[Wiki] IBM 6247440 for RT and 5086 Processor - Rubber dome

snuci · 25 Apr 2017, 03:20

Engicoder was kind enough to send me this keyboard for my IBM RT but I haven't been able to locate the specialized cable to connect it so this keyboard remains in pristine condition in it's box. It really is one of the nicest keyboards I've seen and am very impressed by the look. It is a rubber dome keyboard and differs from the [wiki]IBM RT E57888[/wiki] keyboard which is actually the IBM 6298329 model keyboard. It appears to be made by Brother. Here is a preview of pictures. More pictures are in the wiki at the [wiki]IBM 6247440 for RT and 5086 Processor[/wiki] page.

taylorswiftttttt · 25 Apr 2017, 07:03

removed

seebart · 25 Apr 2017, 14:00

Very nice, love the secondary green and blue legends. I guess it's time to move the IBM RT E57888 wiki page then.

Stabilized · 25 Apr 2017, 14:22

What a good looking board, shame about it being rubber dome. Just a quick couple of questions: are the legends dye-sublimated and what's the profile like? It looks pretty low profile from the pictures, almost Topre like!

seebart · 25 Apr 2017, 15:32

Stabilized wrote: What a good looking board, shame about it being rubber dome. Just a quick couple of questions: are the legends dye-sublimated and what's the profile like? It looks pretty low profile from the pictures, almost Topre like!

Good question, HaaTa said the IBM RT E57888 / IBM 6298329 has dye-subs in his original thread, slightly different keyboard of course!

photos-f62/ibm-rt-e57888-t4101.html

wiki/IBM_6298329

micrex22 · 25 Apr 2017, 15:34

Snuci, you could always create your own cable. Matching the pinout shouldn't be too difficult.

Stabilized wrote: What a good looking board, shame about it being rubber dome. Just a quick couple of questions: are the legends dye-sublimated and what's the profile like? It looks pretty low profile from the pictures, almost Topre like!

Yeah they're dyesub (brother's dyesub machines were less accurate that IBM's from the looks of it, fair amount of bleeding).

seebart · 25 Apr 2017, 15:35

micrex22 wrote: Snuci, you could always create your own cable. Matching the pinout shouldn't be too difficult.

Stabilized wrote: What a good looking board, shame about it being rubber dome. Just a quick couple of questions: are the legends dye-sublimated and what's the profile like? It looks pretty low profile from the pictures, almost Topre like!
Yeah they're dyesub (brother's dyesub machines were less accurate that IBM's from the looks of it, fair amount of bleeding).

Have a look at that keyboard I linked please micrex22 and tell me if you think that might be manufactured by brother also?

dokyun · 25 Apr 2017, 21:04

Real lovely, clean design. This would've made an excellent BS successor to the Model M as opposed to the M2.

micrex22 · 25 Apr 2017, 22:12

seebart wrote:
micrex22 wrote: Snuci, you could always create your own cable. Matching the pinout shouldn't be too difficult.

Stabilized wrote: What a good looking board, shame about it being rubber dome. Just a quick couple of questions: are the legends dye-sublimated and what's the profile like? It looks pretty low profile from the pictures, almost Topre like!
Yeah they're dyesub (brother's dyesub machines were less accurate that IBM's from the looks of it, fair amount of bleeding).
Have a look at that keyboard I linked please micrex22 and tell me if you think that might be manufactured by brother also?

Yeah the earlier RT keyboard Haata has (which he calls a prototopre) has a very similar keycap design to the Brother GX8250, in fact they look identical:

So I'd wager IBM got Brother to make it all (as to why, probably because they just wanted a proprietary 3rd party to make them rather than waste the R&D, or IBM Japan had some dealings with Brother in conjunction with the RT series).

What's funny is that I bet you could do a keycap swap with a Brother GX8250 and early series RT keyboard

Someone may want to investigate Brother's earlier dealing of keyboards to see if they made any PC compatible ones with their same "proto-topre" switches.

seebart · 25 Apr 2017, 22:24

micrex22 wrote: Yeah the earlier RT keyboard Haata has (which he calls a prototopre) has a very similar keycap design to the Brother GX8250, in fact they look identical;

So I'd wager IBM got Brother to make it all (as to why, probably because they just wanted a proprietary 3rd party to make them rather than waste the R&D, or IBM Japan had some dealings with Brother in conjunction with the RT series).

What's funny is that I bet you could do a keycap swap with a Brother GX8250 and early series RT keyboard

Someone may want to investigate Brother's earlier dealing of keyboards to see if they made any PC compatible ones with their same "proto-topre" switches.

Right that's what I think now also. I've been looking at some links and it seems IBM's RT PC (RISC Technology Personal Computer) platform was not as obscure as I originally thought, I found several good links. Just for a blast check out this sales pitch from 1986:

https://en.wikipedia.org/wiki/IBM_6150_RT

http://www-03.ibm.com/ibm/history/ibm10 ... cons/risc/

: us__en_us__ibm100__risc_architecture__rtpc__620x350.jpg (44 KiB) Viewed 3829 times

Daniel Beardsmore · 25 Apr 2017, 22:52

That keycap mount was also used by Mitsumi and maybe other OEMs, particularly in calculators. Generally as usual no-one takes a proper set of photos so we don't find out who the OEM is.

These are the momentary switches in the family used for the Commodore 64 caps lock key:

: mits.jpg (295.19 KiB) Viewed 3826 times

The C64C used a standard solder terminal keyboard switch, but this is the older type with the contacts built around a small PCB as used in the original C64. Oddly, this switch is quite tactile even though the design seems to be linear — the proto-Alps actuator leaf seems to impart tactility.

snuci · 26 Apr 2017, 02:01

Stabilized wrote: What a good looking board, shame about it being rubber dome. Just a quick couple of questions: are the legends dye-sublimated and what's the profile like? It looks pretty low profile from the pictures, almost Topre like!

These might help answer this.

EDIT: This appears the be Brothers Dye Sublimation patent if I read this correctly: https://www.google.com/patents/US4516978

EDIT2: Brothers pad printing patent too? https://www.google.com/patents/US4656078

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: IMG_2159 - small.JPG (270.37 KiB) Viewed 3819 times

snuci · 26 Apr 2017, 02:14

seebart wrote: Have a look at that keyboard I linked please micrex22 and tell me if you think that might be manufactured by brother also?

Brother does have a patent for capacitive key switches here: https://www.google.com/patents/US4736076 Nothing looks exactly like the "protoTopre" switches but you can see a similar "nipple" on top of the patent key switch in Figure 12 of the patent.

On Haata's Flicker pics for that keyboard here he entitled it " IBM RT E57888 6298389 Prototopre Switches (Brother?)".

I'd say it's Brother as well.

EDIT: On further research, our very own [wiki]Keyboard patents[/wiki] Wiki page has entries by Haata on the patent I mentioned. His comment states "Image 7 might be an indication that the IBM RT domes were designed by Brother".