.

Post by Leonardo Marsaglia
Hello Rick.
Sounds like it has the same signals as our Mazak. Probably the working
frequencies are the same as the CGA old monitors. In our case we replaced
the old CRT with an old CGA monitor and connected the video signal to one
of the colors.
But in your case I guess the best would be to get an adapter card from CGA
to VGA. If you have a scope the best you can do is to measure the frequency
of both vertical and horizontal and you can be sure that you have the CGA
values.
Be careful with the adapter boards because I bought one that had problems
with the input on the CGA port so It wouldn't work. Finally a really nice
guy named Roy wich I can't remember his website sent to me a board that he
manufactured for US 45 and worked fine, really well made I have to say. We
are not using it at the moment because the CRT monitor that we installed is
working ok but in case of a failure we have the board for replacement.

--
*Leonardo Marsaglia*.

--
*Leonardo Marsaglia*.
------------------------------------------------------------------------------

Rick Lair

2015-09-22 14:19:39 UTC

Permalink

Would something along these lines work?

http://www.ebay.com/itm/Brand-NEW-MDA-RGB-CGA-EGA-to-VGA-industrial-Converter-/250851103017?hash=item3a67e41129

Post by Leonardo Marsaglia
Also note that VGA works with analog voltages for the RGB and the CRT on
your lathe sure has TTL for the video signal so it wouldn't work without
and adapter board.

--
*Leonardo Marsaglia*.

--
Thanks

Rick Lair
Superior Roll & Turning LLC
399 East Center Street
Petersburg MI, 49270
PH: 734-279-1831
FAX: 734-279-1166
www.superiorroll.com

------------------------------------------------------------------------------

Leonardo Marsaglia

2015-09-22 14:23:42 UTC

Permalink

Post by Rick Lair
Would something along these lines work?
http://www.ebay.com/itm/Brand-NEW-MDA-RGB-CGA-EGA-to-VGA-industrial-Converter-/250851103017?hash=item3a67e41129

I guess that board woul work ok since it looks a lot better than mine. If
you have the CGA frequencies you should have no problems.

Mine was the same as this:

http://www.ebay.com/itm/NEW-Arcade-game-RGB-CGA-EGA-YUV-to-VGA-HD-video-converter-board-HD9800-GBS8200-/170860805754?hash=item27c818fe7a

--
*Leonardo Marsaglia*.
------------------------------------------------------------------------------

Rick Lair

2015-09-22 14:27:51 UTC

Permalink

Looking at the one print I found for my machine, it looks like Hsync
15.87 Khz, and Vsync 54.39 Khz,

Rick

Post by Leonardo Marsaglia

Post by Rick Lair
Would something along these lines work?
http://www.ebay.com/itm/Brand-NEW-MDA-RGB-CGA-EGA-to-VGA-industrial-Converter-/250851103017?hash=item3a67e41129

I guess that board woul work ok since it looks a lot better than mine. If
you have the CGA frequencies you should have no problems.
http://www.ebay.com/itm/NEW-Arcade-game-RGB-CGA-EGA-YUV-to-VGA-HD-video-converter-board-HD9800-GBS8200-/170860805754?hash=item27c818fe7a

Lester Caine

2015-09-22 14:51:25 UTC

Permalink

Post by Rick Lair
Looking at the one print I found for my machine, it looks like Hsync
15.87 Khz, and Vsync 54.39 Khz,

Hopefully Vsync is 54Hz ... needs to be substantially less than HSync.
The quick trick used to be hooking up the H and V to the VGA monitor,
and then simply wiring R, G and B together to give you a 'white' signal,
but modern monitors tend to be a little less forgiving with lower
frequency signals, but it should lock at 15.87KHz so I'd just give it a go.
--
Lester Caine - G8HFL
-----------------------------
Contact - http://lsces.co.uk/wiki/?page=contact
L.S.Caine Electronic Services - http://lsces.co.uk
EnquirySolve - http://enquirysolve.com/
Model Engineers Digital Workshop - http://medw.co.uk
Rainbow Digital Media - http://rainbowdigitalmedia.co.uk

------------------------------------------------------------------------------

Gene Heskett

2015-09-22 14:51:48 UTC

Permalink

Post by Rick Lair
Looking at the one print I found for my machine, it looks like Hsync
15.87 Khz, and Vsync 54.39 Khz,

I suspect you meant 54.38 Hz. That would be within the reach of an NTSC
monitor. Unfortunately those are limited to those tv's with inputs for
old DVD's and VCR's, neither of which is near sharp enough to do what
you want. That would imply a dot frequency in the 15 megahertz region,
and a GBS8200 video adapter, about 35-40 bucks that the game console
folks use so they can replace the failing CRT's in the coin-op game
consoles with modern but vga only LCD monitors. The inputs on that are
such that the worst adaptation you might have to do is invert the sync.
Almost any TTL inverter can handle that. I don't know how that board
might react to the 5 Hertz diff in vsync frequency though as the only
place I have used one is on my Color Computer 3, whose sync was not 100%
NTSC compatible. Non-interlaced IOW.

