Atari 130XE keyboard rebuild: vintage keycaps on modern switches

[+Stephen]

1 hour ago, XL Freak said:

pls disregard the above message. it was mistakenly posted here. sorry folks...

Regardless - best of luck with your surgery and recovery!

[ScreamingAtTheRadio]

What to do when you receive your keyboards

I haven't yet updated the readme file on the repo for the latest revisions, but since the first keyboards are shipping now, I need to provide some guidance about how to install those, depending on what you ordered.

 

A note on the current adapters

The current adapters fit in the case, but require some persuasion. The clearance under the keyboard in XE computers is extremely tight, to the point that to be able to assemble the keyboards on top of the adapter, the connector on the Atari side may have to be gently pushed forward, making sure the solder points don't suffer from that. The FFC cable itself will have to fold at the point it exits the connector (this is fine, those cables are designed to fold).

 

Even doing all that, I'm not super-happy about how tight the whole thing is and how it may lift the keyboard unevenly in some cases.

 

So my recommendation for now is to unsolder the Atari connector from the motherboard and replace it with some pin headers, and then solder the adapter onto those headers parallel to the motherboard. I'll try to post some photos of what that looks like. This should ensure there's plenty of space and no excessive mechanical constraints on the hardware. I understand some of you will prefer not to touch their precious XE motherboards.

 

I have a design in mind for a better adapter that moves the connector sideways to the right of the Atari connector. I'll ship that new design for free to everyone in the first batch of pre-orders who want it. ETA on this: 2-3 weeks for the new adapters to arrive here in Washington state.

 

Modern keyboard (assembled)

If you ordered an assembled modern keyboard, it should be very simple.

 

You may have to separate your printed Fn keys using some nippers and then press fit them on the corresponding switches.

 

The FFC cable should already be attached to the back of the keyboard. Verify the connection is solid and readjust if necessary (the connectors have two tabs on the side that you can pull to free the cable; the cable should be fully inserted with the contacts facing away from the PCB; make sure the tabs are both fully pushed back to ensure a solid connection).

 

[skip to the common section]

 

Vintage keyboard (assembled)

Usually this will come with the adapters for your flavor of vintage keys in a small bag. You'll need to separate each adapter using nippers. The small parts linking the adapters during fabrication are positioned to not get in the way, but it's still a good idea to cut them as flush as possible.

 

Insert each adapter in one of the switches.

 

Use a key cap extractor to remove the keys from your vintage keyboard (a key extractor is the best way to make sure you don't damage the caps). Make sure to be especially gentle if you have the square variant, those break easily.

 

Put the two space bar stabilizer adapters into your vintage space bar. You can set aside the old metal rod for this key, you won't need it.

 

Remove the stabilizer rod for your left shift key. You'll need to slightly bend this so it can go around the new switch and into the new stabilizer. This may require some fiddling. In the worst case, the left shift stabilizer can be omitted if you can't find a way to make it work. This is my least favorite part of those keyboards...

 

Assemble the caps back onto the new keyboard by gently pressing them into place.

 

[skip to the common section]

 

Modern keyboard (kit)

If you ordered a kit, there is a specific order in which you should assemble.

 

Assemble the stabilizers. The stabilizers consist of a larger part that has the threaded part, a smaller part that slides into the previous one, a metal bar linking two assemblies of the two previous parts, and some hardware. The stabilizers are best assembled in this order: slide the smaller part into the larger one (make sure you orient it properly), then insert one end of the metal rod into that assembly and push it into place so it clicks and is properly secured. Once you've done that with both ends of the stabilizer, you should be able to verify both ends lift together and with no friction (some people like to lube their stabilizers by the way).

 

Once the stabilizers are assembled, you can put them in their respective places on the top side of the PCB. Insert the bottom, non-threaded part first, try to lay the stabilizer's surface flat on the PCB, and push the top threaded part into place. This usually moves the other end a bit, so make sure both ends are properly inserted all the way into the holes in the PCB.

 

Turn the PCB over. Position one of the small washers around each of the screw holes for the stabilizers and secure it with a screw. Repeat this for the space stabilizer, the left shift and the return key. Do not do it for the backspace / del key as the screw would get in the way of the FFC connector. This is a minor design flaw that I'll remove in a future revision, but it's fine, the stabilizer won't move if you've properly installed it.

