Another new project (IBM PCJr)

tatsurou

04 Dec 2018, 05:20

Henlo again,

I bought this abomination of a keyboard for 10USD since nobody likes them and will try to turn it into something more up to date (different switches maybe?)

Any ideas perhaps? I liked the style of CA66 keyboards to be fair. :D

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tatsurou

04 Dec 2018, 05:45

Calculator electronics:

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PCJr patented breast implant tactile switch:

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All make perfect combination where they belong:

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snacksthecat
✶✶✶✶

04 Dec 2018, 06:17

I like where this is going

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zrrion

04 Dec 2018, 06:35

This is off to a much better start than I was expecting honestly.

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depletedvespene

04 Dec 2018, 12:02

An abomination of a keyboard, indeed. I respect your technical ability for restoration, although I wouldn't bother with this thing.

Anyway, mind if I reuse your picture of the keyboard so I can make a shitpo... a post-mortem analysis of the PCjr's keyboard's layout? :)

tatsurou

04 Dec 2018, 14:44

Yeah, use it whenever you want:)

JBert

04 Dec 2018, 19:08

tatsurou wrote: Calculator electronics:

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The waving quality of those hand-drawn traces on that PCB though... :)

tatsurou

05 Dec 2018, 00:41

yea, it looks very crafty :D

tatsurou

10 Dec 2018, 04:32

Mini update:

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Guts cut out quickly (will be finished):

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Dreaming big:

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tatsurou

10 Dec 2018, 04:57

This board was made using imperial measuring system, but measured it using metric as accurately as possible. Here you go guys, for future reference:

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abrahamstechnology

10 Dec 2018, 05:57

Are you going to handwire the original controller?

tatsurou

11 Dec 2018, 02:22

Plan is pretty simple. Draw a new mounting plate for switches and install them on that. I am considering something from Kailh as they are available, cheap and in general providing a good soundtrack as for modern switches. I won't be building a pcb for it as I don't want to spend too much on this thing. And later, I will reuse some controller from a different board. That is the most reasonable idea in my opinion. Do you guys have any switch or technique recommendations?

tatsurou

13 Dec 2018, 00:36

Quick imagination of what will happen:

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abrahamstechnology

13 Dec 2018, 01:03

Recommend SMK MX mount switches, works with Cherry plates and caps with Alps-like click leaf. There's some on TaoBao for pretty cheap.

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depletedvespene

14 Dec 2018, 15:28

abrahamstechnology wrote: Recommend SMK MX mount switches, works with Cherry plates and caps with Alps-like click leaf. There's some on TaoBao for pretty cheap.
Ok, I can't take this anymore. Generally speaking, I don't like to chop off parts of a keyboard or do major modifications to it that aren't really needed, but in this case... this being a PCJr keyboard to begin with, I'll say that THAT growth on the case should be sawed off and the freed space be used with an actual key.
Gaaaaaaaaaaaaah. Chop this off!!! (YMMV)
Gaaaaaaaaaaaaah. Chop this off!!! (YMMV)
sawbabysaw.png (208.77 KiB) Viewed 9990 times

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zrrion

14 Dec 2018, 19:42

Look, he's already using a board most people wouldn't even look at, he might as well embrace the quirks of the layout.

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depletedvespene

14 Dec 2018, 20:11

The lower left side we can call a quirk (YMMV); the \gap, OTOH, is just a design defect (YMMNV).

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abrahamstechnology

21 Jan 2019, 17:48

Any updates?

Sturmtiger001

04 Apr 2020, 09:07

Wonder if this thing went anywhere, seems like a neat idea to say the least.

trtr-dmdm

17 Oct 2020, 04:38

Reviving this thread...

Working on rebuilding PCjr keyboard on my own. Come here for layout advice.

Here is original layout: http://www.keyboard-layout-editor.com/# ... 7d9c443fdc

Here are few layouts I'm considering, any ideas what may work best? Any other creative ideas?

