Focus Pocus

One of the takeaways from my Time Capsule find was a Focus Electronics FK-5001 – in pristine condition.

This is a photo of it post-cleanup, but amazingly enough there was hardly any dust/dirt/other under the keys.  It was so clean as a matter of fact that I didn’t even bother taking it apart.


Here is a shot of the plate pre-cleanup.  I couldn’t believe how clean it was for its age (it’s from the early 90’s).  Note the fancy Wordperfect 5.1 function key template.


This was not only my introduction to Alps white keyswitches, but to yellows.  The white are clicky, the yellows (for CAPS lock, Scroll lock, and Num lock) are linear.  The yellows buttery smooth, and the whites are very pleasant to type on.  Not quite as crisp and punctuated as Alps blues, but satisfying nonetheless.


This guy comes with a calculator built-in to the keyboard!  Works perfectly.  Some people have indicated to me that the calculators were finicky and failed often, so I guess I got lucky.


It was rather nice not having to fight through seven layers of grime to enjoy this keyboard.

Unfortunately this is another that is sensitive to hot-plugging, so I can’t plug this into a running system and expect it to operate; it has to be booted with the machine.



Finally had a chance to clean up the Triumph FKB4700, find another AT to PS/2 adapter, and semi-permanently hook it up to a machine that is routinely power-cycled.

I still find it quite enjoyable to type on.  I just dig the feel of the keycaps; they just have such a nice non-slick, non-stick “matte” feel about them. They’re different enough that I notice them, and I find that interesting.  I noticed that from before I even purchased the group of them.

These boards don’t get a lot of love, and while I can understand some people’s complaints about them, as far as the typing experience overall I find that it is pleasant.  I’m glad to own one.  I think I’ll just try avoiding the move to that keyboard after typing on something superior immediately prior…


Sniff Sniff

I spent a little more time investigating the VPE-151 and how it communicates to its host.

With a “normal” keyboard, data and clock lines are used to transmit make/break scan codes to the host, and it is responsible for translating them into equivalent ASCII characters or to alter the internal state of CAPS lock, etc.

I cannot find a clock line.  This observation zaps my previous theory that standard PS/2 signals might have been routed to the connectors in back, and the host would operate on those just like a standard keyboard.

vdrrcvThere is a socketed SN75179BP differential driver/receiver chip on the connector plate PCB.  What might it have to tell me?  I hooked up a logic analyzer and sniffed the output.  After capturing a keystroke, I found that it is communicating serially with no parity, 8 data bits, 1 stop bit, idle is low, bit encoding = high is space, LSB first.  Ignore the timing; that is an anomaly of the sampling rate.  It speaks!  Welcome to the letter A.

OLS - VPE-151

The CPU is scanning the keyboard matrix and outputting ASCII for the letters of the keyboard.  Out of curiosity, I checked what was output for some of the other keys.


  • ASMB (where a TAB key normally sits) = decimal 39 (hex $27)
  • RECORD (where CAPS LOCK usually is) = 40 ($28)
  • Left SHIFT = 41 ($29)
  • U4 = 42 ($2A)
  • REV (left CTRL position) = 43 ($2B)
  • FWD (left ALT position) = 93 ($5D)
  • PEGS (tilde position) = 245 ($F5)
  • SLVS (1 key position) = 246 ($F6)
  • OPEN END (2 key position) = 115 ($73)
  • CLR OUT (3 key position) = 116 ($74)
  • SAV MKS (4 key position) = 118 ($76)
  • RETURN key = 13 ($0D) (ASCII carriage return – nice)
  • ENTER key (far right on numeric keypad) = 10 ($0A) (ASCII newline)
  • SPACE = 144 ($90) (not a decimal 32 for an ASCII space? Hmm)

If I wanted to interface this keyboard to a computer, it should be within my abilities to do so.  The next biggest consideration I have is whether or not I would really want to spend the time doing it.  Considering that it is a bit awkward to type on (the RETURN key and U4 key by the SHIFT, etc.) combined with the fact that I do not like typing on Cherry MX blacks and I always have a million other projects… the prospect is not particularly appealing at this time.

That said, I have no plans to part with it at the moment.

Inside the VPE-151


Metal case is 1.75mm thick.  Keyboard weighs 6lbs, 7.7oz.

