After being fascinated by teletype machines for many years, Bob Coggeshall has demonstrated a method of controlling a vintage Model 15 teletype with a Raspberry Pi. Doing so is a lot simpler than you would imagine, apart from powering the TTY a simple 24V DC data line is controlled with a relay - which can easily be switched with an N-MOSFET and a GPIO pin.
Futhermore Bob has provied a simple HTML interface that can be accessed from an network-connected device, allowing text entry and controls of the TTY's power and features. It's a great way to understand the very basics of data transmission and also hardware to Raspberry Pi interfaceing.
If you're making a similar project and need to control large currents with digital GPIO - you'll need a MOSFET. We've got you covered with our NDRIVE: N-MOSFET driver/output module:
This high-power N-MOSFET module lets you switch high-current loads using a tiny microcontroller. Perfect for controlling that set of traffic lights mounted in your living room, electric motors via PWM and other automotive projects such as switching high-power 12V lights and high wattage LEDs. For more information and to order, visit the product page.