Some of the factors to be discussed are more controllable than others. For example, you can normally decide the storage conditions and level of access to an archive collection.
However, you do not always have control over the quality of the tape wind, or the brand, type, and format of the tape media on which the information is stored.
Magnetic tape should receive the same kind of care that you would give to a valuable book or important photograph. In general, handle the tapes with care, keep them clean, and apply common sense:.
Refer to the Ampex Guide in the Appendix for more information. Magnetic tapes do require some unique care and handling precautions. Because they are a magnetic form of storage, exposure to strong magnetic fields must be avoided to prevent information loss. This is generally not a problem, unless the materials need to be transported or shipped.
Tapes that are frequently accessed may have a reduced life expectancy due to wear and tear. The life of the media may not be determined by data error rates, but by the life of the media housing. In one instance, the life of a tape cassette was limited by failure of the cassette door, not because of any fault of the tape media. How many insert and eject cycles will your media be required to handle?
This may limit the life of the cassette. The more a tape or cassette is handled, the more it is contaminated with fingerprints and debris. It is also exposed to less than ideal conditions, especially if the materials are removed from the building in which they are normally stored. Every time a VHS cassette is loaded into a recorder, the recorder mechanism pulls tape from the cassette.
This mechanism can damage the tape if the guide pins are not properly aligned. Debris on the loading mechanism can scratch the surface of the tape. Also, when a tape is removed from a recorder, the tape must properly retract into the cassette, otherwise it will be damaged when the cassette doors close and the tape cassette is ejected from the recorder.
Most of us have probably had experience with a VHS deck that has eaten a tape. Because of potential damage to the tape, it is important that the tapes be inserted and ejected at areas of the tape that contain no recorded information. Care must be exercised to ensure that tape collections are not harmed when they are transported.
Collections should be transported in the spring or the fall when outdoor temperatures are moderate, if possible. Properly wound tape reels can survive greater variations in temperature and humidity without permanent damage than can poorly wound tape packs. Tapes and cassettes should be shipped in the same orientation as they are stored — on edge — with the weight of the tape pack being supported by the reel hub.
Tapes that are shipped in the flat position are particularly subject to damage from dropping and other forms of shock. This is especially true of tapes that experience large changes in temperature during shipment or tapes that are poorly wound. Media should be protected from damage due to shock by packing them in materials that will absorb shock special packages, bubble wrap , using special labeling, and transporting them in appropriate vehicles.
Shock-absorbing packaging will often have the added advantage of providing insulation that helps protect the media from large swings in temperature and humidity. Exposure to strong magnetic fields must also be avoided to prevent information loss. Some of the detectors used to screen luggage in overseas airports have been known to partially erase tapes. Walk through metal detectors and X-ray scanners do not pose a threat to recorded information. Some hand-held metal detectors can cause problems since they use strong magnetic fields.
Storing magnetic tape in a clean, controlled environment is the most important precaution you can take to extend the life of the media. High temperatures, high humidity, and the presence of dust and corrosive elements in the air all affect the physical components that make up magnetic tape and can result in loss of readable data through decreased magnetic capability and deterioration of the binder or backing of the tape.
Too low temperatures should also be avoided. Rapid temperature changes are also undesirable as they introduce stresses in the wound tape pack. Tapes that are to be played in an environment different from the storage environment should be allowed to acclimate to the new temperature.
For years tape manufacturers have recommended that you store your tapes in a cool, dry place. Furthermore, this reaction will proceed more slowly at lower temperatures. The latter is also true for the magnetic pigments — they will degrade more slowly at lower temperatures. Finally, to reduce unnecessary stresses on the wound tape that could result in deformation of the backing, a limited variation in temperatures and humidities is recommended.
See Figure 6. This results in distortion of the tape backing and an increase in permanent dropouts as wound-in debris is forced into the tape magnetic layer. Many layers of tape before and after the debris can be affected by impressions of the debris. Layer to layer adhesion, known as tape blocking, also can result after long term storage at elevated temperatures.
High humidities will also cause increased tape pack stresses as the tape absorbs moisture from the air and expands, causing distortion of the tape backing and an increase in permanent dropouts. Fungal growth is also possible at high humidities and temperatures. Molds can live off the binder polymer and added components.
This is yet another cause of binder breakdown in high humidities. Hairy growths at the edges of the tape are a sign of mold. The spores that are produced on this fuzz can get onto the tape surface and cause many dropouts. Changes in both temperature and humidity can also cause mistracking problems on helical scan recordings See Section 2. Substrates will expand or shrink with changing temperature and humidity just as metals do in heat or cold.
The substrate films are not completely balanced in their reaction to these changes in temperature and humidity. In other words, they stretch and shrink differently in length and width directions.
This causes a change in the angle of the recorded helical scan tracks. Most of these changes are recoverable by returning to a temperature and humidity close to the one at which the tape was recorded. However, heat can also cause premature aging of the substrate in the form of nonrecoverable shrinking and stretching.
Figure 6. Source: Ampex. Reprinted with permission. Kodachrome Photo Slides. Get more Vitamin D. Play Brain Games. Plan a Perfect Family Weekend. Preserve your Recorded Memories. Create a Highlight Reel. Enjoy a Family Watch Party. While you're in there, you could also clean any belt pullies and rubber drive wheels with the alcohol to eliminate any slippage issues.
Shiny rubber could mean slipping is occurring. Last edited: Feb 26, I have a problem with the tape not moving at all. Sometimes rapping the cassette on a hard surface loosens the tape pack. Or transferring the tape to another housing solves the problem. AnalogDigit , Feb 27, There are many causes. I'm assuming by 'eaten ' you mean a length of ribbon outside the cassette housing.
If the tape is eaten almost immediately, then the take up spool is not rotating or does not have enough torque, test it by pressing play and grasping it, you should feel some resistance. If this is not the case, a rubber belt or idler has probably perished.
If, however, the take up feels Ok, check the rubber pinch roller is not sticky. If the tape gets eaten after a few minutes, especially if the sound drops out or flutters first, then the pinch roller may be very dirty, hard, cracked or barrel-shaped. This leads to uneven winding and the tape layers soon jam against the cassette shell. A boombox is not a good choice for playing your old tapes. They tended to use the cheapest mechanisms which don't handle the tape very well.
Ask on freecycle or equivalent for a proper tape deck. Puddintane , Feb 27, Messages: 3, Location: San Diego. There are two common ways tapes get eaten. The first is where the tape gathers around the capstan. This usually occurs when the takeup reel stops turning. The second is where the tape migrates out of the correct path and crinkles. This is caused by a tape path alignment problem, often due to pinch rollers that have become misshapen or misaligned with age.
Fred Longworth , Feb 28, Messages: 6, Location: Lenzburg, IL. Kahoona , Feb 28, Messages: Location: New Jersey. Many times the cassette "shell" itself is the culprit.
I always make sure the tape spools easily in both directions within the shell prior to playback - the old "BIC" pen works perfectly or a hexagonal pencil. Messages: Location: Kansas City. The C tapes are said to have this problem more, since the tape is thinner.
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