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Printed Circuit Boards

When I started the MTXPlus+ project, I only ever saw it as a hobby project for myself, even when Martin came on board, I didn't really plan on making a "product" out of it - and still don't! In the unlikely event that anyone is interested in making their own MTXPlus+, all of the required information to build your own is freely available on the pages of this website.

In addition to the individual components, all you need is a few Eurocard size prototype boards, copious amounts of prototype wire, a soldering iron and lots of patience. That said, the "novelty" of wiring up prototype boards soon wears off and is likely to be a barrier to anyone even contemplating building MTXPlus+. In my own case, even though I now have a set of working prototype boards that were used during development of the design, I think that using "proper" PCBs is likely to mean that I can probably get more speed out of MTXPlus+, even using the same components.

I am considering getting a very limited run of PCBs made and could offer them for sale at pretty much cost price. As a bare minimum, a set of MTXPlus+ boards would consist of a backplane (with integral power components), CPU, Video and I/O boards, i.e., 4 PCBs. I think that I could probably make a full set of boards available for around 30, not including the components.

If you would be interested in obtaining a set of boards, please drop me an e-mail and I will see whether this becomes a viable option. I don't expect a definite commitment to buy from you, but it would be good to know whether there is any demand for a set of professionally made PCBs.

Martin is also working on a single, ATX sized, MTXPlus+ board that may, or may not, make it into production. Let me know if this is something that you might be interested in too. A single board may work out slightly cheaper, but, being less modular, may be more difficult to test and is potentially less flexible.

PCB BoM  
System Backplane - 5 slots

First PCB Revision - Version 1.11
(To do)
Errata

Although the slot spacing is adequate, it would be better to make the board a little longer (more expensive) and allow more clearance between slots
1. General - slot pitch
2. Q1
3. R3
4. F1
5. C3
6. Boost Regulator
Increased separation might be better
Wrong footprint - too small
Lead pitch too small
Tight clearance with U1, Q1 & R3
Clash with U1 (wrong stencil used)
Vin+ and Vin- reversed
CPU Board (Z80)

First PCB Revision - Version 2.30
(To do)
Errata

Minor errors
1. Routing error
2. VCC and VSS planes
Erroneous RA16 and OA16 link
Missed off Gerber files - oooops!
Video Board (V9958) KiCAD 3D rendering of Video board PCB.

Undergoing final checks before manufacture 
I/O Board    
Co-processor Board (6502) - Future    
CPU Board (Z180S) - Future    
     
     
     

 

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