Frequently Asked Questions

NTSC video recorders operate at a different speed than PAL video recorders. The following table shows you the length of tape required when transferring PAL programmes to NTSC.

• Never leave a cassette tape in direct sunlight
  If a cassette tape is left in a place that has high temperature or exposed to direct sunlight - such as the dashboard of a car - both the shell and the tape can be severely damaged. Afterwards even though the cassette may look normal, it will not sound right. Remember that cassettes love the shade.
• Never expose a cassette tape to magnetism
  Certain equipment, such as televisions and speakers, have strong magnetic fields that will destroy tape recordings. All the time and care invested in a cherished music tape may be wasted if the cassette is placed close to such equipment.
• Avoid high humidity
  Moisture on tape will cause a tape transport problem called slip-stick.
• Never touch the tape itself
  Handling the tape in a cassette will cause minute quantities of oil and dirt to be transferred from one's fingers to the tape surface. This can lead to noise or other unwanted effects during playback. Tape is also easily scratched, so it is wise to leave it inside the protective cassette shell.
• Never leave a cassette tape in a dusty place
  Since the audio cassette shell is not completely sealed, dust can come into contact with the tape, especially if the cassette is not replaced in its plastic case after use. Dust on the tape can lead to noise and dropouts.
• Never try to clean a cassette with paint thinner or benzine
  If the outside of a cassette tape becomes dirty, it should be wiped with a soft, dry cloth. Solvents such as turpentine and benzine must never be used, they will cause irreversible damage.
• Never take a cassette tape apart
  The two halves of a cassette shell are held together with five screws, but these should never be touched. Once a cassette is disassembled dust can enter, and also it is very difficult to put everything back together again. Even if all the components seem to be in place, the tape will not run properly and reproduction will be impaired.
• Always put a cassette tape back in its case after use
  The plastic case that every cassette tape comes in plays a very important role in protecting the cassette from dust and other contamination, as well as from physical damage. Never forget to replace a cassette in its case immediately after use.
• Always keep cassette tapes organised
  Drawers and racks are the best place for a cassette tape collection. They provide protection as well as organisation.
• Equipment must be well maintained
  The equipment on which a cassette tape records and plays is an important part of the team. That's why it must be kept in good working order, free from dust. Regular cleaning of the heads is advisable.

Back-coating

One of the conditions required for a high-quality video tape is that the tape surface must be as smooth as possible. However, a surface that is too smooth will cause the tape to stick against the head drum or guide pins and prevent the tape from running smoothly over the head drum. In addition, an electrostatic charge generated due to mechanical friction causes dust to adhere to the tape surface, dirtying the head. To prevent this, a thin coat of carbon or some other electroconductive material is applied to the back of the tape. Of course, if the surface of this layer is too rough, the magnetic layer will become uneven. So a smooth-surfaced back-coating can lend the tape added strength and improve its runnability, resulting in clearer pictures.

Chroma Output

	Chroma output is a measure of the tape's sensitivity to colour signals. Specifications in a catalogue give a value that is a comparison of playback output of colour signals to that of a reference tape. The higher the value, the higher the colour quality.

Colour S/N

While the sharpness of a picture depends on video S/N, colour S/N expresses the quality of colour reproduction. A high colour S/N produces colour tones of brilliance, purity and freshness. If the colour SIN is low, the colour quality is degraded, resulting in a dull colour picture. In a catalogue, like video S/N, colour S/N is given as a comparison of the tape's colour S/N to that of a reference tape. The higher the value, the richer and more brilliant the colours.

Dropouts

Dropouts are the loss of signals during playback caused by a lack of recorded signals or a momentary tape-to-head separation. When there are dropouts on a video tape, there will be white or black streaks along the scanning lines on the picture screen. Dropouts are caused by scratches on a tape, partial lack of the magnetic layer, or even by adhesion of minute dust particles to the tape surface. Since the performance of even the best video tapes is easily affected by dirt and dust, video tapes must be kept in a dust-free place.

Jitter

	Jitter is a flickering television picture caused by rapid vibrations of a tape. With hi-fi VCRs, audio quality may also deteriorate. Ensuring even tape speed by making the tape surface smooth or applying a back-coating is an effective way to prevent jitter.

Modulation Noise

	"Modulation noise" is a term also used in connection with audio tapes. In the case of video tapes, modulation noise produces not only muddy sound but indistinct pictures with blurred, unclear colours. Modulation noise can be reduced by ensuring stable tape transport with a smoother tape surface and a highly precisioned shell.

RF Output

	RF output indicates the tape's sensitivity to video signals. It shows how accurately the tape can record video signals. Specifications in a catalogue give a value that is a comparison of the playback output of video signals to that of a reference tape. The higher the value, the sharper the picture.

S.S.A. (Specific Surface Area)

	The S.S.A., sometimes called BET, is an indicator of the minuteness of the magnetic particles. It is the total surface area of 1 gram of magnetic particles expressed in m²/g. The larger the S.S.A. value, the finer the magnetic particles. Finer magnetic particles on a tape contribute to less noise and clearer pictures.

Video S/N

The video signal-to-noise ratio (S/N) indicates the difference between the luminance signal level and the noise level of a picture. A high video S/N gives a vivid, fine-textured, crystal-clear picture: the white, very white and the black, very black. The specifications listed in a video tape catalogue give a comparison of the tape's video S/N to that of a reference video tape. 0 dB, for example, means the tape has the same S/N as the reference tape; + 2.0 dB would mean the tape has a video S/N 2.OdB higher than the reference tape, or in other words 1.26 times as high as the reference tape. The higher the value the more vivid and detailed the picture.