Honeywell 5921 Clean Up and Teensy USB

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OldIsNew

25 Sep 2018, 08:56

I was able to pick up this rather interesting old board. It's from the Honeywell VIP 5921 terminal. I haven't been able to find out too much about it, though it was from the 1970's according to the epocalc computer models database.

It was pretty yellowed and dirty:
HoneyWell_front_orig_small.jpg
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Honeywell_case_back_small.jpg
Honeywell_case_back_small.jpg (139.65 KiB) Viewed 4029 times
Caps off and case removed:
Honeywell5921_caps_off1_small.jpg
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The switches are made by Oak and are ones I haven't see before:
Oak Switch_small.jpg
Oak Switch_small.jpg (235.56 KiB) Viewed 4029 times
switches_angle_1_small.jpg
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switches_side_1_small.jpg
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switches_top_small.jpg
switches_top_small.jpg (351.51 KiB) Viewed 4029 times
The switches would have to be desoldered to remove the face plate, so I didn't do it.

The PCB is interesting, it took a little while to figure out the matrix:
PCB_back_small_2.jpg
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Then wired up the matrix to the Teensy 2.0++ and ran wires to the onboard LEDs:
Teensy_small.jpg
Teensy_small.jpg (254.06 KiB) Viewed 4029 times
LEDs wired_small.jpg
LEDs wired_small.jpg (285.67 KiB) Viewed 4029 times
Cleaned up the case and then Retrobrited the caps and they look a lot better:
After_RetroBrite_small.jpg
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Flashed my firmware and tested, then reassembled everything and up and running:
Honeywell_case_front_small.jpg
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Honeywell_case_rear_small.jpg
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Honeywell 5921 done small.jpg
Honeywell 5921 done small.jpg (218.52 KiB) Viewed 4029 times
The switches are linear, rather smooth and fairly heavy. Not bad overall in my opinion. I made a short video of typing on it:

xxhellfirexx

25 Sep 2018, 19:26

Awesome find! I have never seen a vintage floating key design before.

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Muirium
µ

25 Sep 2018, 19:57

Clear switch bodies too, no less. They were decades ahead of their leet gamer time! Just needs underlighting LEDs in there and maybe an artisan.

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Chyros

25 Sep 2018, 21:14

Wow, what are that?! Oo

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Hypersphere

25 Sep 2018, 22:39

Marvelous! Who said keyboards aren't fun anymore?! You've done a great job figuring out the matrix and converting to USB. And the retrobrite treatment certainly restored the former beauty of the caps. I have yet to try retrobrite -- it looks like a messy procedure, and I understand that it requires sunlight or a sunlamp. I don't own a sunlamp, and sunlight is somewhat scarce in my locale.

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Sangdrax

28 Sep 2018, 06:48

That retrobright turned out fantastic. I can't believe that thing cleaned up so well.

green-squid

28 Sep 2018, 08:01

Oh my gooooood !!!!!!!!! :o

This is super duper cool! I want to get a keyboard like this and convert it soo much!!!

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OldIsNew

29 Sep 2018, 06:27

Thanks for the feedback everyone. It's kinda of a fun old board - and I'm also surprised it cleaned up so well!
Hypersphere wrote: ... I have yet to try retrobrite -- it looks like a messy procedure, and I understand that it requires sunlight or a sunlamp. I don't own a sunlamp, and sunlight is somewhat scarce in my locale.
I've done several sets of keys now with 3% H2O2, a dash of OxiClean and simple clamp lights with good results so far. I posted some pics and a description here: workshop-f7/another-go-at-retrobright-t17393.html . I left my first set unsupervised for about 8 hours and got away with it but I would recommend supervising things closer as it is definitely possible to over bleach things.

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OldIsNew

18 Oct 2018, 04:07

Well I've spent the last week going back and forth with Honeywell, trying to learn something about this keyboard/terminal. I had to set up a Honeywell account (which was not as easy at it sounds) and exchanged email with a number of people, but at least someone at Honeywell did make some effort to look it up and at least sent this:
Honeyell_5921_info2.jpg
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Unfortunately, there are only 76 keys on this board so I suspect it's so old that they don't have any records. Well, I still have to thank them for at least trying to answer a question that certainly isn't going to sell any new product.

