Detailed instructions for use are in the User's Guide.
[. . . ] Therefore, it is simply good common sense to take whatever measures are necessary to ensure that: 1. Fortunately, proper media care and handling is neither difficult nor expensive. Simple, easy-to-follow principles and practices, when properly implemented, will help ensure trouble-free recordings.
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Recommended Practices
GENERAL
1. Keep media away from all stray magnetic fields; even weak magnetic fields can cause erasures. [. . . ] Stray fields can come from a wide variety of sources, including loudspeaker magnets, fluorescent tube ballasts, handheld metal detectors (such as those used by airport security personnel), electrical transformers and especially electrical induction motors. The magnetic fields from these devices can cause an increased low frequency noise or higher levels of print-through. Other devices such as walk-through metal detectors and radar signals generally do not cause problems unless these signals are of extremely high strength. Fortunately, this is a rare situation.
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Unlike photographic film, X-rays do not affect magnetic recordings in any way. Problems from stray magnetic fields are very rare, even for recorded media shipped internationally without special precautions. However, it is a comfort to know that the magnetic field strength between the source and the target diminishes at a logarithmic rate as the distance increases. This means that even if the tape is near a magnetic source, the chances of it affecting the recording on the tape are very small unless the tape is very close to the source. Compared Coercivity of Various Media
Coercivity (kA/m) 200
DDS-3, DDS-4 DVCPRO
180 160 140 120 100 80
S-VHS TR-3, TR-4
LTO-1 SDLT-1, DLT-IV D-5 DDS-2 HDCAM, Hi8 D-3, Digital Beta, DLT-III, Beta-SX, Beta-SP 8mm, D-2 DDS, DAT, MiniDV
60 40
U-matic-SP, Betacam Hi-Bias Audio, U-matic 3480
Low-Bias Audio
20 0
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Environmental Conditions
TEMPERATURE
All current magnetic tapes, with the exception of magnetic evaporated tapes (e. g. , AIT, miniDV, Mammoth, etc. ), are composed of a formulation coated onto the basefilm (polyester or equivalent chemical compound). The magnetic formulation contains a variety of chemicals, including head cleaning agent, binders, surface lubricants, plasticizers, dispersants and of course, the magnetic particles. The temperature conditions recommended by many media manufacturers are dictated by a combination of the basefilm, binders and other components used in the tape itself and/or the plastics used in the cassette shell. The need to maintain dimensional stability of the cassette shells and the tape are critical factors in determining an appropriate operating range of temperatures. The basefilm on which the magnetic formulation is coated is somewhat temperature sensitive. This "growth" or "shrinkage" (which can be quite significant) may create stress within the tape pack that could result in physical damage to the tape. The magnetic particles of the formulation remain relatively stable and unaffected by extreme temperature.
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HUMIDITY
Except for metal evaporated tape, all magnetic tape uses some form of binder system. Acceptable Operating and Storage Conditions for Major Data Tapes
Operating Conditions Temperature 5 to 45C (41 to 104F) 15 to 55C (59 to 113F) 10 to 45C (50 to 113F) 10 to 40C (50 to 104F) Humidity 20 to 80% RH 10 to 80% RH 10 to 80% RH Operating Conditions Temperature Humidity 5 to 32C 20 to 60% RH (41 to 90F) 5 to 32C (41 to 90F) 16 to 32C (61 to 90F) 20 to 60% RH 20 to 80% RH
DDS-1, DDS-2 DDS-3, DDS-4 LTO, LTO2
DLT-IV, S-DLT
20 to 80% RH
16 to 32C (61 to 90F) 20 to 80% RH 18 to 28C* 40 to 60% RH* (64 to 82F)*
* For archive
Figure 5. Safe Storage Conditions (based on SMPTE RP-103)
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Physical Damage
SURFACE QUALITY
As mentioned in the Cleanliness section, any surface abnormality may cause a spacing loss. Surface abnormalities include dirt and debris, physical damage to the tape surface, and physical and magnetic scratches. Typically dirt and debris accumulate on, and protrude above, the media surface. The superfluous particles may be firmly attached to the surface or they may be transitory, i. e. , the particle may be removed by the head during contact. In the latter case it is usual for a single particle of dirt or debris to cause only one instance of spacing loss (drop out) and then seemingly disappear. However, a more permanent single particle of dirt may cause several instances of spacing loss. Even minute particles may cause impressions in adjacent layers of tape as that particle is wound into the tape pack itself. [. . . ] Although the tape pack leaves our factory with perfectly flat surfaces, its condition is potentially changeable by various usage conditions and environments. This is why we ask you to handle and use a tape under the proper conditions. Also please make sure that the tensions of the transports being used are always adjusted according to manufacturer's recommendations.
EDGE QUALITY
Physical damages to the edges of recording media also create a potential for inferior recordings. Magnetic recording media is precisely cut or slit to very tight tolerances on a slitter of exceptional precision, creating perfect edges. [. . . ]