using paper tape as a data storage medium has proved successful; and a
number of automatic Tarif units have shown on field trials that where
large
or
last-minute
changes
are
necessary
they
make
a
useful
contribution to easy operation.
The system is thus well established but many designs, some of them very
old, are in the field. The Section has begun the re-design of all these
units, exploiting modern devices and pruning facilities where possible.
Only one type of processor will be used by the various control systems,
manual, automatic and pre-programmed will be integrated so that manual
trim and override control is available. The estimate is that a
microprocessor will be sufficiently powerful to do this.
Sound Recording
The many hundreds of professional audio tape recorders in service in the
BBC and the 500,000 spent on new audio-tape each year indicate the
importance of this work. Principal jobs in 1977 were new machine
appraisals, the design of tape reclamation equipment, the provision of
reference test tapes and the design of accurate test-tape copying
equipment.
At the moment tape reclamation supplies about 20% of the BBC's
requirements. it helps to reduce the quantity that has to be held in
buffer stocks and it provides an emergency source of tape should the
supply fail. An essential feature of tape reclamation is technical
inspection to ensure that old tape can be used with confidence. The
technical problems are severe. involving the detection of minute
blemishes whilst running the tape at over seven times normal speed. A
new, automated tape-reclamation equipment is being designed; twenty new
reclamation units are required in 1978 to replace worn-out units and
increase throughput.
Test tape production must always be at a very high level to keep pace
with
consumption.
The
determination
from
first
principles
of
a
correctly recorded test tape requires dedicated machines and special
head mountings to handle tape widths from 6mm to 50mm at speeds from
39cm/sec down to 10cm/sec. The Section is equipping two special tape
decks to handle this range of tape width and speed.
PROJECTS COMPLETED
Automatic Azimuth Control for Cartridge Tape Recorders
The prototype equipment has proved successful but due to the pressure of
other work we cannot complete the project. Radio Broadcasting
Department have agreed to make a number of these equipments using the
prototype as a model.
Automatic Test-Tape Makers
An 8-channel equipment has been made for
2-channel equipment for Film Department, so
tapes with up to 8 tracks per tape can be
effort.
Radio Broadcasting and a
that test films and test
made with relatively little
A Tarif Pre-programmer for the Television Service
A third set of equipment has been delivered to Television Centre. The
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