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TI-99/4A Mitsumi Keyboard Cherry MX upgrade kit
KEYBOARD/4A-99
Sold by Troy Schrapel (visrealm)
$12.00
No tax for United States [change]
Stock available: 4
What is it?
A Cherry MX compatible upgrade for the infamous Mitsumi mylar keyboards that plague many unfortunate Texas Instruments TI-99/4A computers.
The full upgrade consists of a new PCB and (optionally) a handful of 3D printed parts. The original look is maintained by re-using the original Mitsumi key caps (and some other original parts). Add the switches of your choice and you're set! A brand new keyboard for your TI-99/4A.
Note: This is an upgrade. As such, you will need an original TI-99/4A Mitsumi (or Archer) Keyboard as a donor for these parts:
- Key caps
- Alpha lock switch
- Space bar supports
- 15p Ribbon cable
- Metal support brackets
You can easily identify a Mitsumi keyboard through the bottom of your TI-99 console as it will appear brown through the vents.
3D printed parts
If you choose to print your own parts, all STLs are available in the product GitHub page. Alternatively, they can be included with your order as optional add-ons.
What do you get?
- 1x KEYBOARD/4A-99 PCB.
Add-ons
Mounting kit (optional)
- 2x Keyboard mounting brackets with brass inserts
- 2x Backing strips for Mitsumi metal support bars
- 6x Screws for mounting brackets
Key adapter kit (optional)
- 49x keycap adapters to suit Cherry MX switches and Mitsumi keycaps
- Special double-wide Shift key adapter
- 2x Spacebar support mounts with brass inserts
- 4x Screws for spacebar mounts
Akko switches (optional)
- 47x Akko Creamy Black Pro key switches
Installation video
Links to code and documentation
Product HS Code: 850490
Shipping policy
All orders are usually shipped with tracking within 2 business days.
US customers please note import tariffs and associated fees will be collected during checkout. You will not need to pay any extra upon arrival.
UK customers please note VAT will not be collected and orders with items totalling under £135 (approx. €150) should not attract any import duties.
EU customers please note VAT will be collected and paid for all orders. You should not need to pay any extra upon arrival, however extra charges do apply when the items total over €150.
If the store is showing shipping unavailable to your location, please reach out and I will add a shipping rate for you.
The seller
Designer of modern hardware replacements for your retro machines.