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Sony F1-XV/XD/XDJ Keyboard Membrane Rev1.1
Copyright (c) 2025 RBSC
Last updated: 03.10.2025
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About
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Keyboard membranes are always difficult to replace when they get damaged. Finding original membranes these days is
almost impossible and commercially produced membranes are usually very expensive (up to $65 per piece). Creating a
keyboard membrane project is not trivial. First you have to have a good A3-size scanner, then you have to import
the high resolution picture into a CAD program and start manually drawing all pads and tracks. Then you create
necessary holes and outline. But there's one problem - you can't really make a cheap prototype to see if everything
was done correctly. The minimum order is 5 pieces and most of factories will charge at least $70 for such order
excluding shipment.

The RBSC group strongly believes that open-source projects are good for the MSX community and most of our projects
are open-source. This project is not an exception. Keyboard membranes are fragile and sometimes even a strong push
onto a keyboard could damage tracks of a membrane. Water and other liquids can also cause irreversible damage to a
membrane. But with open-source projects anyone can create a replacement for a broken membrane and to sell the rest
to cover the expenses.

This membrane's creation was inspired by Danzk's example - when he created an open-source membrane project for the
Sony HB-F1 MSX computer. The related topic on msx.org could be found here:
https://www.msx.org/forum/msx-talk/hardware/sony-hb-f1-membrane-replacement-pcb

This project was also a learning experience because it was created in KiCAD - the CAD that was not used for our
projects before. We used to make our boards in Eagle CAD, but switching to KiCAD was something that we always wanted
to achieve. This CAD is open-source and offers way better design experience and tools than Eagle CAD.

This membrane should fit 3 different computers: Sony F1-XV, F1-XD and F1-XDJ. But, as stated above, it was not yet
produced and used in any of these computers. When this happens, the project will be updated if necessary.

The topic for this project on msx.org could be found here:
https://www.msx.org/forum/msx-talk/hardware/sony-hb-f1xxx-keyboard-membranes


Other projects
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There's a project by SOurceror that is a thin circuit board for Sony HB-F1XD computer to replace a membrane. It could
be found here:
https://github.com/S0urceror/HB-F1XD-keyboard

The above-mentioned membrane that was created by Danzk for Sony HB-F1 could be found here:
https://github.com/AlexanderKnapik/HB-F1-MSX-Membrane


Ordering
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Please note that ordering a keyboard membrane is not the same as ordering a pcb. The thickness of a membrane is very
important and should be 0.2mm for this membrane. A thinner membrane will be unusable with the MSXs keyboard connector.
There's also such thing as "stiffener" that thin membranes may need to have. But not this one, so don't select it.
Don't select "EMI Shielding Film" either. For cutting select "Laser cutting" - it is much more precise.

When ordering a membrane a factory doesn't usually give you a choice, so they will always make them gold-plated. That
brings the production costs up more than twice. If someone figures out how to produce membranes without ENIG, please
contact the coordinator of the RBSC and share your experience.


IMPORTANT!
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The RBSC provides all the files and information for free, without any liability (see the disclaimer.txt file). The
provided information, software or hardware must not be used for commercial purposes unless permitted by the RBSC.
Producing a small amount of membranes for personal projects and selling the rest of the batch is allowed without the
permission of RBSC.

When the sources of the tools are used to create alternative projects, please always mention the original source and
the copyright!


Contact information
-------------------

The members of RBSC group Tnt23, Wierzbowsky, Pyhesty, Ptero, GreyWolf, SuperMax, VWarlock, ALSP and DJS3000 can be
contacted via the group's e-mail address:

info@rbsc.su

The group's coordinator could be reached via this e-mail address:

admin@rbsc.su

The group's website can be found here:

https://rbsc.su/
https://rbsc.su/ru

The RBSC's hardware repository can be found here:

https://github.com/rbsc

The RBSC's 3D model repository can be found here:

https://www.thingiverse.com/groups/rbsc/things

-= ! MSX FOREVER ! =-