Introduction: USB Typewriter Conversion Kit

About: I am an electrical engineer and professional dumpster diver who is currently in the process of moving my family from Philadelphia, PA to Portland, OR.

There is something very magical about typing on those old-school manual typewriters. From the satisfying snap of the spring-loaded keys, to the gleam of the polished chrome accents, to the crisp marks on the printed page, typewriters make for a sublime writing experience. Now, the USB Typewriter Conversion Kit lets you enjoy the magic of writing on a manual typewriter, without forfeiting the ability to use word-processing, email, web-browsing, or other modern desktop conveniences. Instead of fixating on a computer monitor, you can experience the simple joy of typing with ink on paper, and only look up at your monitor when you need to. Or, you can work on your typewriter alone, while discreetly saving your work to disk! (Your USB Typewriter will also make a nifty keyboard-stand for your iPad)

In these instructions, I'll help you breathe digital life into your old typewriter by converting it into a keyboard for your PC, Mac, or tablet computer. The USB Typewriter Conversion Kit will work on a wide variety of manual typewriters, from many different manufacturers and eras.

The hack is intended as a full keyboard replacement, so you can get rid of that piece of disposable plastic you call a keyboard and use the desk space for a classic, functional work of art -- A USB Typewriter!

Read on, and you'll see how easy the conversion process is -- anyone can do it, regardless of skill, and there is absolutely no soldering involved. If you are interested in performing this conversion on your own typewriter, you can purchase the USB Typewriter Conversion Kit at

The kit is designed to work on most manual typewriters, dating anywhere from the 1910s through 1960s. If you want to make sure your typewriter will work with the kit, simply look for your make and model in my Compatibility Guide, or email me at

Step 1: How It Works

The USB Typewriter Conversion Kit consists of three simple components, which come pre-assembled and ready to attach to the typewriter as shown.

  • The Sensor Strip - The Sensor Strip is a row of 44 gold-plated contacts, attached to a long circuit board which will be mounted underneath the keys, spanning the width of the typewriter. Each time a key is pressed, it touches one of these gold-plated contacts, and this contact is detected by the circuitry.
  • The Magnetic Sensors - Since the Space Bar, Shift Key, and Backspace Key do not touch the sensor strip, they are instead detected magnetically. Magnets are attached to these keys, and magnetically-activated switches are glued nearby. These switches can detect the change in the magnetic field whenever these keys are pressed.
  • The Control Panel - This circuit board reads information from the magnetic sensors and the sensor strip, then determines which key has been pressed, sending that information to the computer over USB. The control panel also has several important buttons mounted directly on it: they are CTRL, ALT, and CMD. The Control Panel is mounted to the side of the typewriter, so that these buttons can be accessed easily.

Step 2: Tools and Materials

This kit was designed to require very few tools to install. Here is what you will need:

  • A fine tool for scraping/sanding, such as a metal file, 80 or 100 grit sandpaper, a nail file, or a Dremel tool with a wire brush attachment.
  • A small flat-head screwdriver
  • A pair of pliers
  • A hot glue gun
  • Wire Strippers (optional but highly recommended)

You will also need the Easy Install Conversion Kit from, which includes:

  • 1 control panel that fits on the side of the typewriter
  • 1 sensor panel which fits underneath the typewriter
  • 4 magnetic switches for detecting Shift, Space, Backspace, and Enter
  • An assortment of magnets
  • A mounting bracket for your iPad or mobile device.

The project is open-source, so if you want to take a look at the design files that go into making these components, download them HERE.

Step 3: Mount the Sensor Circuitry (Video)

The first step is to mount the sensor circuitry under the keys of the typewriter. The flexible contact strip will be clipped to a piece of metal underneath your typewriter, so that each gold-plated contact on the flexible strip will be held underneath one of the keys. Each time a key is pressed, it will come in contact with one of the gold strips, activating the circuit.

Once the sensor circuitry is positioned correctly, hot glue will be used to hold the white circuit board in place.

It is hard to explain this part of the installation with pictures, so I have prepared a short video explaining how to install this circuitry on each of the most popular typewriter models out there. You should follow along with the video relating to your typewriter before reading on:

IMPORTANT NOTE: Some of the kits shipped in April of 2015 may have been shipped in an incomplete state! On these kits, the sensor circuitry was missing a strip of black gaffer's tape on one side. Before proceeding with the installation, please make sure there is a strip of black tape stuck to your sensor circuit! This circuit should be white one one side, and black (covered with tape) on the other! If you received a board that was missing this tape, email me at jack [at] and I'll send you a replacement right away. (Royal portable customers can ignore this message, since that kit does not need the tape.

Click on the brand name of your typewriter for instructions:
Portable Typewriters:
Smith Corona

Underwood Portable
Torpedo -- Video Coming Soon (email for instructions)

Desktop Typewriters:
Royal No. 10
Royal KMM, and KHM

Underwood No. 5 and Similar Models
Remington Quiet-Riter, Letter-Riter, and Travel-Riter Models

Step 4: Attach Control Panel

Before you attach the main control panel to the typewriter, take the four rubber bumpers that came with the kit and stick them onto the four white dots on the back of the control panel. These bumpers prevent the back of the circuit board from directly touching the metal typewriter frame.

The control panel should be affixed to the left side of the typewriter towards the back. I recommend you use a moderate amount of hot-glue to attach the sensor board, but you may instead use double-sided foam tape if you want a less-permanent bond.

Some control panels come equipped with Bluetooth radio modules, which is soldered to the back of the control panel. If your control panel has such a module, do not place the rubber feet directly on the module, and do your best to avoid getting hot glue directly on the module. It is OK if the metal part of the module touches the metal frame of the typewriter (they are both grounded).

