Simulation of the recording and playback of sound waves using a magnetically encoded waveform on a tape.
To try this
simulation:
Click on the "PLAY" button to play back the sound on the tape. Click on the "RECORD" button to record a sound.
What's Going On?
When you speak into the microphone, the sound from your voice is amplified and sent to an electromagnet. The recording head in a tape recorder is a tiny electromagnet that responds to sound.
The magnetic recording head is designed to magnetize recording tape as it passes by the gap.
In our model, the magnetic field in the gap is detected by the compass. The magnetic field changes as your voice goes from loud to soft. A motor activates a model tape recorder. As you speak, your voice is sent to the magnetic head and the magnetic fluctuations are recorded on magnetic tape. As the tape comes around again, the magnet just in front of the recording head erases the magnetic patterns on the tape so it is ready to use again.
There's More!
Magnetic recording has been around for decades. One of the first magnetic recording devices used a magnetizable wire instead of tape. As time went on, it was discovered that iron oxide impregnated in paper tape made a passable form of recording tape. The iron oxide particles would magnetize and retain their magnetization when passed over an electromagnet and the tape was easier to spool and handle.
Today's tape is a highly developed Mylar film upon which sophisticated mixtures of uniformly graded magnetic particles are bonded. The characteristics of the tape are very repeatable and the coating does not fall off to clog the workings of the tape machine. The tape is put into cassettes and cartridges for VCRs and DATs and even cut into disks for your computer!
