IBM 5153 Monitor EGA Modification

[ctrl-alt-rees]

I recently acquired an IBM 5150 with 5153 monitor. I've been looking into an EGA upgrade and of course the highly desirable 5154, although this monitor is pretty much impossible to come by in the UK.

Then I stumbled across this - a fairly straightforward-looking mod to allow EGA on the 5153: http://www.worldphaco.com/uploads/INCREASING_THE_UTILITY_OF_THE_IBM_5153_COLOR_MONITOR_TO_AUTO.pdf

I have a lot of electronics and soldering experience as well as working with CRTs and I'm considering giving it a try. But just before I take the plunge I wanted to ask if anyone here had attempted it? Apologies if this has been discussed already but nothing came up in my searches for various combinations of "5153" and "EGA". Thanks!

 

[Trixter]

Hugo, the person who wrote the document, has not only tried it, but is a member of this forum. You could send him a PM if you have questions.

 

[alank2]

I would be completely interested in doing this mod as well if the pcb is easy to order/make and components are available.

 

[cwathen]

I recently acquired an IBM 5150 with 5153 monitor. I've been looking into an EGA upgrade and of course the highly desirable 5154, although this monitor is pretty much impossible to come by in the UK.

I did manage to get hold of a 5154 monitor in the UK. As usual with them, bad caps which I've not got around to replacing yet. TBH I think I'd rather have had a 5153, they seem to be a lot more reliable.

 

[Malc]

I don't know, I have replaced caps in my 5153 and 5154 PSU's, I also had to replace a cap on the mainboard in one of them because of vertical collapse but can't remember which one it was now, Reliability wise pretty much equal, I've had them for years. 5154's turn up on Ebah UK now and then but 5153's are more common, Seller's want lots of money for them these days.

 

[VileR]

Hopefully it's clear that this mod does not support full EGA color - as noted in the document, colors that fall outside the CGA range won't display correctly.

 

[Hugo Holden]

Yes, that is right, but mostly the 16 colours are enough for a good result. As you can see in the article it reproduced the Vega video-7 EGA test screen normally.

The main utility of it is that if your video card (if an EGA/CGA type..I use the Video7) flicks into EGA mode you can keep using the computer without being blindsided by a scrambled screen. The video 7 card for example, used in CGA mode has a 16 color 640 X 200 mode that you can't get out of a standard CGA card which is why I like it.

As mentioned in the article, I don't think the construction quality of a 5154 is as good as a 5153. The ventilation was poor, the PCB cooks up in the region of the video output amps and the vertical output stage, it shortens the life of the electrolytic caps there too.So I didn't warm to it. However, the 5154 was a revolutionary design concept and when working is great performer and its EGA images would be very hard to beat and much better than my mod to the 5153. I like the way the 5153 was physically built though.

The modification I did to get the 5153 to display a reduced size EGA image could be made up as a kit for the 5153, but I am not in a position to do that, However, there maybe somebody who would want to provide it to other forum members.

...ps: depending on the Video-7 card switches, some software can be blocked from flipping the card into EGA, for example, in BASIC, if you try to change to screen 9 (EGA screen) it will report an illegal function call if the card switches are set for CGA. But other software I have can still flip the Video 7 card to EGA, regardless of its switch settings.

 

[alank2]

Hugo do you have gerbers for this / BOM ? I recall asking someone about this a couple weeks ago so if I'm asking you again, my apologies.

 

[Hugo Holden]

Hugo do you have gerbers for this / BOM ? I recall asking someone about this a couple weeks ago so if I'm asking you again, my apologies.

It's seems odd, but my projects with pcb's never have any Gerbers. I simply draw the PCB as a jpeg image in Microsoft Picture IT. Then my PCB maker has some sort of image capture program, that imports the image into Altium (PCB software I don't have) then he makes the PCB for me. Apparently many PCB makers can do this, and agree to make pcb's just from an image of the artwork.

 

[ctrl-alt-rees]

Thanks for the replies everyone. Lots to think about. I do have a 486 with a VGA card that I use for EGA games and software so perhaps I'm best sticking with CGA on the 5150.

My PC and monitor are both US imports so I'm not against importing a 5154 from the US if one comes up at the right price. Will keep an eye out for one.

 

[Malc]

I use VGA in all my old IBM's with the exception of my 5155, I prefer using LCD's these days, Better for my poor old eyes, Having them imported must be a tad on the expensive side.

 

[deathshadow]

I use VGA in all my old IBM's with the exception of my 5155, I prefer using LCD's these days, Better for my poor old eyes, Having them imported must be a tad on the expensive side.

Yeah whilst having proper period correct is "cute" it's often just not worth it. I've been really partial to certain viewsonic and dell 4:3 aspect LCD's for my 'middling' machines for some time. Both makers did some excellent work in how their scale converters handle the odd pixels, particularly on the 1280x1024 and 1600x1200 ones.

The Viewsonic 17" VP171b in particular is an amazing display for standard 640x480 VGA since it's 2x horizontal and 2.13333x vertical resolution. I've got two of them, and they see use all the time, even as secondary displays on my garage machine when I need more desktop space since they pivot.

