This is yet another Apple keyboard project, with the primary mission objective to be a good, affordable, nice looking keyboard for the Apple-1 which can be built by hobbyists. But there is a reason to put this into the Apple II forum, too:
A secondary - potential - application for it is replacement of decrepit keyboards in vintage Apple II computers. But although I made every mechanical design effort to - hopefully - make it fit into an Apple II shell, I could not verify whether this is true of not, as I long ago have sold the last empty Apple II shell / enclosure I had.
BETA TESTER(S) WANTED !
This is why I post this here in the Apple II forum. Maybe somebody who has both an Apple II and an Apple-1 wants to give YAAK a try. If it does not fit into the Apple II, you still can use it for the Apple-1 . . . and no money nor efforts wasted.
COMPATIBLE WITH THE ORIGINAL KEYBOARD ENCODER ? (NOT YET TESTED !)
Electrically, YAAK should be the same as the original Apple II and II+ keyboard with the separate keyboard encoder card with the 25 pin interconnect to the keyboard. Unless the on-board scanner components of YAAK are populated - then you lose that compatibility.
Theoretically, YAAK without its own scanner components being populated but the 25 connector being added should be able to accept an original Apple II keyboard encoder card and work. It has been my experience that even for the most rotten original Apple II keyboards, hopeless cases of all too many bad keyswitches, their encoder card still works fine more often than not, unless it was ruined by somebody who plugged in the 16 pin keyboard cable in the wrong way.
So there should be plenty of original encoders out there which can be re-used for YAAK. And then, there are replacement encoders based on common MCUs which I heard of, but don't own any of those, so I can't vouch for them.
TESTS STILL NECESSARY
I was not able to test this use case (with the original encoder card) as I did not order the Hirose connector yet, which - hopefully - would accept the pin row of the original encoder card.
UNAVOIDABLE MECHANICAL DIFFERENCES
The YAAK keyboard uses Cherry MX key switches and key caps custom made by Signature Plastics here in the USA. Using these components lead to some mechanical differences to the original keyboards. The biggest issue is with the position of the key caps:
The key caps I found on the first of the two original Apple II keyboard specimen I own are shaped such that they make a concave contour for the fingers - in other words, their tops are not in one plane. This was accomplished by shaping these original key caps in a peculiar way, each row being different, and by adding small plastic interposers between the key switch and the key cap. This contraptions do not fit on the Cherry MX key switches (I tried).
The second original Apple II keyboard I own has key caps which are all shaped alike, and hence would be in a plane, but again, small plastic interposers were added to tilt them a little bit. Presumably, this was done to compensate for the slanted shape of the Apple II shell, such that the key cap tops are parallel to the the desk surface despite of the wedge shaped shell. These plastic interposers also do not fit to the Cherry MX key switches.
So sorry, the original key caps of these Apple II keyboards can't be re-used for the YAAK project, and the newly made key caps will be in the same plane as the keyboard area of the original Apple II shell. Whether this looks acceptable and works for fast touch typists is the still open question.
The only remedy would be to make (3D print ?) small interposers which fit to the Cherry MX key switches, but this is not in my field of expertise, as I don't have a 3D printer. So I don't know if these can make such tiny parts with the required tolerances. Making a custom injection molding form would be prohibitively expensive.So we must accept the limitations of what hobbyists can do and what they can't do.
There is another small difference: the distance from the plane of the key cap tops to the plane of the mounting frame is slightly larger for YAAK, so to arrive at the same height of the key kap tops over the Apple II shell outer surface, added spacer discs may be needed. Having no empty Apple II shell anymore, I can't test this.
Here is a photo showing the different height above the keycap plane:
Also, the YAAK keyboard PCB is designed to be slightly wider in the Y direction than the original PCB, but the original encoder card specimen I have also stick out a bit over the PCB edge of the original, so I designed the YAAK PCB not to exceed that limit. This hopefully is no problem, but no guarantees until it's tried out.
If necessary, the PCB outline could be changed to reduce this dimension, but then the alternate mounting holes which are meant for Apple-1 applications of this PCB will be weakened and might get fatigue failures after a certain number of keystrokes. Still, if the alternate mounting holes are not required, these holes could be removed and the PCB dimension could be reduced accordingly. The idea, for the Apple-1 use case, was to bolt the keyboard to the top or bottom of some custom made enclosure with enough screws that no extra metal reinforcement frame is needed for the keyboard. The original Apple II keyboard only has four screws at the far ends but it does have an integral metal frame. Typical hobbyists can't make such a frame, so I designed in seven (!) extra mounting holes, for screws/bolts with up to 4.8mm outer thread diameter, three on the upper edge, and four on the lower edge of the PCB. Seven of such bolts, strategically placed as they are, should make the keyboard PCB as stiff against bending as if it had a heavy steel sheet metal frame.
All these small mechanical differences might conspire against the use of YAAK in an original Apple II. But this does not affect the primary mission objective, a keyboard for the Apple-1 which in this application looks (almost) the same as the Apple II keyboards which in the past were cannibalized from old Apple II computers. As these old Apple II are becoming sought after collector items on their own right, it's more and more considered a sin to cannibalize them by many members of the scene.
Other than that, at least from the bottom side, the overall size and the mounting holes seem to be a good enough match:
(Never mind the red wire seen on the original PCB, this was needed for tests of the scanner electronics WW lab rat).
WANT TO KNOW MORE ?
