c. The longitudinal tape speed is 7.5 inches-per-second (ips) and the width
is normally 1/2 inch. One-inch tape is also used. This standard applies only to
open reel-to-reel video recorders.
Due to their specialized recording format,
helical scan recorders require a relatively high writing (head to tape) speed.
(Writing speed is the term used to describe the electronic impulses laid on the
video tape.)
d. The exact speed will depend on the machine configuration and the width of
the tape used. With single-head systems, the writing speed is approximately two-
thirds of the single-head speed.
2.
Helical scan means "in a spiral formation," a line around a cylinder at an
angle other than parallel with the axis.
Thus, we gain a mental picture of the
tape path around the head assembly of the helical scan recorder/ producer (fig 1-
1).
Figure 1-1.
Helical scan videotape transport
3.
The basic design features for helical scan videotape magnetic recorders must
satisfy the requirements of a very large market.
They must have a frequency
response wide enough to handle the standard television signal, specialized closed-
circuit video, high-bit-rate digital, radar-type signals, and high frequency type
signals, and high frequency pulse code modulation (PCM).
They must be portable
enough to provide easy handling. They must also be simple enough to operate with a
minimum amount of maintenance.
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