Dell's 20" 2001FP is even better since it's got both composite and SVHS in with an amazing scan converter, in addition to VGA and DVI. It even syncs to CGA and EGA frequencies to the point all you need is a cable converter and 2 bit ladder DAC's to turn the RGBI or RGBrgb into the proper output levels. (they even used to sell cables for that!). First one I ever got did double-duty as my TV during some hard times. Now I own three of them... and it pivots so I can use them too as secondary displays without sucking down too much desktop space.

Even better, both are TFT. None of that dual scan crap.

As much as it's not period correct, it's just easier to go this route... particularly if price and shipping is a concern. Getting a LCD shipped is far less likely to get screwed up than a CRT.

 

[Flamin Joe]

Why not the best of both worlds?

If I had a spare 5153 which was beyond repair I'd investigate further an idea I've had of mounting a suitable LCD inside the chassis. You lose of course the curvature of the tube but if it worked it would be quite a neat looking solution I'd imagine.

As much as I'd love to try I doubt I'd ever have a dead spare to do it as they are pretty rare as it is down under.

 

[ctrl-alt-rees]

Interesting thoughts. I've considered replacing a CRT tube with an LCD panel within the same chassis on a few machines in the past. I think it could be done in a tasteful way and would certainly preseve most of the original "character" of the computer while gaining all of the benefits of TFT (easier on the eyes, more reliable, lower energy consumption, lower weight etc) but I've been very lucky in that I've been able to repair all of the CRT monitors that have come my way so far.

I'm perhaps a little too obsessive about originality and having everything match, but hey, it satisfies whatever undiagnosed mild form of OCD I must have :lol:

On the subject of importing... I've imported quite a few things over the years. Famicom stuff from Japan, Atari and NeXT stuff from the US etc. I've never made a loss when I come to sell it on locally as there always seems to be some "money no object" buyer interested if you check the right places. Particularly as I'm big on restoring everything to pristine condition and having matching manuals, boxes and peripherals. Perhaps I've just been really lucky so far. It helps me justify the expense to myself (and the wife) anyway!

This probably sounds a bit crazy to those in the US when talking about something as common as the 5150 but they really do command top dollar in the UK. Perhaps I should start shipping over containers full of the things. :wink:

 

[dongfeng]

If you can get hold of an EGA card you can adjust the DIP switches to support a 5153 at EGA Mode 1 resolutions - 320x200 and 640x200 IIRC. Yes, it's a halfway house type solution, but works rather well.

 

[per]

As mentioned in the article, I don't think the construction quality of a 5154 is as good as a 5153. The ventilation was poor, the PCB cooks up in the region of the video output amps and the vertical output stage, it shortens the life of the electrolytic caps there too.So I didn't warm to it. However, the 5154 was a revolutionary design concept and when working is great performer and its EGA images would be very hard to beat and much better than my mod to the 5153. I like the way the 5153 was physically built though.

This.

I once came across a pair of 5154's, one with a faulty video amp and one where a shorted cap had taken out the vertical amp. In the end I ended up swapping around the video amp module to get one fully working unit.

 

[ctrl-alt-rees]

If you can get hold of an EGA card you can adjust the DIP switches to support a 5153 at EGA Mode 1 resolutions - 320x200 and 640x200 IIRC. Yes, it's a halfway house type solution, but works rather well.

OK, now I'm intrigued. Is this something supported by all EGA cards or is it specific to IBM EGA cards?

 

[VileR]

OK, now I'm intrigued. Is this something supported by all EGA cards or is it specific to IBM EGA cards?

Wouldn't know about "all", but many/most did (i.e. ATI's EGA Wonder). Those 200-line EGA modes use CGA signalling anyway, so that feature simply does the same for text modes (and disallows hi-res graphics).
EGA (and multisync) monitors weren't cheap, so EGA cards on CGA monitors were a thing.

 

[ctrl-alt-rees]

Wouldn't know about "all", but many/most did (i.e. ATI's EGA Wonder). Those 200-line EGA modes use CGA signalling anyway, so that feature simply does the same for text modes (and disallows hi-res graphics).
EGA (and multisync) monitors weren't cheap, so EGA cards on CGA monitors were a thing.

Thanks for the help, my earliest experiences with PCs were in the early VGA era so I don't have a great deal of experience with CGA / EGA. I'm using this machine as an experience to learn. Is there any benefit to using an EGA card in such a way? I've seen videos on YouTube showing certain games and applications running much faster on EGA on the same hardware despite the improved graphics, presumably due to differences in ways that the card renders the graphics?

 

[VileR]

Is there any benefit to using an EGA card in such a way? I've seen videos on YouTube showing certain games and applications running much faster on EGA on the same hardware despite the improved graphics, presumably due to differences in ways that the card renders the graphics?

If you mean faster than CGA, yep - EGA lets you do things like full-screen double buffering, hardware panning/scrolling, and so on to speed things up. You do need to haul more bytes around compared to CGA, but once they're all in video RAM, there's more you can do without having to rewrite them constantly.

The only time EGA doesn't beat CGA is when you want to run actual CGA software. Any CGA code that bypasses the BIOS interface probably won't work as intended, since most of the EGA's CGA compatibility stops at that level. Certain EGA chipsets might have tried a little harder than IBM did, but I can't think of one that had 'perfect ' CGA emulation really.