In spite of the urgency of this modernisation programme we hope to use
the opportunity to raise the quality of the audio output. The main
improvements which can be realised relate to reducing extraneous noise
and spurious modulation from the turntable transport and achieving
higher fidelity from the pick-up cartridge.
The Department's concern that microprocessors should be properly and
effectively used in new designs has led to the involvement of the
Computer Applications Engineer in many discussions and meetings to
resolve new or unusual problems. Advice and assistance with specific
designs using microprocessors covering choice of hardware and methods of
software development has now become a regular part of his work.
Additionally the facilities available for Computer Aided Design have
become fully stretched and he has spent some time reviewing modern
equipment and advising management on future purchases.
The three time-sharing O.B. mixer comparator cards are now fully
compatible and the Line-drop unit, the last to be designed, will enter
production next year. Thus all future O.B. mixers, starting with the
new London based CMCRs, can be fitted for the faster rates of source
Natlock Test Cards
The O.B. mixer Natlock test cards have been updated and it is now
possible to do test jig alignment of the three comparators
simultaneously by simulating full system operation on the test bench.
Source Synchronising Equipment Manufacture
Pre-production quantities of Sync pulse generators, Master drive
equipment and Video sync timing meters have been manufactured for
operational departments and will be in use next year.
ENG Station Synchronisation
An experimental synchronising unit coupled to a
generator has been supplied as part of the ENG
enables the base-station timing-corrector to quickly
error of a few microseconds in the incoming signal.
be applied prior to re-recording.
slave Sync pulse
field trial. This
adjust itself to an
Correction can then
New Digital Applications
The possible use of digital synchronisers in the BBC has led to
discussion with manufacturers and to detailed evaluation of the Quantel
equipment. The desirable features of a synchroniser for BBC use have
been considered in collaboration with Research Department. The line
synchroniser version of the digital timing corrector is in regular
programme use and we have been asked to make a second unit for O.B.'s.
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