Step 5: Connect Ribbon Cable

The grey connector on your ribbon cable plugs into to the connector on the bottom right corner of the control panel, as shown. If there is too much slack, introduce folds and bends into the cable to make it more manageable (see picture above).

Step 6: Connect Chassis Lug Wire

In this step, we need to create a solid electrical connection between the control panel and the metal chassis of the typewriter.

First, find a screw or bolt on the typewriter that is easily accessible. Next, remove this screw and strip away the paint underneath it with sandpaper, exacto blade, metal file, or Dremel. Finally, use the screw to securely fasten the chassis lug to the exposed metal of the chassis -- the picture above sums it up nicely.

Now, strip the other end of this wire and insert it into the hole on the Control Panel marked "C" for Chassis. Turn the tiny screw clockwise to clamp the wire securely in place. (see second picture above)

Step 7: Mount the Magnetic Switches

In this step, we will attach the three magnetic sensors, which will detect Shift, Space, and Backspace.

To connect your first magnetic switch, strip the two wires attached to it and insert them into any of the four remaining pairs of holes on the control panel (marked "1", "2", "3", and "4"). NOTE: Before inserting the wires, you may have to twist the tiny screws counterclockwise first to open the hole up wider -- after inserting the wires you should tighten these screws again to clamp the wire in place.

Next, while holding down the CMD key (the third button down on the control panel), plug the control panel into your computer with a USB cable. The control panel is now in TEST mode, and so the LED on the control panel will light up. Now, here is the magic part: take a magnet and move it close to the switch -- whenever it gets close enough, the LED changes color! Try it and see!

The magnetic switch has the amazing ability to sense whether a magnet is nearby or not, and we are going to use this ability to detect the space bar, backspace key, and shift key. The idea is simple -- we will attach a magnet to the key we wish to sense, then glue a magnetic switch nearby. Whenever the key is pressed, the magnet will move towards the switch, triggering it.

Your goal is to select an appropriately sized magnet (the greater the distance, the bigger the magnet), place it somewhere on the key you wish to sense, then find the best possible place on the typewriter's frame to attach the magnetic switch. You will know you have found the right place when pressing the key causes the LED to change color, and releasing it causes the LED change back.

Once you have found the right place for your magnetic switch, glue it down with a very modest amount of super-glue or super-glue gel. Repeat this process for all the reed switches you plan to use. At the bare minimum, you should use a magnetic switch on the Shift key and Spacebar, and, optionally, Backspace as well.

The magnetic sensors currently included with the kit have neat mounting holes on one side. In certain situations, you can use these holes to screw the sensors onto your typewriter, instead of gluing them. However, in most cases, you won't need them, so it is OK to cut them off with scissors or wire clippers (see before/after picture).

Using the one remaining set of connections on the Control Panel, you can add an additional magnetic switch to the Return Carriage lever so it acts as an "Enter" key -- however, this is much more difficult to do. Therefore I recommend that you instead assign "Enter" to an unused key on the main keyboard (like the otherwise useless "½ / ¼" key) -- this re-assignment is done in the next step.

Step 8: Calibrate

When you first plug in the USB Typewriter, it has no idea which contacts on the Sensor Panel correspond to which typewriter keys. Luckily, the USB Typewriter has a "Calibration Mode", which sorts this out for you automatically.

To access Calibration Mode:
1) With the USB cable unplugged, open up Notepad (on Windows) or TextEdit (on Mac).
2) Next, hold down the CTRL button (One of three white buttons located on the Control Panel) while plugging the USB cable in.

A message should appear on your computer screen (See photo above).

You will then be prompted to type each letter of the alphabet, all the numerals, punctuation marks, and a few other keys. Just type the corresponding key on the USB Typewriter. A number identifying which key you pressed will be displayed on the screen.

You can also hold down the ALT button on the control panel while typing a key to assign a secondary function to a key. Example: you may want to assign ALT+Backspace to be Escape, or ALT+Space to be Tab.

In addition to the Calibration Mode described above, there are two additional calibration modes you can access:

"Manual" Calibration Mode: Hold down CTRL+ALT when plugging in to access Manual Calibration Mode. In this mode, you can scroll through an extended list of characters and pick the exact character you want to add to your keyboard layout. This way, you can fine-tune your keyboard, adding assignments for less common characters and/or characters from foreign languages.

Sensitivity Adjustment Mode: Hold down ALT when plugging in to access Sensitivity Adjustment Mode. In this mode, you can control how long a key must be held down before it registers. You can also control how long a key must be released before it is recognized as released. You can also reduce the typewriter's sensitivity to "double-taps": that is, keys being pressed twice in succession.


The most common issue seen when calibrating is when the same number appears next to each letter, like this:

A: 23
B: 23
C: 23
D: 23
and so on....

This problem occurs because one of your gold-plated contacts is touching a key, or some other piece of metal inside the typewriter. Therefore, the typewriter's circuitry assumes you are holding that key down. Check each gold contact and make sure it is only touching its corresponding key when that key is being pressed.

Step 9: Enjoy!

Your typewriter is now completely converted and ready for a test drive! I recommend you read the operating instructions first, though -- I have the full instruction manual posted here. This manual will show you how to switch between USB, Bluetooth, and SD card mode, and how to protect your platen from damage if you don't plan on using the typewriter with ink ribbon or paper.

Optionally, if you plan on using an iPad or other tablet with your kit, you can fashion a support to hold your iPad on top of the carriage by following these simple instructions. If you don't have the Bluetooth version of the kit, you may also need the correct cable for your iPad, which you can find here. <-- Update: All kits are bluetooth-enabled now.

Enjoy your awesome new (and old) USB Typewriter!

Check out my website to get more information about this mod, watch some nifty videos of it in action, or pick up a kit for your own typewriter hacking pleasure.

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