In the simplest version of a telephone, it doesn't record anything or convert it to radio waves. Here's Alexander Graham Bell's original patent diagram:
You speak into the cone at A. The sound waves move the bar at a causing the magnet at B to change the electricity (coming from the power source at E). That means that the electricity comes out in a wave pattern matching the sound.
That electricity is transferred to the other end, where the process is reversed. The magnet at f will get more and less powerful as the electricity varies, causing a membrane i on the other end to go back and forth. That causes the air to move in a wave pattern which is (more or less) identical to the original sound. (The sound is a good deal quieter, so the cone L concentrates the sound. Later, amplifiers would be added.)
Note that nothing is ever recorded anywhere. The voice pattern is transferred essentially instantly into the electricity, and then converted back to waves on the far end. Like the voice, it's gone as soon as it passes.
It never needs to become radio waves, though you can also build a wireless device (i.e. a "radio") that does precisely that. A modern cell phone uses some of the same basic ideas, using the voice to make a variable current with a magnet and using a magnet on the far end to drive a speaker, but all of the intermediate bits are totally and utterly different.
You speak into the cone at A. The sound waves move the bar at a causing the magnet at B to change the electricity (coming from the power source at E). That means that the electricity comes out in a wave pattern matching the sound.
That electricity is transferred to the other end, where the process is reversed. The magnet at f will get more and less powerful as the electricity varies, causing a membrane i on the other end to go back and forth. That causes the air to move in a wave pattern which is (more or less) identical to the original sound. (The sound is a good deal quieter, so the cone L concentrates the sound. Later, amplifiers would be added.)
Note that nothing is ever recorded anywhere. The voice pattern is transferred essentially instantly into the electricity, and then converted back to waves on the far end. Like the voice, it's gone as soon as it passes.
It never needs to become radio waves, though you can also build a wireless device (i.e. a "radio") that does precisely that. A modern cell phone uses some of the same basic ideas, using the voice to make a variable current with a magnet and using a magnet on the far end to drive a speaker, but all of the intermediate bits are totally and utterly different.
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