HB-F1XD keyboard PCB

Master (210)

16-10-2021, 09:47

I recently bought a HB-F1XD from a Japanese seller. Beautiful machine.

It was marked defect/junk and indeed it had some issues. The electronics (HIC board) were quickly repaired. The keyboard membrane however gave me a big headache. Battery acid had gotten in it and ate away the bottom left of the cover film and underlying tracks. I tried repairing it with a silver pen and initially I succeeded but it was all too brittle and when I covered it with transparent nail polish the hairs of the nail polish brush damaged even more tracks. I noticed this only after the nail polish had dried.

Of course not ready to give up I went another way. I saw this great video on YouTube.

So I fired up KiCAD and started designing. You can see the result over here:

I will do some final checking and if all looks good I will order a 0.4mm PCB from JLCPCB. The minimum order size is 5 so if someone is interested let me know.

N.B. This is a thin PCB not a membrane.

By Wierzbowsky

Guardian (3596)

16-10-2021, 09:53

Good job! It would be nice to have an alternative to membranes. There is already the design like that in Japan, but the seller wants 70$ for it. Crazy...

By sdsnatcher73

Prophet (3951)

16-10-2021, 19:41

I have one of these Japanese PCB’s (as both of you know). If you want to look at it to compare with your design before sending out the order that is perfectly fine with me. I am also interested in getting 2 boards if they work well, there are always Sony machines on sale and having options to get them restored are welcome. (and I already have 5 with some form of keyboard issue)

By sdsnatcher73

Prophet (3951)

17-10-2021, 17:40

(And if noone wants the other 2 I am glad to take them as well but I want to give other people a chance as well of course).

By S0urceror

Master (210)

17-10-2021, 20:31

Okay, an update. I printed my PCB design on my normal printer and put the old see-through membrane on top of it to see if everything aligns correctly.

The key contacts and mounting holes are now at the right place. Things look good so far. I am busy putting the finishing touches on it. The routing is done based on the Sony schematics and the DRC is 100% okay according to KiCAD. As long as the schema is correct The PCB should work.

Here is the latest incarnation:

Check here for hi-res version.

Checked also JCLPCB. With a thickness of 0.4mm the PCB costs around EUR 90 per 5 and EUR 120 per 10 including shipping to The Netherlands. I guess I'll do 10 so that I can make more MSXers happy. Don't have to make money on it. As long as I get my investment back I'm fine. 70$ per finished PCB (excluding shipping) is indeed a bit crazy.

@SDSnatcher73, don't know where you live but it would be good to do some comparison before I place the order. How for example your PCB's are connected to the mainboard? With a flexcable or with a normal flat cable and an extension PCB? I'll try to reach you direct to coordinate.

By Valken

Resident (50)

18-10-2021, 10:28

Hello.
If you order a keyboard PCB, I am volunteer to get 1.

Greetings

By Wierzbowsky

Guardian (3596)

18-10-2021, 10:58

What I am afraid of is that the large 0.6mm PCB with so many holes will be too fragile. And it could easily break if even slightly bent. Also, if the board is not gold-plated, the oxidation may result in bad conductivity at some point.

By Valken

Resident (50)

19-10-2021, 21:38

I ordered the part in auction yahoo.

By S0urceror

Master (210)

06-11-2021, 11:03

Got the keyboard PCBs from the manufacturer. See the pictures.

and

I am now waiting for some connectors and ribbon cable. Will get them next week and then it’s the moment of truth I’ll connect all to the Sony HB-F1XD.

I put one of the PCB’s already in the keyboard holder and the keystroke feel good. Good response. And the keyboard itself is pretty sturdy. I expect now problems.

Can’t wait to do the final test. I'll update you all when I'm done.

P.S. I ordered 5 PCBs but got 8.

By erpirao

Paragon (1315)

06-11-2021, 21:17

I would be interested in a pcb to test with my f1xv, could I still ask you for one?
How much would it cost?

By sdsnatcher73

Prophet (3951)

06-11-2021, 21:23

Looks really nice!