Video and audio tapes, such as VCR tapes and music cassettes share some common characteristics. Interestingly enough, they also have something in common with floppy disks. All are made from magnetic media. Magnetic media is composed of a polyester or polyethylene base with magnetic particles glued to it. Video and audio tapes have a long strip of film wound on spools inside a cassette box. Floppy disks have a plastic platter inside them, which spins. Both the film and the platter are coated with magnetic particles made of ferrous oxide. These magnetic particles record and store information.
Magnetic tape recording was first developed in Germany in 1934 but did not achieve world recognition until Ampex introduced the first professional quality audio recorder in 1948. Eight years later, Ampex introduced the first practical videotape recorder. Floppy disks were developed in the late 1960s by the IBM company, although those disks were rather larger than they are today. The first floppy was eight inches across.
Although tapes and disks are made up of similar materials, the manner in which their information is accessed is slightly different. Tapes are recorded and read sequentially. That is, in order to play a part in the middle, the beginning must be played or fast forwarded through. There is no way to "jump" to the part that is wanted. Disks, on the other hand, are recorded and read via random access. The platter is made up of many rings and sectors. Each sector holds information and can be accessed at any time. No fast forwarding is necessary with disks; just select the part that is desired.
|Roll over the disk to see inside. The green area represents a sector. disks, unlike tapes, are random access.|
With the advent of CDs and DVDs, magnetic media are becoming less popular. However, some of our favorite music may not yet be available on CD, our favorite taped television show might still be on videocassette, and perhaps we haven't quite upgraded the computer to having a dvd burner. Magnetic media, unfortunately, won't last forever.
The glue, called the "binder," that holds the magnetic particles in place can be easily damaged from high levels of heat and humidity. It can become soft and sticky, or it can become quite brittle. In tapes, soft sticky binder can glue the tape together, and gum up the player. In floppies, it prevents the platter from spinning. Brittle binder flakes off the plastic base, taking the magnetic particles (and thus the information recorded on the particles) with it.
Magnetic media can also be damaged by dirt and dust, which can create scratches that erase media. Dust also can damage tape playback heads and cause floppy disks readers to skip or lock up in an area of the disk.
Finger prints can lift magnetic particles off the base or cover the particles over. There is less likelihood of fingerprints or dust on a 3.5" floppy than on the older 5.25" disks, as a sliding cover hides the platter from sight. VCR cassettes also have a cover which protects the tape, while audio cassettes do not.
Magnetic media have a short life expectancy. Careful treatment may increase their ability to be played to 30 years for tapes and, for disks, up to and even beyond 3 million passes. If your collection consists mostly of professional productions, cassettes or films that are still in print, buying a new copy is probably the best option. For homemade, old, or out-of-print videotapes, cassettes, or floppies, proper storage and handling practices will prolong the life of the item. Transferring the information from one tape or floppy to another one, or to an entirely different media such as a CD or DVD, is a very good idea, though it will not be a permanent form of preservation (see Protecting your CDs and DVDs for more information). Proper environment, storage, and handling practices can prolong the life of magnetic media.
Temperature and humidity play a major role in the destruction of magnetic media. Extremely high temperatures cause the binders to break down and become either sticky or brittle. Sticky binders can break machines, while brittle binders will lose data. Extremely high humidity can warp the platter inside a floppy and stretch of video or audio tapes. Changes in temperature and humidity can cause condensation inside the cassette box or disk. It will also cause the materials from which the tape or disk is made to expand and contract, which they will do at different rates. This expansion and contraction can cause the entire unit to warp.
Try to store tapes and disks in a stable cool environment. Do not, for instance, leave your favorite audio tape in your car in the hot Florida sun. It could literally melt. Do not leave disks on top of your computer monitor or any other heat generating appliance. If a tape or disk has been in the heat for any amount of time, allow it to cool for a while before playing it. The plastics and binders become softer and more easily damaged while very hot .
Although a stable 65º with 30% humidity is the ideal storage environment for magnetic media, it is hard to achieve in Florida. As most computers work best in a cool climate, storage of the floppies in a cooled computer room is one option.
Dust also plays havoc with magnetic media. Dust particles can scratch the plastic base, erasing information. Dust can also damage cassette players, VCRs and disk drives. Dust and vacuum regularly in the areas where these devices are kept and store tapes and floppies inside cases, jackets, or boxes to keep the dust out.
When not using video or audio tapes, store them inside their cases, on-end like books. Store floppies in their jackets or in upright cases. Avoid over stuffing cases, as cramming disks together can damage them. Do not store disks under anything heavy.
Any magnetic source, such as security systems, magnets, transformers, and electric motors, can affect the magnetic particles on tapes and floppies. Do not store magnetic media in a cabinet with a magnetic lock or catch. Interestingly enough, some types of lamps also produce magnetic fields, keep magnetic media away from the ballast in florescent lamps and the bases of high intensity lamps.
Excessive or constant vibration can also disturb the magnetic field. Periodic trips in the car should not hurt anything, but sitting for any length of time on a running clothes dryer will.
Clearly label your tapes or disks so you know what they are without having to play them. If they become damaged, you will then know whether they are worth the expense of recovery. When labeling floppies, write on the label first, before attaching it. If the label is already attached, use a felt tipped pen, rather than a ball point, to lessen the chance of damaging the platter inside. If you want to re-label a disk, peel the old one off first, rather than stacking labels. Stacked labels can be too thick for the reader and peel off inside your computer.
Do not use paper clips, rubber bands, or other fasteners on a floppy disk. If you need to mail a floppy, use a stiff piece of cardboard or other unbending material to help support it through the mail.
Fingerprints can create havoc on each type of magnetic media. Although disks have a protective slider in place, accidental harm can still occur if the slider moves while you are handling the disk. Video tapes are less susceptible to fingerprints than audio tapes, but again, be careful not to shift the cover. Do not attempt to clean fingerprints from magnetic media. Any cleaner or swab can do more damage to the media than the fingerprint has done.
Be sure your tape player works properly before inserting a tape. A broken machine will cause irreparable damage to a tape. If you are not sure if a machine is working, try a tape of no value in it first. Do not leave a tape in the player on Pause for any length of time, as it stretches the tape. Playing a damaged tape can ruin a machine.
With floppies, be sure the disk drive is dust free. Dusty drives can cause scratches on the platter. Invest in a drive cleaner for your machine. Similarly, invest in head cleaners for your cassette player and VCR. Dirty heads can scratch tapes.
Tapes need to be used in order to last. Play them once in a while, or fast forward and rewind them once or twice a year. Video tape re-winders often can do damage to tapes, as they are uneven in their tension, so use your VCR instead of a re-winder.
Floppies, on the other hand, do not need to be played in order to work. Storing them upright and not playing them is just fine.
Data recovery is possible with both tapes and disks. For more information on companies that specialize in recovering information from old or corrupted tapes and disks, see Conservation On-Line: http://palimpsest.stanford.edu/
When in doubt, make a copy: Copies are inexpensive to make and are your only absolute protection against the loss of the information. Break off the Record tab on a tape cassette to protect the recording. Slide the write protect slider to open the hole to protect a floppy disk. And for very important computer information, make copies and store them off site.
If you are considering converting your tapes to either CD or DVD, remember that these media are also not permanent and come with their own preservation concerns. For more information on this, see Protect your CDs and DVDs