Had to open it up and take a peek.  I was anxious to:


Sorry for the dirt in the photos; these are pre-cleanup.

vrom vpartno vlabel vkeycap vinsidebottom vinside2 vinside1

I was able to find a datasheet on the NEC uPD8049H; it is an 8-bit microprocessor that can run up to 11MHz.  It has 128 bytes of RAM, 2KB of ROM, 27 I/O lines.  The datasheet pinouts for ground, power, and external crystal match what I observe on the PCB.  It is being run with a 2.4576MHz crystal.vcpu vconnectors vconnector2 vconnector1 vcherryblack


Fitting title, as it describes the keyboard as well as (finally) revealing its finicky behavior.

This is one of three Triumph Systems FKB4700 keyboards that I picked up in the “Time Capsule” transaction (before cleaning).  It weighs 4lbs 5.5oz with its cord.


I had troubles with this board.  It was a rather strange scenario that had my subconscious working harder than it needed to.

The trouble was, it didn’t work.  It has the large-style AT DIN connector, so I used an AT to PS/2 adapter, then a passive PS/2 to USB adapter.  The num lock and scroll lock key LEDs would light up briefly, then turn back off.  At that point, the board was unresponsive.  The other two boards had the same behavior, so I stubbornly refused to believe they were defective.

The next step was to try an active PS/2 to USB converter (a “blue cube”).  Same exact result.

After that, I tried bypassing the USB portion and plugging the board directly into a machine with a PS/2 port.  Same thing.

So, I pulled out a trusty old PC that I’d replaced a failed motherboard in long, long ago, that had an AT-style connector.  Boom!  It worked.micron

My conclusion from this is that there was perhaps too much current draw from the board, and it required more current than the PS/2 or USB ports could deliver, but the old AT-style port in the old PC could.

Just out of curiosity, I snipped the keyboard’s power line and measured the current when the keyboard was on to be 21mA, peaking at around 86mA.  Definitely not a current high enough to cause issues.  I re-soldered the power wire and put heat-shrink on it, and asked questions about its behavior on Deskthority.  There were no concrete answers, but two helpful gentlemen (Muirium and chzel) suggested that the issue might be that the board only talked the XT protocol.  Muirium went on to suggest that the BIOS in the old PC was able to detect it and communicate with the board.  That made sense, and I felt a bit foolish for assuming it was a current problem.

However, that did not ultimately resolve anything as far as actually using it.  If it was indeed an XT-only board, I wouldn’t be able to use it in a modern system without a smart adapter (Soarer’s adapter for instance).  I abandoned it for nearly two months.fkb4700-label

Yesterday morning I’d tossed around ideas of making a simple protocol adapter myself as a learning experience, and even went so far as to observe its clock and data lines on an oscilloscope to determine if it really was attempting to talk via the XT protocol.  It was fun to see it on a scope, but unfortunately when it was powered up with a 5VDC supply, I saw the same behavior – the num and scroll lock LEDs would light up briefly, then go silent.  There were no visible alterations on the data line when a key was pressed; it was if the keyboard was dead.

This morning, I couldn’t stop my brain from making another go at determining whether or not it spoke XT instead of AT, so I started digging up datasheets.  My first thought was checking to see if the BIOS in the old computer supported the XT protocol at all.  It was an Epox P55TV2 motherboard with an 8042 keyboard controller chip.  The motherboard manual nor the 8042 datasheet indicated anything about XT.  The P8051 chip in the keyboard is a general-purpose microcontroller that could have had its EEPROM programmed to support either protocol, so that wasn’t helpful.


So I was back to thinking that it was an AT protocol board (as the Deskthority article on the Fujitsu FKB4700 states), and if current demand wasn’t the issue, what was left?

Then the pieces of the puzzle all fell into place.

It’s how the board is powered up.  There is some kind of initial dialog that I am not aware of that prevents this board from operating if plugged into a running system.  If I power up a machine with this board connected either via PS/2 or through adapters to USB, it will work.  If I unplug it and plug it back in, guess what- the num and scroll lock LEDs light briefly, then the board goes to sleep.  In all of my prior testing, I was powering up the old PC, but with the other adapters, I was testing on already-running systems!  Doh!  So, for some reason it has to be powered up with the machine and never unplugged.  Perhaps it’s an anomaly of the coding in the P8051, I’m not sure (what else would it be?).  I will probably ask on Deskthority to see if others have had this experience with the non-Triumph-branded FKB4700’s; I’ll update this post if I learn something from that.  I definitely learned something new though; I’ve never experienced that behavior before.