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Hypersphere

27 Oct 2018, 16:50

OldIsNew wrote: Thanks for the feedback everyone. It's kinda of a fun old board - and I'm also surprised it cleaned up so well!
Hypersphere wrote: ... I have yet to try retrobrite -- it looks like a messy procedure, and I understand that it requires sunlight or a sunlamp. I don't own a sunlamp, and sunlight is somewhat scarce in my locale.
I've done several sets of keys now with 3% H2O2, a dash of OxiClean and simple clamp lights with good results so far. I posted some pics and a description here: workshop-f7/another-go-at-retrobright-t17393.html . I left my first set unsupervised for about 8 hours and got away with it but I would recommend supervising things closer as it is definitely possible to over bleach things.
Thanks for the link to your workshop post! I had not seen this before. Some questions for you:

1. Which lamps (halogen or black light) were directly overhead (90 degrees to the surface of the bath)?
2. How did you clamp the lamps in place? Was the whole setup on a piece of wood with the clamps on the edge of the wood?
3. Did you try this with halogen only or with black light only? Just wondering if UV is essential for the bleaching process.

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OldIsNew

27 Oct 2018, 22:34

Hypersphere wrote: Thanks for the link to your workshop post! I had not seen this before. Some questions for you:

1. Which lamps (halogen or black light) were directly overhead (90 degrees to the surface of the bath)?
2. How did you clamp the lamps in place? Was the whole setup on a piece of wood with the clamps on the edge of the wood?
3. Did you try this with halogen only or with black light only? Just wondering if UV is essential for the bleaching process.
In that picture the black lights were overhead and the halogen lamps at the sides. Two lamps were attached to a board and two to overhead cabinets. Since then my set up has been ejected from the laundry room and I have been using it elsewhere in the basement (see pic below). I've done four, or I think five now, additional sets of keycaps with good results. Since the set up I have has worked well (and since the keycaps I've done have been vintage and I would be unhappy if I messed them up), I have not experimented further with lights, etc.
retro2.jpg
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That being said, I have doubts that the two 60W CFL blacklights are adding much to the process. I'm not a chemist, but my suspicion is that it the IR EMR from the 90 watt halogen bulbs, which heats the peroxide bath quite a bit, that is primarily responsible for driving the chemical reaction forward. This could also explain observations that sunlight (approximately half of the suns energy that reaches earth is in the IR spectrum) seems to work better that UV lamps - though of course can't be certain since the sun's energy output across the spectrum is so great.

I think experimenting with black light only/ halogen light only , and heated bath in the dark, would be worthwhile. I just don't have any keycaps, or other yellowed plastic I want to experiment with at the moment.

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Hypersphere

28 Oct 2018, 01:23

Thanks for the additional information.

Hydrogen peroxide interacts with photons in the UV to produce hydroxyl free radicals, which are powerful oxidizing agents.

Hydrogen peroxide when heated (e.g., IR energy) breaks down into water and oxygen. Of course, oxygen is also an oxidizing agent, but it is not as potent as hydroxyl radicals.

This would indicate that both of your light sources (IR and UV) are contributing to the bleaching effect, but I think that the UV sources would be having the greater effect.

Even so, it would be good to do some tests. I will try to do so when I can find the time.

In the picture you showed above, what are the materials beneath the lamps? I cannot tell if it is plastic wrap, plastic bags, aluminum foil, or some combination of these. Do you use a glass or plastic container for the hydrogen peroxide solution?

Thanks again.

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lucar

28 Oct 2018, 17:05

Great conversion!!

Luca

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OldIsNew

29 Oct 2018, 01:22

lucar wrote: Great conversion!!
Luca
I am finding it interesting!
Hypersphere wrote: Thanks for the additional information.

Hydrogen peroxide interacts with photons in the UV to produce hydroxyl free radicals, which are powerful oxidizing agents.

Hydrogen peroxide when heated (e.g., IR energy) breaks down into water and oxygen. Of course, oxygen is also an oxidizing agent, but it is not as potent as hydroxyl radicals.

This would indicate that both of your light sources (IR and UV) are contributing to the bleaching effect, but I think that the UV sources would be having the greater effect
Interesting! I used a glass (Pyrex) pan. The reflective materiel was from a Mylar emergency blanket I had on hand - no other specific reason I chose it.

So it sounds like something specific to the UV light. I have found the light mix I have been using does seems to work well. As you mentioned it would still be interesting to see how varying this affects things.

I guess I should mention that I knew that my light mix was best all along - yea! Why, just the other day I was having lunch with my wife - Morgan Fairchild - when two of my best friends, Niels Bohr and Enrico Fermi just happened to stop by. Yea ... Enrico Fermi. They said the photons I picked were the very best! Yea, that's the ticket!
Last edited by OldIsNew on 29 Oct 2018, 22:00, edited 1 time in total.

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Hypersphere

29 Oct 2018, 17:47

@OldIsNew: Thanks for the further details about your photon optimizer apparatus. Glad to know that two of my favorite people, Niels and Enrico, approve. I'll be sure to mention this to Oppie the next time he drops by for some subatomic gossip.

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Menuhin

29 Oct 2018, 21:55

The close-up lit from above photo of these "OAK" switch housings makes these switches suddenly look like some kind of MoMA exhibition items. :shock:

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