chain of relay stations,
cumulative effects.
these errors can produce unacceptable
Television Re-broadcast Receivers
The present generation of UHF receivers have been substantially modified
to
deal
with
component
obsolescence
and
changed
operational
requirements. The modification programme will affect some 300 units in
the field.
Television Feasibility Studies
A number
acquire
embrace
class AB
of feasibility studies have been carried out in order to
a working knowledge of new components and techniques. These
systems for UHF synthesisers, new UHF power transistors and
operation at UHF.
PROJECTS IN PROGRESS
Sound Radio Link
Following the development of a radio link working around 460MHz for
local radio, a similar link has been developed for use by Communications
Department and Tel. O.B.'s The latter link has additional facilities
and can be used in conjunction with multiplex equipment to provide a
number of channels (up to five) over a single link. When used in the
basic single channel mode, the equipment provides a high quality music
channel.
Band 11 Receivers
A new fixed frequency Band 11 receiver has been developed to replace the
existing design. Particular attention has been paid to the RF stage to
produce a receiver with a low noise figure and a high cross modulation
performance. The overall performance of this receiver is such that its
design should remain current for many years. The RF and IF stages are
expected to be incorporated in the design of the new Band I I transposer.
Band 11 Transmitter Drive
A replacement drive is in hand as part of the overall re-engineering of
Band 11 equipment. It will have a power output of 15 watts (maximum);
the output stages will also be used by the new Band 11 transposer.
Band 11 Power Amplifier
There is now a requirement of a substantial number of 500W and lkW solid
state amplifiers. As an interim measure an existing range of amplifiers
has been updated and a limited number are to be made. It is expected
that a new higher power module will be produced next year.
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