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Welcome to
The Poor Man's Grey Scale Project
Presented by Stuart Bell (stuartsmacs at dsl dot pipex dot com)
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This is an attempt to produce a Mac SE/30 with a grey-scale display by using the electronics of an Apple 12" monochrome monitor within the SE/30's case. |
The initial plan was this: SE/30 drives PDS video card; 640 x 480 o/p from video card drives the electronics of a 12" Apple mono monitor which have been mounted in an SE/30. The monitor electronics drive the CRT PCB and yoke from a 12" monitor which have been mounted on the standard SE/30 9" CRT. All fits inside an SE/30 case, so you end up with a grey-scale display - running at 640 x 480!
[Legal notice for those in litigious countries: Trying to do what I describe here could, if you get it wrong, kill you, fry the cat, or even damage an SE/30. This description does not constitute a recommendation that you follow it. Be careful or be dead. You have been warned. OK? ;-) ]
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Initial explorations using a 12" monitor and connecting its electronics to the 9" CRT of an SE/30:
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The old mono monitor that was used was model M0400, without a captive video lead. Others may work, but I don't have one to test.
Internal view of the 12" monitor; CRT central, PSU to the right of the photo and analogue board to the left. The latter two parts will have to be installed in the SE/30's case eventually.
The 9" CRT from the SE/30 residing and working in the chassis of the 12" monitor, showing electronic compatibility. The display needs fine tuning, I got the yoke on at an angle, but the display is a genuine 640 x 480 grey-scale on an SE/30 9" CRT.
Monitor's yoke and CRT PCB on SE/30's CRT. |
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The SE/30 with 640 x 480 grey-scale display! The display is sharp and clear, but fails to use the full width of the screen. All adjustment has been 'used up'. However, I suspect that driving the display at 60Hz rather than 67Hz may solve the problem. I tried this with the 9" CRT in the 12" monitor chassis, and that's what happened. At the moment, of course, the SE/30 is really only 9" grey scale monitor, as the main SE/30 components have not been reinstated. |
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Re-design time!
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Finding out about a 'Classic475' design from Japan which someone in Germany had also produced caused a re-direction of this project: To put a 475 logic board in the 'grey-scale' SE/30, and thus gain a significant increase in performance and memory size. A significant benefit is that no video card will be needed with the 475 board (unlike the native SE/30 board) because the former will produce the 640 x 480 grey-scale display we want. |
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Stage 1: using the project so far (effectively a 9" 640 x 480 grey scale monitor in an SE/30 case) as the display for an LC475, to check compatibility. All is well! |
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Stage 2: It took three hours playing 'jigsaws' with the basic components to find a layout that would work. If only the SE/30 was 1" wider! The components are: video analogue board (which has to go horizontally under the CRT, unless you want to start lengthening the many cables to it), the HD, the video PSU and the 475 PSU. You also have to consider cable runs - some layouts I tried would have meant a SCSI cable running all around the machine. The key was the HD - placed 'connector down' where PDS cards usually go. |
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Thus, the data and power connectors for the HD are accessible from under the the main horizontal sheet of the chassis, meaning that the cable run to the logic board will be very easy. |
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Stage 3: Everything is set up to check out the connections, with no attempt to fit everything inside the SE/30. |
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Stage 5: The 475 PSU is very compact, but quite long. You can't fit it and the video PSU on the same side of the video card. So, the 475 PSU will fit vertically next to the HD quite happily. |
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The DC outputs from the 475 are then brought out to a 'chocolate block' screw terminal connector glued to the side of the PSU. From there, power goes (a) to the HD and (b) to the main logic board, using the custom connector removed from the PSU leads. |
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Stage 6: The video board is located centrally under the CRT, and the video PSU goes on the other side. |
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Stage 7: The brightness and contrast controls go on the PSU. |
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Yep - it's a genuine grey-scale display on an SE/30 screen - 640 x 480 as well.
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Yet to be sorted: 1. Mains supply from a socket on the back of the case to both PSUs. 2. Video connectors from logic board to video board made all internal. 3. Sense wires worked on to allow operation at 60Hz to fill full width of screen. 4. Fan installed. Stuart Bell |
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