 

Use needle-nose pliers to fold the legs of the power LED to the correct length so the LED when laid flat has its whole body outside of the PCB's perimeter, but just so. The long leg (the anode) goes to the right, its short leg to the left (you can see that pad is connected to the ground plane of the PCB). Solder that in place and cut the extra length of the legs. If you can't find the small jumpers that should have been in your package, you can reuse those cut legs for the next step.

 

Solder two jumper wires to the left of the PCB to configure it for Caps. This rewires the key that's above left shift and that's normally Control on a vintage keyboard. Control on the modern keyboard goes to the left of the space bar, and this key is reconfigured to be Caps. The two wires should short from the middle position to the right position. The silkscreen has helper text for this.

 

Insert switches into the aluminum or aluminium plate depending on whether you are in the US  with the LED window to the back and the pins to the front. The exception to this is the return key that should have its LED window to the right and pins to the left. Note that there are some differences with the vintage layout: the del/backspace key is two units wide, so put the switch in the middle position (there are three positions to accommodate for vintage layouts). Same for return, put it in the middle position among the three available vertically on the right of the board. There are also two additional positions around the space bar, each with its own switch. You might want to not position the del and return switches before the plate is in place as it may move, and it's fine to insert it later.

 

After making sure all the switch pins are vertical and none are bent out of place, carefully align the plate and switches with the stabilizers and the PCB. Slowly and carefully complete that assembly, making sure no pins get bent. Once that is done, the plate and PCB should be a few millimeters apart, more or less evenly spaced across the whole surface. You may want  to secure them together with tape or clothespins until you've soldered enough of them.

 

Solder the switches onto the PCB.

 

Solder the FFC connector in place. This is the only SMT component you'll have to solder. There are several methods to do that, and the 1mm pitch is not too bad. If you're not used to SMD soldering, I'd recommend trying your hand on one of the training boards that you can find online. There's also plenty of tutorials out there to get you started.

 

I recommend at this point to test your work. Get your multimeter and set it in continuity mode, then verify the connection in order between each of the holes next to the FFC connector and the pins of the connector. Directions here assume you put the connector to the bottom-right of your work area. You'll want to touch very gently on the connector side so you don't artificially create a connection by pushing on the pin. Hole one is marked as such on the silkscreen and corresponds to the connector pin closest to it. Once you've got a solid beep for the first pin, move one of your probes to the next hole and check the beeping stops (if it doesn't, that means the pin you were testing and the next are shorted). Hole numbers go like this: move down one hole, then up and left diagonally, then repeat. The pins just go in order going to the left.

 

You should be able to test all the pins this way to pin 24. The connector has two more lines for the LED backlighting. They should be connected to two of the four holes you can see aligned vertically on the board to the right of the connector.

 

And then you're pretty much done for the keyboard itself, just pull the two tabs for the connector, insert the cable all the way with contacts facing away from the PCB, then push the tabs back in.

 

Now you need to assemble your adapter. The process is pretty much a repeat of the procedure to assemble the connector on the main board. To check your work, you'll verify continuity between the connector pins and the edge contacts on the bottom of this little board, in reverse order (start on the left of the edge connector and on the right of the FFC connector). For the last two pins, one is connected to edge contact 1 and the other to the bottom-left contact of the pot that you're going to solder next (look for the three holes to the left of the FFC connector).

 

Solder the small pot. If you don't care about backlighting or about being able to change the intensity, you could leave it open, short it or put a resistor in its place.

 

[skip to the common section]

 

Vintage keyboard (kit)

If you ordered a kit, there is a specific order in which you should assemble.

 

Assemble the space stabilizer. The stabilizers consist of a larger part that has the threaded part, a smaller part that slides into the previous one, a metal bar linking two assemblies of the two previous parts, and some hardware. The stabilizers are best assembled in this order: slide the smaller part into the larger one (make sure you orient it properly), then insert one end of the metal rod into that assembly and push it into place so it clicks and is properly secured. Once you've done that with both ends of the stabilizer, you should be able to verify both ends lift together and with no friction (some people like to lube their stabilizers by the way).

 

Once the stabilizer is assembled, you can put both ends in their respective places on the top side of the PCB. Insert the bottom, non-threaded part first, try to lay the stabilizer's surface flat on the PCB, and push the top threaded part into place. This usually moves the other end a bit, so make sure both ends are properly inserted all the way into the holes in the PCB.

 

Turn the PCB over. Position one of the small washers around each of the screw holes for the stabilizers and secure it with a screw.

