HOW are images captured onto magnetic tape?

Question

Using light & magnetism... how are images & sound recorded, preserved & reflected?

Answer 1

The camcorder has 2 sets of transducers.

For audio, it has a microphone which converts air pressure to voltage. The voltage is sampled 48K times per second in an A/D and the digital result is saved.

For video, it has a CCD array. Each element in the array is charged by light hitting it. The elements are addressed digitally and read out in sequence to an A/D and the digital result is saved. The entire array is sampled once at the frame rate, 30 fps in North America, 25 fps in Europe and then reset.

The tape, DVD or hard drive is a storage device for the digital bytes obtained by the camcorder. A compression alogrithm is applied to the visual content, which reduces the number of bytes to be recorded by a factor of about 6. In tape, a head spins across the surface of the tape. On record, it lays down a sequence of magnetic pulses that correspond with the digital data and leaves a magnetic pattern on the tape. On playback, the spinning head picks up the same magnetic pattern and can then stream the data to be decoded. Both visual and audio data are interleaved on the same serial data stream.

Answer 2

Light and sound are turned into electrical impulses that effect the magnetic charge of the tape. When you run the tape through a player the player has an eclectic field at the heads that are distorted by the magnetic charge on the tape and that is how it is done.

Radio Shack sells cheap little books that will explain it all and even give you schematics to build a voice to light transmitter and receiver.

Answer 3

tape is just a form of data storage. You can store any type of information you like on there. So long that you know what format to expect that data in, it's easy to decode it and do anything you want with it after that.