This project show how to build a little morse transmitter using an MSP430G2231 MCU.
The device can transmit in two modes:
- serial, getting the characters from a COM port and translating them into morse code;
- manual, using the key switch.
In serial mode, one character at a time is read from the COM port and transmitted as morse at 15 WPM. To better understand how morse code works, read this .
Morse keying is achieved toggling an output pin connected to the oscillator power pin, thus getting a pure CW mode.
The device is powered with 2xAA batteries, and the power consumption is kept to a minimum thanks to the Low Power Mode when not transmitting. You may add a second 4xAA supply for the octal buffer in order to increase RF power.
Step 1: BOM & Tools needed
- 1x MSP430G2231 Texas Instruments MCU
- 1x 74HC240 Octal buffer
- 1x Oscillator (operating frequency should be in the 10/12m CW band (24/28 MHz))
- 2x 220 ohm resistors
- 2x 1 kohm resistors
- 2x LED (different colors are better)
- 2 push-buttons (included in the Launchpad, you may want to use a better switch for morse keying)
- 2 AA batteries (you may want to use a separate 6V (4AA) supply for 74HC240)
- 1m electrical wire (9 AWG)
- soldering iron
- wire stripper
- breadboard or stripboard
- TI's Launchpad board
- mini-usb cable