 

The left shift stabilizer is more problematic and potentially the most frustrating part of this build. Worst case, it may be fine to just omit this stabilizer because if improperly installed it can make things worse. The stabilizer consists of two plastic parts that should fit into slots around the switch's position. Depending on whether you have circle or square caps, it should be installed upside up or upside down. Those stabilizers are very tricky to put in place. Once they are in place, you'll need (later, we'll get back to that) to get the metal rod from your vintage left shift, remove it, then bend it slightly so it can go around the switch and still be inserted into the new stabilizer. I'm not kidding when I say this is frustrating.

 

Use needle-nose pliers to fold the legs of the power LED to the correct length so the LED when laid flat has its whole body outside of the PCB's perimeter, but just so. The long leg (the anode) goes to the right, its short leg to the left (you can see that pad is connected to the ground plane of the PCB). Solder that in place and cut the extra length of the legs. If you can't find the small jumpers that should have been in your package, you can reuse those cut legs for the next step.

 

Solder two jumper wires to the left of the PCB to configure it for Control. This keeps the vintage layout wiring for the Control key. The two wires should short from the middle position to the left position. The silkscreen has helper text for this and should make it clear you are wiring for Control.

 

Insert switches into the aluminum or aluminium plate depending on whether you are in the US  with the LED window to the back and the pins to the front. The exceptions to this are the delete switch and the break switch that are upside down, and the return switch that has its pins to the right and LED window to the left. If your switches have two smaller legs around the center cylinder, you may have to nip the bottom one so it can get in place correctly.

 

After making sure all the switch pins are vertical and none are bent out of place, carefully align the plate and switches with the stabilizers and the PCB. Slowly and carefully complete that assembly, making sure no pins get bent. Once that is done, the plate and PCB should be a few millimeters apart, more or less evenly spaced across the whole surface. Low-profile switches have a tendency to not attach to the plate as well as full-sized switches, so don't worry if some of these fall out during assembly, you'll have a chance to set them back in later. At this point, you want to have enough to ensure proper alignment. Another thing with low-profile switches is that they're not as good at maintaining the distance between PCB and plate. To make that distane more even with the distance imposed by the space stabilizer, I glue a couple of washers between plate and PCB on the top of the assembly to keep them apart. You may want  to also secure them together with tape or clothespins until you've soldered enough switches.

 

Solder the switches onto the PCB.

 

Solder the FFC connector in place. This is the only SMT component you'll have to solder. There are several methods to do that, and the 1mm pitch is not too bad. If you're not used to SMD soldering, I'd recommend trying your hand on one of the training boards that you can find online. There's also plenty of tutorials out there to get you started.

 

I recommend at this point to test your work. Get your multimeter and set it in continuity mode, then verify the connection in order between each of the holes next to the FFC connector and the pins of the connector. Directions here assume you put the connector to the bottom-right of your work area. You'll want to touch very gently on the connector side so you don't artificially create a connection by pushing on the pin. Hole one is marked as such on the silkscreen and corresponds to the connector pin closest to it. Once you've got a solid beep for the first pin, move one of your probes to the next hole and check the beeping stops (if it doesn't, that means the pin you were testing and the next are shorted). Hole numbers go like this: move down one hole, then up and left diagonally, then repeat. The pins just go in order going to the left.

 

You should be able to test all the pins this way to pin 24. The connector has two more lines for the LED backlighting. They should be connected to two of the four holes you can see aligned vertically on the board to the right of the connector.

 

And then you're pretty much done for the keyboard itself, just pull the two tabs for the connector, insert the cable all the way with contacts facing away from the PCB, then push the tabs back in.

 

Now you need to assemble your adapter. The process is pretty much a repeat of the procedure to assemble the connector on the main board. To check your work, you'll verify continuity between the connector pins and the edge contacts on the bottom of this little board, in reverse order (start on the left of the edge connector and on the right of the FFC connector). For the last two pins, one is connected to edge contact 1 and the other to the bottom-left contact of the pot that you're going to solder next (look for the three holes to the left of the FFC connector).

 

Solder the small pot. If you don't care about backlighting or about being able to change the intensity, you could leave it open, short it or put a resistor in its place.

 

[skip to the "Vintage keyboard (assembled)" section]

 

Common section: inserting the adapter

Remove your existing keyboard, pulling the membrane connector carefully using both hands to avoid accidentally folding it.

 

Insert the adapter (or do the replacement described above). The FFC connector should face the front of the case. There's also a little triangular mark on the part of the adapter that plugs into the Atari; that should be on the left (pin 1).

