Terminal Model F : Single-Row Enter Spring Swap.

[sethstorm]

In wanting to switch my Model F over to a Model M(US) style Enter, this is what I did.  

Tools needed:

[*]Needle-Nose Pliers
[*]Large (e.g. the kind used for PC's) Flat-tip screwdriver
[*]7/32 & 9/32 Nutdrivers (for case and keyboard tray respectively)
[*]Backslash & enter keys from a Model M or M13.
[*]White "Placeholder" from another Model M.  
[*]A ton of patience.
[/LIST]

Steps:

1: Separate the keyboard from the bottom tray, disconnecting all cables.

2: Remove all keytops and save them for later.  If you do not do this, you will NOT be able to properly reposition the backing plate.

3: Carefully pry out(away from backing plate) the metal tabs on the top plate from the backing plate with a flat-tip screwdriver.

4: Carefully remove backing plate from top plate by sliding it to the right.  Remember that the backing plate is a curved circuit board.  Take all precautions to not damage it at all times.

5: Put the upside down keyboard between two identical objects so that the springs do not get pushed out.  
5a: If any springs are out of place, make sure that you put them back into place.  Hammers & springs are not the most common objects around.

6: Where your ISO enter key was, swap the spring + hammer that was the immediate left of it, then put it up above, where "\"(backslash) will be.
6a: Re-check that all hammers + springs are in their correct position!

7: Carefully replace backing plate from top plate, lining up all hooks.  Then slide to left.

8: Make sure all tabs are at the correct positions(such that it will not fall out).  Both plates should be held together with a similar force.

9: Place board back onto bottom plate, reconnect all cables.

10: Replace all keys, adding the Enter key + its placeholder as well as the new Backspace key above it.  Without being remapped, it will return a scancode of 0x75.  To Windows, this is unprintable.

11: Connect and check all wire connections.  Plug into computer, and remap the backslash key.

The "International Mod" applies to Model F's as well!

Pictures:


At step 5.  Upside down, looking at hammers.



Close-up of swap in question (see center-right part of photo.  I have already done the hammer+spring swap.  Note the gap that is to the left of Enter and the hammer now present in the Backspace area.



The board.  It should look familiar to Model F owners.



You can put the keys on before or after it is in the case, I put them on before.



Finished!

[sethstorm]

If the pictures won't autoresize, I'll do it manually.  Those pictures should be resizing.

[Superfluous Parentheses]

Nice!

I just noticed that the terminal boards actually do have alt keys in the right place. With this mod that would give it an almost completely sane layout (except for the arrow keys). Very interesting, and I don't know why IBM didn't use a similar layout for the XT/AT variants.

[sethstorm]

Nice!

I just noticed that the terminal boards actually do have alt keys in the right place. With this mod that would give it an almost completely sane layout (except for the arrow keys). Very interesting, and I don't know why IBM didn't use a similar layout for the XT/AT variants.

That, and if those extra pads (left of space bar, right of space bar, and around the arrow/rule home cluster) are usable, you can make it a 127 key keyboard.  You could do inverted T if you didn't mind drilling the holes and cutting out the top case while adding the required barrels, springs, and hammers.  The space bar might have to be replaced with a shorter one, but there look like to be extra usable keys.  All in all, it's not bad for being the only board that's unable to do controller swaps at this time.

[HaaTa]

Looking at the circuit design, I find it strange that there are pads that are not connected at all.
Namely, between the Alts on the left, and to the left and right of the Up and Down arrows.
Notice that there is no power input (dunno what it actually is, but that works) for those pads, while all of the others have them.
I can't see from the picture if they are connected on the other side of the circuit.

Is there any Terminal Board that actually uses a layout with those keys. Otherwise, that'd be a pretty big waste...

The left and right of the spacebar look usable though. But if like the AT, they'll take some work to actually put a key there.

[JohnElliott]

Those extra pads are weird. Firstly they don't seem (from the picture) to be connected, and secondly there aren't any gaps in the scancodes for them. I suppose you didn't try testing them while you had the circuit board out to see if they were detected?

You should be able to get 127 keys even without the pads, by splitting backspace, return, numpad enter, numpad 0 and right shift.

[sethstorm]

Those extra pads are weird. Firstly they don't seem (from the picture) to be connected, and secondly there aren't any gaps in the scancodes for them. I suppose you didn't try testing them while you had the circuit board out to see if they were detected?

You should be able to get 127 keys even without the pads, by splitting backspace, return, numpad enter, numpad 0 and right shift.

Unfortunately not.  At the time, I was more concerned about keeping the hammers & springs from falling out.  Any time you open it, you have to remove every single key for it to properly re-close.  

While there were guides for regular Model F's, I found them a bit lacking in the "how to open the backing-plate up" department.

What would really be nice is if the blue cubes translated more codes.  Aside from the hassles of closing the case, F's appear to be easier to work with than rivet-bound M's.

[Hak Foo]

What does the new backslash do before you remap?

[sethstorm]

What does the new backslash do before you remap?

It responds as a scancode, but nothing is printed.

That key is mapped to a scancode of 0x75 hex.

Needs more keys. 160?

Get a terminal board and some sort of NKRO SPOS board.

[JohnElliott]

A while back, I wrote:

Those extra pads are weird. Firstly they don't seem (from the picture) to be connected, and secondly there aren't any gaps in the scancodes for them. I suppose you didn't try testing them while you had the circuit board out to see if they were detected?

I've now done this with a 6110344 and they aren't. At least, the one in the Left-Windows position and the four round the cursor keys aren't; the ones under Backspace and Return and Right-Shift and Keypad-0 and Keypad-Enter all work fine.

And now I've been spending the last four hours trying to put the back and front halves of the keyboard together, and getting nowhere. First time round I reassembled the whole keyboard but it just emitted a stream of FF bytes (probably a mis-seated hammer somewhere). Second time I got half the keys back on before the front and back parted company. I nearly produced a stream of FF bytes, too.

[JBert]

Wait, did you fail to slide them together until they locked or what? I thought those plates had a quite decent locking mechanism.

[JohnElliott]

Wait, did you fail to slide them together until they locked or what? I thought those plates had a quite decent locking mechanism.

I'd bent the outer sets of clips outward with pliers, and bent them back afterwards. It didn't work: they don't go all the way back once the two halves are together.

I've got the board reassembled now, though. Half-a-dozen C-clamps to keep the plates in the right place relative to each other and a great big trigger clamp to slide them together. Pliers and bare hands just aren't up to the job :smile: