Listen to this audio file:

It is an encoding of a 6-letter word using

In this example, we use four different frequencies to represent the pairs of bits 00, 01, 10 and 11. The lowest frequency (low pitch) represents 00, the next frequency represents 01, the next frequency represents 10 and the highest frequency (high pitch) represents 11.

The duration of each bit is 0.5 seconds, and the frequency is constant during each symbol (00, 01, 10, 11).

Listen to the audio file and write down the sequence of symbols. Then, decode the sequence using an ASCII table (8 bits per character). Tip: the first symbol you hear represents the leftmost two bits of the first character.

Listen to this audio file:

It is an encoding of a 6-letter word using

In this example, we use two different amplitudes to represent the binary digits 0 and 1. A low amplitude (low volume) represents a 0, and a high amplitude represents a 1.

The duration of each bit is 0.5 seconds, and the amplitude is constant during each bit.

Listen to the audio file and write down the sequence of bits. Then, decode the sequence of bits using an ASCII table (8 bits per character). Tip: the first bit you hear is the leftmost bit of the first character.

Listen to this audio file:

It is an encoding of a 6-letter word using Morse code.

In Morse code, each letter is represented by a sequence of short and long pulses (sounds), with gaps between letters. Decode the word and enter it in the box below. You can use any online resource to look up the Morse code alphabet.

It may be helpful to first write down the Morse code sequence you hear (e.g. using - for a long sound and . for a short sound), and then look up the letters.