Natlock Test Tone Measuring Set: This BMM unit will enable both sending
and
receiving
sites
to
make
accurate
measurements
of
Natlock
communication circuits. Development has reached p.c.b. layout stage.
O.B. Mixer Natlock Control Panel:
An
operator's
control
panel
for
setting up and supervising the operation of the mixer Natlock
comparators. Mechanical format and circuitry finalised and
construction about to begin.
Colour Genlock Unit: Installed in the pulse generator rack this design
will provide full genlock of a programme source without use of a mixer
comparator.
Colour Superlock Regenerators: To provide pulses and subcarrier derived
directly from an incoming video; this unit supercedes a monochrome only
unit and is an economical means of originating superlocked programme
material. The breadboard system has been demonstrated.
DISK REPRODUCTION
Activity has turned from refurbishment to the urgent matter of new
equipment for the future. The emphasis will be on improving audio
quality and providing a range of modular equipment to meet the needs of
all operating departments.
Single Turntable Reproducer:
Theoretical
investigations
have
been
completed and a draft specification issued. Practical work has begun on
the electronics and the unit housing. The Technics SPlO/2 quickstart
turntable and BBC pick-up arm will be used.
Groove Indication: Several forms of transducer, electronic processing
and display have been tested. A choice between optical and electronic
methods will now be made and a design developed for service use.
Testing of Commercial Cartridges: As a result of company failure during
the year, the BBC changed over from Goldring to Shure pick-up
cartridges. As a necessity, this change was based on previous technical
and listening evaluations. However a considered, long-term, choice is
needed and a survey of the most up-to-date cartridges has been made. A
listening panel is to judge those cartridges which have been shortlisted
following quantitative tests. This work is expected to be complete in
time for the new disk reproducer.
MISCELLANEOUS PROJECTS
Broadcasting House Clock-Controlled System
The electronic-clock proposals for automatic control of G.T.S.
distribution, programme selection and transmitter and services start-up
have been finalised and detailed design work will begin early in 1978.
Experimental Microprocessor Work
A real time multiprogramming executive has been written
Texas 9900 microprocessor to be used in all applications
where minicomputers would be considered.
to
up
enab le the
to those
The design of a music synthesiser as a training exercise was completed
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