b1gh level sender is being developed, with l2dB gain and with an output
capability of +12dB relative to 1 volt, also on BMM chassis.
Tone Switching_System
A tone system for remote switching over sound programme circuits is
being developed on the BMM chassis system. The first part, which uses
two tones at any of 10 frequencies between 6.6kHz and l6.8kHz, is also
compatible with the existing tone switching equipment. A further
development consists of a PSK modem which will considerably extend the
number of switching functions available.
Ceefax Decoder
A one volt video input Ceefax decoder providing either an RGB or
monochrome output is being developed. This unit, which employs a Tifax
module, comprises a small portable box, together with a remote keypad
for control and will be used for general monitoring applications.
Signal_Processing_Equipment for External Broadcasting
A modification of the AM6/l6 variable-emphasis limiter is being
developed to provide compression for External Broadcasting signals.
This development followed a demonstration by Research Department which
indicated that the subjective effect of such a system would be better
than that resulting from normal compression. A line dispersion
simulator is included in the equipment.
Analogue to Digital_Converter for the Automatic Fault Reporter
This sub-unit scans several analogue voltage inputs and produces digital
signals representing those volt ages. Hence information from an
automatic monitor, including details of parameter values, can be sent
over the public telephone network to a remote point.
Telephone Control and Balance Unit
This development is intended to provide a universal interface between
BBC equipment and the Post Office public telephone network. The basic
unit will be contained in a portable box, but a variation will contain
additional facilities such as "agc"
and
"voice-over"
as
required for
"phone-in" programmes.
Communication System for Television O.B.'s
Following a feasibility study which took place last year, a breadboard
system is being designed which will provide multiplexed video and
communication channels on a single cable. This will be given a field
trial and assuming that a satisfactory performance can be achieved the
final design will be implemented.
Microprocessor Applications
A familiarisation exercise has been started into the subject of
microprocessors. One particular application which is being investigated
is for statistical analysis of automatically measured parameters.
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