Build in 1984 and equipped with IBM capacitive buckling spring switches this keyboard weights almost three kilograms thanks to its metal backplate and cast zink lower housing.

Facts

Model no. IBM PC 5150 keyboard
Manufacturer IBM
Manufacture Date 1985
Case Cast zink botton, hard plastic top
Plate Steel
Switches IBM capacitive buckling spring
Keycaps PBT dye sublimated
Dimensions 500 × 200 × 57 mm
Weight 2680 gram
Controller/Software Teensy++ 2.0 / Soarer

Highlights

The keyboard is over 35 years old and still works perfectly and sounds great as well. The space bar is massive (18cm or ~ 10u). With the XT Layout its quite usable, but I miss some keys in the bottom row. I used it after the restauration for about half a year but was not able to get up to a good speed with it.

I own this keyboard since my childhood. After my Comondore 128D the IBM PC was my second computer and I really liked the keyboard. I kept it after the IBM PC was replaced by other computers. Due to the XT protocol used by the keyboard I was not able to use it for a long time. Back in 2017 I found a tutorial online how to convert the keyboard using a teensy and the Soarer Firmware.

Layouts

This is a layout i used back in 2017. Recently I tried using QMK (xt-usb converter) on the teensy but got ghost key presses and other problems with it.

Black legends are the normal layer. Blue legends are the FN layer and the green legends are toggleable with the Num Lock key.

Firmware

I haven’t published the config for the soarer firmware to the public. The work-in-progess config for QMK is on Github but not working well as of now.

Images

A look inside the keyboard. The teensy is connected to the original controller and connects with a custom made coiled USB cable. I still have the original cable which is really thick, but I wanted to keep it unmodified. Some folks use boxes or inline converters from DIN-Plug to USB but I wanted to keep the setup as clean as possible.

Switch assembly with the case removed. At the top you can see the teensy and the original PCB with the controller and the decayed foam which I will have to replace at some point.