Some people do not like these boards at all, with complaints that some of the modifier keys, if pressed off-center, will bind. Indeed, they do have that tendency.  However, from the very first touch of one of these boards, I was immediately attracted to how the keycaps felt – smooth and “dry” – not slick.  I have to say – I like it.  This has the clicky version of the Fujitsu Peerless keyswitches, and while it’s not the best thing I’ve typed on, it is definitely far from the worst.  I’m looking forward to having this in my lineup (now that I know how to properly operate the damn thing!).

I’m not quite sure I know what to do with three of these, but at least I can take this one, start the cleaning procedure, and enjoy it.


fkb4700-bottom case 1 fkb4700-bottom case 2 fkb4700-bottom case 3 fkb4700-controller board fkb4700-id  fkb4700-no top  fkb4700-side fkb4700-top case 1 fkb4700-top case 2 fkb4700-top case 3 fkb4700-under platefkb4700-keyswitch



After watching eBay for months, I did not feel that I had the patience to wait any longer nor would I get a significantly better deal by doing so, so I bit the bullet and reeled in a Model F PC AT board from a seller in California.

The typing experience is significantly more satisfying than a model M (and I do like the M a lot).  The keys feel wonderful and have an awesome snap, ping, and clack.  Compared to the model M, everything is more pronounced.  The layout is a bit too weird for me to use it for anything but straight-up typing, but I knew that going in.  The only real wonky thing that is taking me a little getting used to is the spacebar stabilizer … like, there isn’t one or it’s extremely poor or worn out.  I hadn’t heard of that issue before, but even if I would have known it, I still would have purchased the board.  I just have to remember to keep my thumb fairly centered, and after a bit of practice, it’s actually turning into more of a non-issue.  Absolutely no regrets, and it ranks way up on my list.

She weighs 5lbs 3.5oz and is in excellent condition; just a mild wiping with alcohol and we’re off and running (the picture above is before the wipe-down).  There may be an eventual disassembly for a thorough cleaning, but it’s certainly not required at this point.

Definitely the loudest keyboard I own, and it’s just plain fun to type on.  It is nice to experience this again after more than 30 years.

This does bring about a self-imposed moratorium on my keyboard purchasing habit however.  I’m done even thinking about buying another keyboard (unless it’s one particular board I’ve been hunting for months) until I’m done processing and cleaning up the VPE-151 and the boards I bought in the Time Capsule haul.


Time Capsule Round 1

In my Time Capsule post, I wrote about an abandoned electronics shop that allegedly had hoards of keyboards in it.

Last week I finally made contact with the curator, and he had a chance to pull some of the findings out of the building.  My brother suggested that there was so much stuff stacked in there that this probably only represents “round one.”


These are pretty dirty, and they don’t smell super pleasant – as a matter of fact, they’re making my office smell old and stale.  I believe some will clean up nicely however.  What you see here:

  • EW4KK R4018 (rubber dome?)
  • IBM M2 1395300 (7/20/1993)
  • HP 46020A
  • HP C3346-60201 (rubber dome?)
  • IBM 1391401 (5/19/1987)
  • Triumph FKB4700 (x3)
  • Focus FK-5001
  • Focus FK-2000
  • Leading Edge DC-2014 (blue Alps)
  • IBM 1390120 (1/6/1987)
  • APC-H412 (NEC blue ovals)

While I didn’t find exactly what I was hoping for, there are some interesting keyboards to check out.  The feel of the Triumph boards (clicky and pleasantly smooth) is quite nice and I’m looking forward to cleaning those up.

EDIT 9/2/2015: I finally had to move these keyboards out of my office and into my shop because they stunk like a combination of dust and must and who knows what else.  Also determined that the Triumph boards would not work with a passive USB adapter, active USB adapter, or even a direct PS/2 connection – however they -did- work when connected to a 1998-era computer with a real AT connector.  Odd!