Here is the link to the YAAK thread in the Apple-1 forum:
https://www.applefritter.com/content/uncle-bernies-yaak-project-yet-another-apple-keyboard
If you want to help me with testing if YAAK can be used in an original Apple II, please send me a PM. This is the "send PM" button below my user name on the left side. But sorry, I won't send anything to the EU, Norway and Switzerland - their customs procedures and required paperwork got too tricky and time consuming, and even then there is no guarantee they let a parcel pass into the EU. Not worth the hassle and the risks. (And I think it will get worse, as in practice it's looking like a undeclared trade war).
Comments and questions invited - but please, put Apple-1 related comments in the Apple-1 forum thread, and Apple II related comments here in this Apple II forum thread, to avoid confusion of readers.
- Uncle Bernie
Hi fans,
some progress was made with the Apple II version of my YAAK ("Yet Another Apple Keyboard") project.
This morning (yes, a Sunday !) FEDEX delivered a large parcel with electronic components I had ordered from Digikey about mid week. Most are RF stuff for my atomic clock project, but there also was the all important 25 pin Hirose connector (Hirose part # MDF7-25S-2.54DSA(96) , Digikey part # MDF7-25S-2.54DSA(96) -ND).
I had some fears that I might have gotten the mechanical footprint wrong, not badly, and not out of ineptitude to read the Hirose datasheet, but because of the non-negiotiable tolerances on drill diameters at JLCPCB, who manufactured the first YAAK PCB production run. This is a trap any PCB designer must be aware of: once mechanical finished hole tolerance considerations come into play, all bets are off, when you can't walk into the workshop of the manufacturer.
Seems that I was lucky, and the Hirose connector did fit:
YAAK_HIROSE.jpg
And it also smoothly accepts the pins of the original Apple keyboard encoder:
YAAK_w_encoder.jpg
In other words, perfection !
"Perfection" at least for the things which were my greatest worries. There is the minor issue of how to properly fasten the "POWER" key cap to the keyboard (at the moment it's a friction fit of a 3mm LED: the 'cross' in the key cap which normally fastens the key cap to the key stem was drilled up on a drill press using a 7/64" drill bit, which is close to 2.8 mm diameter).
I am not super happy with this solution, but this is the key cap I got with the set of key caps from the manufacturer, and have to live with it, and note that a real illuminated Cherry MX key can't be used, as it would get too high compared to the flat top white plastic cap for the power light on the real Apple II keyboard.
Still, by running a yellow 3mm LED at low current, the outcome looks almost the same, in terms of color, as with the miniature incandescent light bulb that was used on the original APPLE II keyboard:
YAAK_POWER_LED.jpg
A quick functional test on an Apple II clone also showed all keys do work:
YAAK_Test.jpg
The BIIIIG remaining question is whether the whole YAAK keyboard fits mechanically into a real APPLE II shell (of course, I mean those versions of the Apple II which used this style of keyboard, and so the APPLE IIc and the APPLE IIe are excluded).
Any volunteers to try the mechanical fit on their Apple II shell ?
You can get an empty YAAK PCB from me for $6 plus postage, and, alternatively, you can get get this keyboard prototype (excluding the original Apple encoder):
YAAK_AppleII_topview.jpg
. . . for only $95 plus postage (no, you can't buy the components yourself for this money), and if this is too expensive for you, I can take the key caps off and sell you the populated PCB with the original Cherry MX Key switches but without any keycaps for $49 plus postage (only one available, the one I built for these photos, first come, first served !)
Any takers / beta testers / volunteers who want to try it ? If so, send PM to me for more info (sorry, this offer is only valid for people living in the lower 48 of the USA, to keep postage fees at bay).
Return policy:
If it does not fit mechanically into your Apple II shell you can send it back to me (undamaged and in the condition you got it), you pay the return postage, and I will refund you the whole amount you paid, which is the above quoted price, the postage to your home, and the return postage you paid - so you have zero cost if the experiment fails (meaning: it does not fit into the shell).
In this case I would like to know why it did not fit (photos you make), otherwise, no refund ! If the experiment succeeds, meaning: it does fit into the shell, I would like to hear which spacers or other measures you had to add to make it fit. And you should take a photo how it looks from the rear (inside the shell) and from the outside. Also note that you can"t get a refund if you mechanically modify the keyboard in any way (meaning: no cutting, drilling, sawing ...)
These are the rules, which I think are fair.
Sorry to bother you with that call for volunteers. I was stupid enough to sell the last empty Apple II shell I had to a member of Applefritter, many years ago. The reason why was that back then, years ago, I never had the foresight I might need it years later for testing if a keyboard of my own design would fit into it.
Same thing happened to me with some early BYTE magazines (including the issues about the "1977 Trinity", Apple II, PET 2001 and TRS-80) which I threw out after they were flying around in my home for more than 30 years without having been read even once in all these decades. The consequence of this stupid mistake was that I had to buy them again a few years ago, but at outrageous collector's prices. Lesson learned: never, ever, throw away any item that is "vintage computer" related. Never. Just don't do that. All these things are becoming collector's items. They document the start of a new era, the microcomputer era. Which now is about half a Century old (~50 years) and greatly changed our civilization. Imagine what if the microprocessor never had been invented . . .
- Uncle Bernie
That YAAK looks really great! I wish I had any $$$ right now but times are tough. I even have a Videx Enhancer II (replacement for the Apple keyboard encoder board with additional functionality). Maybe you could work with someone like Henry at ReActive Micro to put this into production? He might be willing to pay a small royalty per unit or something or perhaps maybe a one time payment up front. I don't know how he normally works, but he has done similar things for a number of other retrocomputing products like CFFA3k over the years.