"Chopped" http://www.keyboard-layout-editor.com/# ... 2290a82fda
"Standard keys only" http://www.keyboard-layout-editor.com/# ... 23c36e7ac4
"ISO Enter" http://www.keyboard-layout-editor.com/# ... d04e13dc65
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ibm-pc-jr---chopped---60%-+-left-row.png
ibm-pc-jr---chopped---60%-+-left-row.png (37.52 KiB) Viewed 8066 times
ibm-pc-jr---standard-keycaps-only.png
ibm-pc-jr---standard-keycaps-only.png (37.07 KiB) Viewed 8066 times
iso-enter-ibm-pc-jr.png
iso-enter-ibm-pc-jr.png (36.81 KiB) Viewed 8066 times
ibm-pc-jr-original.png
ibm-pc-jr-original.png (37.77 KiB) Viewed 8066 times

Excelso

17 Oct 2020, 23:40

The second one seems pretty good for me.

Rayndalf

22 Oct 2020, 19:52

I'd love to see where this is going, I have a PCjr board that I'd love to modify, but I'd also like to find a way to use the original keycaps.

trtr-dmdm

27 Oct 2020, 00:06

@rayndalf I highly doubt original keycaps are reusable. The way Enter and Spacebar mounted is just awful and not reusable.

There were some ideas around adapting keycaps by making inserts for them or inserting smaller MX keycaps into PCjr's.

Progress so far is I have plate working, need to figure out if hand wire or try PCB design next.

download/file.php?mode=view&id=63849
Attachments
Screen Shot 2020-10-26 at 7.05.50 PM.png
Screen Shot 2020-10-26 at 7.05.50 PM.png (1.7 MiB) Viewed 7797 times

kelvinhall05

27 Oct 2020, 13:54

trtr-dmdm wrote:
27 Oct 2020, 00:06
need to figure out if hand wire or try PCB design next.
If you want a Pro Micro based PCB, pm me. I could also do integrated controller but it would be more expensive to produce and you'd have to solder the USB port yourself, if not other components (and I'd charge more for the design lol).

But yeah, nice, fun project! I've thought about doing this myself for a while but haven't found a PCJr keyboard cheap enough to do so :/

xTejima

28 Jan 2021, 17:32

kelvinhall05 wrote:
27 Oct 2020, 13:54
[quote=trtr-dmdm post_id=473445 time=<a href="tel:1603753591">1603753591</a> user_id=20502]
need to figure out if hand wire or try PCB design next.
If you want a Pro Micro based PCB, pm me. I could also do integrated controller but it would be more expensive to produce and you'd have to solder the USB port yourself, if not other components (and I'd charge more for the design lol).

But yeah, nice, fun project! I've thought about doing this myself for a while but haven't found a PCJr keyboard cheap enough to do so :/
[/quote]

I would be interested in a PCB from you for a project similar to the OP’s project

xTejima

28 Jan 2021, 17:34

I apologize, I’m new to this forum and I’m not good at commenting a reply to a comment. I am interested in pcb from you kelvinhall05

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joebeazelman

05 Feb 2021, 01:29

The PCjr is my first computer and I have nothing but fond memories of it. The original chicklet keyboard was truly an abomination, making it a laughing stock of computers even to this day. The later revised rubber dome keyboard discussed here wasn't too bad. It was certainly better than many of its competitors, such as the chronically fatiguing Commodore 64 keyboard.

While it may sound overpriced now, a PCjr with a very high quality RGB monitor could be had for under $1000, making it an incredible deal for a 16-bit machine with 128K of RAM. This was at a time when its competitors shipped 8-bit machines with barely 64K of RAM. Unfortunately, and to no one's surprise, IBM crippled it just enough to keep it from competing with its more lucrative father, the IBM PC. The mere fact they brutally maimed the keyboard demonstrates just how much they understood it as a critical part of a computer's perceived value. In contrast, today's computers ship with the lowest quality keyboard regardless of the price point.

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