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Do you know where to find this Keyboard? Pics

atod

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I'm restoring a Lear Siegler ADM-3A terminal. The CRT was leaking a brown sticky goo for many years (likely from the polyvinyl adhesive) down into the keyboard. As a result, all the solder terminals at the bottom of the keyboard corroded off. I tried using a Dremel drill and Xacto knife to dig around them so I could solder new ones, however ended up breaking the spring inside the key press assembly.

Does anyone know where or whom may have a replacement for this keyboard? I have all the keys, I just need the assembly. I'm scared that it may not exist anymore. Alternatively, a keyboard with similar style mechanics so I can "cut out" the key-press assembly as a square and join it into this keyboard (where I broke the assembly).

Hopefully I can find a way to fix this or this terminal may become trash.

Thanks !

(Pics follow)

photo1vhv.jpg

photo2dr.jpg

photo3nk.jpg
 

luckybob

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I don't know about a direct replacement, but the keyboard from a TI 99/4a looks like it uses the same style switches.
 

atod

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I checked Ebay Vintage Computer section for keyboards. I didn't see any direct matches. There was an Atari 800 or C64 Vic one that looked similar, however I can't see the key design in the listing. The Heathkit H-89 also looked similar but had an extra row at the top. If the exact replacement is unavailable, I'm thinking I'm going to have to modify some other style keyboard that at least has the keys in the correct places. I.e. cut a numerical keypad portion off...
 

atod

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I don't know about a direct replacement, but the keyboard from a TI 99/4a looks like it uses the same style switches.

Thanks. Do you have a picture of the switches? I did an image search and couldn't find anything showing the keys removed from the switches. Just want to make sure. If the switches are the same, I guess I could cut a few out and move them over to my keyboard.
 

Chuck(G)

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You may want to search around for 70's-era terminals. LSI wasn't the only one that style, but you're not going to find too many on old computers, mostly terminals.
 

atod

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You may want to search around for 70's-era terminals. LSI wasn't the only one that style, but you're not going to find too many on old computers, mostly terminals.

Thanks. I found a couple on Ebay, however am unsure if the keyboard switch mechanism is the same as above pics. If someone can provide actual suggestions based on their equipment (or previously used equipment) that is even more helpful.

Like the TI keyboard, I could purchase that cheap, but I'm not sure about the switch mechanism.
 

Mr.Amiga500

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I don't know about a direct replacement, but the keyboard from a TI 99/4a looks like it uses the same style switches.

No, you're wrong. The TI-99/4a has an Alps style switch.

attachment.php


The keyboard atod is looking for has DEC-style switches. (photo of my DEC VT-100)

attachment.php
 

atod

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I sold my VT-100 within the past year! Does anyone have a VT-100 keyboards they are willing to sell?
 

atod

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Actually, I just found one for $30 + S&H. I guess it could be pulled apart and hacked up to work. I would think the base assembly would need to be sawed to the correct size of the LSI ADM-3A. Leaving only the keys LSI used. I think all the keyswitch positions are identical between the two right?

screenshot20110623at113.png


Here is what the ADM-3A looks like:

LSI_ADM3A_21818_keyboard.jpg


Any comments appreciated
 
Last edited:

RetroHacker_

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A DecWriter keyboard also uses the same style of switches. I *think* the DecWriter/VT100 keyboards were individual switches though. I'll check when I get home. You can also pull the key plungers out and replace the individual contacts, IIRC.

There were many terminals from this era that use the same type of key plungers. I know the Atari 800 does - I've subbed keys from an 800 onto a VT100 before.

That CIT keyboard you picture will NOT work, however. They used a totally different key switch mechanism, despite the housing looking identical to a VT100 keyboard. It's also electrically incompatible with a VT100 terminal...

-Ian
 

atod

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A DecWriter keyboard also uses the same style of switches. I *think* the DecWriter/VT100 keyboards were individual switches though. I'll check when I get home. You can also pull the key plungers out and replace the individual contacts, IIRC.

There were many terminals from this era that use the same type of key plungers. I know the Atari 800 does - I've subbed keys from an 800 onto a VT100 before.

That CIT keyboard you picture will NOT work, however. They used a totally different key switch mechanism, despite the housing looking identical to a VT100 keyboard. It's also electrically incompatible with a VT100 terminal...

-Ian

Ok, I may check out the Atari 800 keyboard. I'm thinking of getting a "hole saw" drill and cutting out the switch assemblies and transporting from one keyboard to the other. Then using MEK or equivalent solvent to weld the piece in.

How do you pull out the plunger? I tried pulling one out from the top (looking down at the keys) and it started snapping around the square housing!

Thanks
 

Mr.Amiga500

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There were many terminals from this era that use the same type of key plungers. I know the Atari 800 does - I've subbed keys from an 800 onto a VT100 before.

Really? That sounds a bit strange. I don't have an Atari 800, but I have a 1200XL (Mitsumi switches) and two different 800XLs (Mitsumi, Alps) and the switches are nothing like the DEC switches. I assumed the 800 used switches similar to the 1200XL.

Here's a link to a brand new Atari 800 keyboard with some info. (no photo of the key switch though)
 

RetroHacker_

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Really? That sounds a bit strange. I don't have an Atari 800, but I have a 1200XL (Mitsumi switches) and two different 800XLs (Mitsumi, Alps) and the switches are nothing like the DEC switches. I assumed the 800 used switches similar to the 1200XL.

800, not 800XL. The two computers are built very differently. The 800XL has more modern switches, but the original 800 has the square plunger/exposed contact type. The keytops are interchangable between the 800 and the VT100.

Lots of other terminals from the era used them too. The Hazeltine 1500 is another one that comes to mind.

When I was fixing the Hazeltine, I had to pull out a fair number of plungers to fix things - I just grabbed them with smooth, narrow nose pliers and pulled them straight out. But the Hazeltine plungers were white - not black like on the LSI keyboard. Perhaps they're put together differently? I didn't have any trouble pulling them out.

-Ian
 

Mr.Amiga500

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Yes, I know the 800 and XL series were built differently, but from what I have read and seen I thought they used similar switches. I'm surprised that they're different. Now I want to find an Atari 800 and test the keyboard feel.

Do you still have that 800? Can you take a picture of the switch?
 

atod

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Really? That sounds a bit strange. I don't have an Atari 800, but I have a 1200XL (Mitsumi switches) and two different 800XLs (Mitsumi, Alps) and the switches are nothing like the DEC switches. I assumed the 800 used switches similar to the 1200XL.

Here's a link to a brand new Atari 800 keyboard with some info. (no photo of the key switch though)

I emailed the seller and he hasn't responded. Does anyone know if these "Rev 3 Stackpole keyboards compatible with 800s made after 1980" have the DEC keyboard design?

I found a 1/4" and 5/8" hole saw and my plan is to cut out and transport the switch as required. Then use solvent to weld the plastic together (or epoxy).

Thanks
 

luckybob

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No, you're wrong. The TI-99/4a has an Alps style switch.

The keyboard atod is looking for has DEC-style switches. (photo of my DEC VT-100)

No... i'm certain my switches look different... I'm going to pull mine out and take a picture.
 
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