 

Then position the keyboard to the back of the XE case so you have enough space to work and the cable can reach the adapter's connector. Open the connector, insert the cable with the contacts facing away from the board, then push back the two tabs, making sure the connection is solid and the cable can't move.

 

You can now power your computer. The power LED on the keyboard should go on and the backlighting should too. It's a good idea to go to the diagnostics and try the keyboard diagnostics. I've already done that on all the keyboards I shipped, but you never know what could happen in transit.

 

The little pot on the adapter can be rotated with a small screwdriver. This adjusts the brightness of the backlight LEDs (this can also limit the current the backlighting draws).

 

And that's it. Let me know if you have any questions or need to troubleshoot anything.

Edited March 31, 2023 by ScreamingAtTheRadio

[ScreamingAtTheRadio]

One more thing... If you have a circle vintage keyboard, the return switch will be sideways, but the key won't. That necessitate a modified version of the adapters that's rotated 90 degrees. I don't have this adapter at this time but have ordered it. When I receive it, I will send one to all affected pre-orderers. In the meantime, you can nip the wings of one of the extra adapters and use that. It will do the trick for a while.

[ScreamingAtTheRadio]

Here's what I had in mind the next revision of the FFC adapter:

The idea here is to offset the modern FFC connector to the left of the vintage connector, where there's space when using a vintage Atari motherboard. Haven't checked my modern motherboards but I suppose in those cases you can always solder on pin headers and you won't have the clearance issue.

The whole thing is only 11.65mm tall and will be comfortably clear. The shielding may be another thing you may want to work around, but some light cable origami work should be enough.

So this moves the FFC further to the left of its partner at the back of the keyboard, but nothing that a longer cable can't accommodate. Also, I'm planning on also moving the connector on future revisions of the keyboard. I'll probably actually move it to the top of the board, because that will enable me to have the connectors mounted by the fab house, being on the same side as other components they already assemble. JLC  now stocks a 1mm 26 pin connector similar to the Molex ones I've been using so far.

In other JLC news, JLC now does flexible PCBs that are more affordable than PCBWay, but still pretty expensive: they start at $25. Add shipping and that still makes for a pretty expensive cable, even considering you wouldn't need an adapter.

[ScreamingAtTheRadio]

Finally updated that readme and merged the branch: https://github.com/bleroy/3d-junkyard/tree/main/Atari130MX

[XL Freak]

On 3/31/2023 at 11:44 PM, ScreamingAtTheRadio said:

Here's what I had in mind the next revision of the FFC adapter:

great idea! but as thin as the adapter is, are you concerned it might break in the middle?

 

On 3/31/2023 at 11:44 PM, ScreamingAtTheRadio said:

I'll probably actually move it to the top of the board, because that will enable me to have the connectors mounted by the fab house

sweet! as my vision and lack of experience and proper equipment wont let me solder these on, I paid $14 each at a local phone repair shop to have each connector soldered, one to the pcb and another on the adapter. not bad for a single keyboard, but pricey after that

[ScreamingAtTheRadio]

2 hours ago, XL Freak said:

great idea! but as thin as the adapter is, are you concerned it might break in the middle?

Yes, I had the same concern, I guess we'll see when the PCBs arrive. Folks will have to handle with care. Then again those are pretty cheap to make, and those are the mechanical constraints we're dealing with...

 

2 hours ago, XL Freak said:

as my vision and lack of experience and proper equipment wont let me solder these on, I paid $14 each at a local phone repair shop to have each connector soldered, one to the pcb and another on the adapter. not bad for a single keyboard, but pricey after that

So the quote I got from JLCPCB for the adapters make it not worth having them assemble them, so I'll continue to solder the adapters by hand. That's fine, I've done dozens of those now and I'm getting pretty good at them. I'm also getting a stencil so that I can do them with hot air fast and clean in the future.

For the keyboard PCBs it's going to be a pure win. I'm also replacing the power LED with surface mount, because why the f@#$ didn't I do that before, it makes no sense not to. So we'll only have stabilizers and switches to do manually.

[Dysphoria]

3 hours ago, ScreamingAtTheRadio said:

those are the mechanical constraints we're dealing with...

Would it be better to desolder the connector on the motherboard and replace it with pin headers?

[ScreamingAtTheRadio]

1 hour ago, Dysphoria said:

Would it be better to desolder the connector on the motherboard and replace it with pin headers?

