A method for recording a signal on to magnetic tape. An
aluminum drum, spun by a motor and having at least two
read-write elements placed symetrically around the circumference, is placed along the tape path such that the rotating heads scan the media at a shallow angle to the tape path. A switching system allows more than one
read-write head to scan a swath of tape in a single rotation of the drum. Four head systems are popular since they allow for the reading of a scan immediately following the recording pass and for
oversampling.
Helical scan tape
mechanisms are used most commonly for video and audio recording and data storage. Formats that use the
helical scan method include
VHS,
Beta,
Video-8,
Hi-8,
DAT,
ADAT,
DDS,
Exabyte 8mm, and
AIT.
Compare this method to the
linear head recording technique.