I fix the errors i read about the Datanetics Keybord that made from Mike Willegal.
I remove the matrix vias from up left corner (red color).
Also i add vias on Ic's holes and keys. (blue color)
And at the end i fix the sort on the trace by makeing a loop around. (yellow color)
Here is a photo.
You should post the files so people can order the fixed board. Also, if you are handy and enjoy layout, I would be forever grateful if you could create a version with cherry mx switches instead of the dc51. I have all of the stuff (including the pcb, as you pictured) to build the keyboard, however I don't really want to waste the valuable switches on this keyboard.
Not exactly what you ask but may be also an option.
There are some replacements for the anciant chip on the Datanetics availibe. https://www.ebay.com/itm/133723486639
Thanks for the links. I recall reading about that keyboard. It's a good idea, but I was hoping for one that looks exactly like the datanetics one, without the old switches. I am sure it's just me who wants that. I don't think you would be able to tell it isn't the same switches if you got some cherry mx reds with retro keycaps.
I have a small amount of the original encoder ic chips, but it's good to know a modern replacement is available. All of these parts are starting to fail because of age. It's sad.
I know about two Germanys that just build one with mx switches by modifying the original PCB (drilling).
I found some pictures of the URK: http://osiweb.org/osiforum/viewtopic.php?f=3&t=492&start=10#p3472
I'm one of the two "drilling" Germans;)I drilled out the matrix and soldered Cherry MX keys with lots of solder bridges from below.It would be nice if the PCB layout could be adapted to modern Cherry MX keys.
That Datanetics PCB keyboard that you made with Cherry MX switchs came out really great. Plus I didn't no about the MM5740AAE/N replacment I must try and get one for an Apple II computer I have that uses the MM5740AAE/N IC be good to get a spare replacement.
I made a couple of Dave's Universal Keyboard and got a couple of his keyboard key sets he got made. very happy how they came out otherwise I would of gone for a Datanetics PCB keyboard like you.
This is the first Apple 1 I made
This is the second Apple 1 same keyboard but making a case to enclose it in.
Sure. Here are the link with the gerber files:
Attached - Tom
Are these gerbers for Cherry MX switches?
Any idea where to find the correct keycaps, all in black, style really like on the old keyboards?
that eBay link is broken. Could it be possible to know where to find it nowadays?
Also, I'd have a question. In the BOM of the build document it mentions "MM5740 AAE". I can find othere references as MM5740 AAE/N, MM5740 AAD/N or MM5740 AAC/N... Are these equivalents?
I'd have a question about your keyboard.
As far I could see, the Cherry MX switches have a plastic cilinder in the bottom. What did you do with that in your keyboard? Did you cut that part?
Screenshot 2022-02-15 at 09.15.02.png
Can you please confirm this Gerber is correct? When I upload it in JLCPCB it's like the bottom cooper layer is taken as a silkscreen.
Loading it in PCBWAY also seems incorrect when checking it with the Gerber view
I know the OP didn't visit this often, but I'd like to day that I ordered these PCBs and, apart of a problem with the labels of the layers in the Gerbers, I see that the vias in the top left corner aren't really removed, so the drilling is still needed.
I will still try to make a keyboard using this as a base, using ALPS swtiches, which also need additional drilling as the pads don't match. It will need also a lot of bodges, as I know several holes will affect some traces.
Far from ideal, but I'll just see how far I can go.