Build a Code Practice Oscillator: Your First Morse Project KEYS AND INSTRUMENTS | MORSE CODE WORKS Before the first contact, before even the first lesson sticks, there is a small box that beeps when you press a key. The code practice oscillator is the oldest beginner project in Morse, and building one teaches the first real lesson: this hobby rewards people who make things. The circuit can be a 555 timer, a pair of transistors, or an afternoon with a microcontroller - the electronics matter less than the ritual. Wire your key to it, set a tone your ear enjoys, somewhere in the friendly 600 to 800 Hz range, and your practice suddenly has a voice. Learners who like their sidetone practise longer. It is that simple. Key points - Add a headphone jack early - households appreciate it - A straight key on an oscillator teaches spacing better than any app setting - Keep the oscillator by the radio later for key adjustments - Label your build with the date; first projects become heirlooms Try it yourself Translate any text to Morse code and hear it with sound, free: Morse Code Works