PR1ME PT200 keyboard restoration. Help?

[agdurrette]

Looking for info on this keyboard. Hoping someone can give me more info on this company, keyboard and probably the type of switches it uses.
I'm wanting to get this keyboard working but I need to learn first how it works... After some reading I believe it uses either induction or magnetic valve switches.
Right now I have a keyboard looking much better, album of pics http://imgur.com/gallery/u7nu2

[Techno Trousers]

Well, that brings me back. My second job out of college was doing software and database support on a Prime minicomputer. I remember using those PT-200 terminals, but not being overly impressed with the keyboards. I much preferred the SIIG Suntouch keyboard on my home computer (Alps white SCKM switches).

I'd say Prime's main claim to fame was the Prime OS and DB (based on Pick). The way they did their values and subvalues lists in the DB was pretty nice. It was a lot easier to create and maintain an arbitrary list of, say, phone numbers in a list within a table, rather than the relational method of having an entirely separate child table.

Wikipedia has a nice article on the company.

[seebart]

Welcome to DT agdurrette!

That keyboard of yours looks like it may have been part of a Prime PT250 terminal:

Terminal-prime-pt250.jpg (47.4 KiB) Viewed 2288 times

Sorry, I do not know anything about the company or their hardware, with some patience you sould be able to find more than I did just now:

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

http://www.malch.com/prime/

http://www.chilton-computing.org.uk/acd ... erview.htm

[agdurrette]

I remember using those PT-200 terminals, but not being overly impressed with the keyboards.

Yah, it seems like it could uses a good bit of lube, the slider part protrudes out the top a bit and gets bound if you don't push straight down. not something i would like to use everyday...

I'd say Prime's main claim to fame was the Prime OS and DB (based on Pick

Were the computers any good? Looks like they had their 15 minutes and never did anything after that.

That keyboard of yours looks like it may have been part of a Prime PT250 terminal:

First time seeing that photo, Looks like they used the same keyboard with a couple of their computers.

Here is a Prime 9950


I have a PT200 myself,and the keyboard has the same model number as the computer. which is kinda weird, if they used the same keyboard wonder why they labeled them different. :/

with some patience you sould be able to find more

Unfortunately that's all I've really found myself, their os is documented semi well, the company itself has decent info, the wiki gives basic info about the computers (info gotten from the other sits most likely) and the keyboards, nothing on the keyboards...

Interestingly, the inside of the computer has info about the composition of the plastic, company that made the plastic, UL rating, company that made the shell, all kinds of info...

I just found this. keyboards-f2/ncr-k430-magnetic-valve-se ... 11152.html !!!

[Daniel Beardsmore]

Yours seems to have no ADI branding, and it's older than XMIT's. I don't off-hand have any records of the dates of them all, and what PCB branding was found for each date.

[agdurrette]

Its the same type of switch definitely.
Found two other posts different keyboards, same switches. Mine has white stems/sliders.
photos-f62/adi-ki-5170-t6915.html

https://www.reddit.com/r/MechanicalKeyb ... is_switch/

Also to note, there are 3 different switch housings. Housings are numbered 1-3, 1 is normal, 2 and 3 have clips to hold the stabilizer.

[Daniel Beardsmore]

Most of these PCBs have "ADI" silk-screen printed at the top right, suggesting that ADI was the OEM. Yours instead have "PRIME" written on the PCB in copper (covered with solder mask), plus the sliders are inexplicably white instead of black. Yours that you've detailed is from 1985, which appears to make it the oldest. There seems to be some kind of ownership history here. I've not taken the time to study all the dates; that is a good place to start, i.e. see if there's clear evidence that the Prime version is older than the ADI version.

[agdurrette]

That's interesting, also noticed the one that did not have ADI marking had an FCC ID that was for ADI. I'm assume that ADI would have made the switches themselves?

Are you getting 1985 from the SN and the ICs? I have a couple boards one has different ICs and I did not note the SN.

EDIT: would be interesting to get the others on board so we can document the switches/keyboards for the wiki.

[Daniel Beardsmore]

Going solely by the Imgur posts:

One PCB is marked 8542 (week 42 1985)
Another PCB is labelled 851118 (week 47)
The ICs are dated between 1983 (the little Hitachi chip) and 1985

Ownership of tooling can be transferred. This has been seen with Apple switches (the branding was defaced within the mould to remove the Apple logo), ITW/Cortron low-profile magnetic valve switches (Devlin in the UK acquired the tooling), Cherry keycaps (GMK acquired their doubleshot keycap tooling), simplified Alps (Datacomp rebuilt the simplified Alps tooling after it wore out and Forward disposed of it), and nobody's quite certain what went on with the Dell AT101 when Silitek took over manufacture. In China there is apparently tooling sharing, i.e. multiple companies can share access to the same tooling (this is all I know, I don't have any details on this) and that may be an alternative explanation for the rebranding of a specific type of SMK J-M0404 derivative — mine have the branding removed with a rotary tool under CNC control, and the moulds are pretty worn out (photos of them in the past show switches made when the moulds were in good condition). They're the same switch, as the cavity numbers are identical in both instances.

The Imgur pictures give a taster if you like, but they're not precise and comprehensive enough. For example, one PCB is marked "PRIME", but I don't know what exact labels corresponded to that one, and if the other side of that PCB says "ADI" anywhere.

I can't draw any conclusions without having much more detailed information.

[agdurrette]

I will have to see if i can reach out to the other users for more detailed photos.

Here is another album http://imgur.com/a/SPVZz

The front of the PCB has the ICs on it.

The main chip does have what looks to be dated 1997 (http://i.imgur.com/asbFtKp.jpg ) which to me seems to be odd for something that seems to be older than 1997

[Daniel Beardsmore]

I have no idea what the 1997 means. Date codes typically give the week, either in the form YYWW, or (as with the Hitachi chips) YMW, and normally have one or two letters at the start or end. 8527H looks like a date code, and it fits in with all the other dates found everywhere else (IC dates, serial numbers, production labels and PCB dates).