Post by Rick Lair
Rick

Post by Leonardo Marsaglia

Post by Rick Lair
Would something along these lines work?
http://www.ebay.com/itm/Brand-NEW-MDA-RGB-CGA-EGA-to-VGA-industrial
-Converter-/250851103017?hash=item3a67e41129

I guess that board woul work ok since it looks a lot better than
mine. If you have the CGA frequencies you should have no problems.
http://www.ebay.com/itm/NEW-Arcade-game-RGB-CGA-EGA-YUV-to-VGA-HD-vi
deo-converter-board-HD9800-GBS8200-/170860805754?hash=item27c818fe7a

Cheers, Gene Heskett

--
"There are four boxes to be used in defense of liberty:
soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
Genes Web page <http://geneslinuxbox.net:6309/gene>

------------------------------------------------------------------------------

Rick Lair

2015-09-22 15:19:54 UTC

Permalink

Yep 54 hz, not khz, very poor writing on the print that denotes that.

Post by Gene Heskett

Post by Rick Lair
Looking at the one print I found for my machine, it looks like Hsync
15.87 Khz, and Vsync 54.39 Khz,

Post by Rick Lair
Rick

Post by Leonardo Marsaglia

Post by Rick Lair
Would something along these lines work?
http://www.ebay.com/itm/Brand-NEW-MDA-RGB-CGA-EGA-to-VGA-industrial
-Converter-/250851103017?hash=item3a67e41129

I guess that board woul work ok since it looks a lot better than
mine. If you have the CGA frequencies you should have no problems.
http://www.ebay.com/itm/NEW-Arcade-game-RGB-CGA-EGA-YUV-to-VGA-HD-vi
deo-converter-board-HD9800-GBS8200-/170860805754?hash=item27c818fe7a

Cheers, Gene Heskett

Rick Lair

2015-09-22 14:36:03 UTC

Permalink

Attached is a copy of the pinout, the connector is in the red box
pertaining to the crt.

Rick

Post by Leonardo Marsaglia

Post by Rick Lair
Would something along these lines work?
http://www.ebay.com/itm/Brand-NEW-MDA-RGB-CGA-EGA-to-VGA-industrial-Converter-/250851103017?hash=item3a67e41129

--
Thanks

Rick Lair
Superior Roll & Turning LLC
399 East Center Street
Petersburg MI, 49270
PH: 734-279-1831
FAX: 734-279-1166
www.superiorroll.com

Gene Heskett

2015-09-22 17:11:58 UTC

Permalink

Post by Rick Lair
Attached is a copy of the pinout, the connector is in the red box
pertaining to the crt.
Rick

Post by Leonardo Marsaglia

Post by Rick Lair
Would something along these lines work?
http://www.ebay.com/itm/Brand-NEW-MDA-RGB-CGA-EGA-to-VGA-industrial
-Converter-/250851103017?hash=item3a67e41129

I guess that board woul work ok since it looks a lot better than
mine. If you have the CGA frequencies you should have no problems.
http://www.ebay.com/itm/NEW-Arcade-game-RGB-CGA-EGA-YUV-to-VGA-HD-vi
deo-converter-board-HD9800-GBS8200-/170860805754?hash=item27c818fe7a

There was a link from that to another one at $19, free ship. It should
do the job.
<http://www.ebay.com/itm/NEW-Arcade-Game-RGB-CGA-EGA-YUV-to-VGA-HD-Video-Converter-Board-HD9800-GBS8200/131521336573?_trksid=p2047675.c100005.m1851&_trkparms=aid%3D222007%26algo%3DSIC.MBE%26ao%3D1%26asc%3D33421%26meid%3Dfd2abb8a85f744b5bd6e72e24b67e114%26pid%3D100005%26rk%3D1%26rkt%3D6%26sd%3D170860805754>

It should do the job.

Cheers, Gene Heskett

Gene Heskett

2015-09-22 14:35:33 UTC

Permalink

Post by Rick Lair
Hello Guys,
This is off topic for sure, but knew of no better place to ask with
all the electronics knowledge floating around here.
On our big vertical lathe, it has an old 9" CRT that is starting to
give us troubles, and I would like to convert it to an LCD, the only
problem is, that I am having a hard time figuring out the signaling
going to the new monitor. It is a Fanuc control, so it has a Honda 20
pin male connector going to the CRT unit, which I scavenged up the
diagram for the pin-out. I have 20 pin female connectors here already,
so I can make a patch cable to VGA to connect it to the new monitor,
but the signals are different from one to another. The current CRT has
Hsync, Vsync, and a single wire Video signal, along with three 0V
wires in the harness, and on a separate connector, the power for the
monitor. But a standard VGA has Red, Green, Blue, then Hsync, and
Vsync, and a few GRD connections.
Maybe I need a signal converter, I have found quite a few of them on
eBay, or can I just make up a cable and run with it?

Those 0 volt wires are more than likely shielding returns to be grounded
and could likely be combined at the grounded terminal of the db15, so
you could probably knock out a merging pcb on the mill in half an hour
or so. The 9" I have to assume was black & white? That, in todays all
color lcd's might have to be buffered with a gain control and
resistively fed to all 3 colors on the vga cable. See the TI opamp
selections for the buffer as they have a good selection of video speed
opamps that can run on a single 5 volt supply, for something in the sub
$2 price. I used several of them as replacements for a custom circuit
in a GVG video switcher that the Grass Valley Group wanted $1500 a copy
for, and they were actually faster than theirs was. 15 Years ago, so
the stuff is available. I'd quote the Jedec number but have forgotten
it.

You want a single 5volt supply unit with a gain/bandwidth product of a
about a gigahertz for that.

Cheers, Gene Heskett

Gregg Eshelman

2015-09-23 01:19:14 UTC

Permalink

Those old monochrome monitors would be some variety of digital TTL
signaling instead of the analog signaling VGA used.

I'd bet it's not the same as the TTL method IBM used on their old mono
monitors.

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