If you're willing to do that, then yes, that's optimal in my opinion (and what I recommend in the readme). This adapter and previous revisions support both. If you're not willing to do desoldering work on a decades old PCB and prefer a plug and play solution, this adapter will work better than previous ones. There's always potential for damage every time you desolder something.

[+Stephen]

Got my kit in today and already have the keyboard fully assembled.  You can follow my progress here - https://www.flickr.com/photos/75619516@N06/albums/72177720307232662

 

[braincell1973]

https://youtu.be/YXdyBjnNeOw

 

A built one in the wild

[kenames99]

I tried to install into 1 of my 130XE computers but had a bad connector on the motherboard. I put it into another 130XE and it worked perfectly and looks a dream! thank you ScreamingAtTheRadio.

 

Ken

 

[Dysphoria]

On 4/3/2023 at 10:20 PM, Stephen said:

Got my kit in today and already have the keyboard fully assembled.  You can follow my progress here - https://www.flickr.com/photos/75619516@N06/albums/72177720307232662

 

Pins 19 and 20 on your FFC connector (last photo) appear bridged.

[_The Doctor__]

Nah it's just flux shine, no bridge. It'll clean up fine.

[+Stephen]

6 hours ago, Dysphoria said:

Pins 19 and 20 on your FFC connector (last photo) appear bridged.

 

6 hours ago, _The Doctor__ said:

Nah it's just flux shine, no bridge. It'll clean up fine.

Yeah - I noticed after I got the photo posted, the flux was not cleaned properly.  I always double check everything under magnifying glass before powering on.  I'll make sure to update that photo when it's all done.

[flashjazzcat]

Jesse has very kindly sent me one of these keyboards (with Falcon-style key caps) in kit form which I'm very much looking forward to assembling (I might video it, if that would be of interest).

[+MrFish]

52 minutes ago, flashjazzcat said:

(I might video it, if that would be of interest).

Do it!

 

[flashjazzcat]

Just now, MrFish said:

Do it!

Will do. Jesse (for whom I previously made a 3.5" 'SF551' disk drive which dramatically went missing in the postal system for seven weeks before finally appearing at his house after I lodged a claim with Royal Mail) really has been generous to a fault, and when I remarked on how nice the keyboard is in the 130XE he sent me for upgrades (turns out it's an original keyboard with upgraded 'rubber cups', but is in excellent shape), he told me to keep that as well (since he'll be replacing it with one of the aftermarket ones under discussion).

 

Thank you Jesse!

[XL Freak]

2 minutes ago, flashjazzcat said:

Thank you Jesse!

you're very welcome! we all need each other 😃

Edited April 6, 2023 by XL Freak

[+MrFish]

With this new keyboard and the 130XE Motherboard Remake, the XE's are having a renaissance.

 

BTW, is there a version of this being produced for the XEGS keyboard?

 

[ScreamingAtTheRadio]

6 hours ago, MrFish said:

BTW, is there a version of this being produced for the XEGS keyboard?

There's been some discussion of this a little earlier in the thread. It should just work, those are the same keyboards, pretty much, and the case has better clearance than the 65/130XE case. You'd just need to make sure you use low-pro switches and adapters for the function keys.

I would love to see it done in fact. Photos of a completed replacement would be very nice to see.

[+MrFish]

4 hours ago, ScreamingAtTheRadio said:

There's been some discussion of this a little earlier in the thread. It should just work, those are the same keyboards, pretty much, and the case has better clearance than the 65/130XE case. You'd just need to make sure you use low-pro switches and adapters for the function keys.

I would love to see it done in fact. Photos of a completed replacement would be very nice to see.

Yeah, I thought that was the case -- minus the function keys (wasn't sure if they'd be an issue).

 

I don't own one currently (used to own several); but I do still own one XEGS base unit; so I might end up getting a keyboard again (if prices aren't murderous in the future). It might be a good project to design a printable XEGS keyboard case...

 

[kenames99]

or you could use one of mytek's keyboard adapters. Transkey II with a ps2 kbd.

[+MrFish]

55 minutes ago, kenames99 said:

or you could use one of mytek's keyboard adapters. Transkey II with a ps2 kbd.

Yeah, it's a worthwhile option to consider.

 

[+Stephen]

Finally - here it is!  My original xmas 1988 present, getting another fine upgrade.  Full album is here - https://www.flickr.com/photos/75619516@N06/albums/72177720307232662 I have some ideas for the function keys.