~~ Modular Unit8
Up-dated versions of many
BMM chassis units now that
standard studio functions are required using
this system is specified for the majority of
A BMM version of the general-purpose studio compressor/limiter mentioned
above is being produced for Local Radio which only provides a selection
of the simpler functions of which the circuitry is capable. Other
designs have been for a microphone amplifier, a line-up tone generator
and a voice-over unit.
The major activity on new assemblies has been assistance to Equipment
Department with the first production batch of new Outside Broadcast
monitoring loudspeakers, the LS3/7. The late change in high frequency
unit type required extensive work on specifying the new unit. However
close co-operation resulted in the production of the first batch of
LS3/7's on schedule and with fewer problems than might be anticipated
with a new design.
Co-operation has continued with Equipment Department in the production
of the necessary tooling and expertise to enable the in-house production
of the standard BBC 300mm drive unit. Various possible improvements for
higher power voice coil working have been assessed and alternative
plastic surround materials investigated.
Regional__Continui ty Desks
Following consultation with Radio Projects and other interested parties,
laboratory work has started in earnest for a new series of stereo
continuity desks for use in the national regions and in London. In
addition to the normal continuity function of linking programmes, they
originated programmes. The development of these desks, which is being
carried out jointly with SCPD, will form a major part of the Section's
work over the next two years.
Intercom Amplifiers (AM5/20, AM5/2l)
These two amplifiers will be used to drive loudspeakers in intercom and
talkback systems, replacing an ancient design which was very widely
used. They can be powered from any of the currently used d.c. power
systems and will provide up to 2 watts output as supplied, or up to 10
watts with an additional heat sink. The basic card provides 40dB of
gain, while the 2U-BMM version can be incorporated in a module system
with options of gain control, input attenuation and balanced input.
Studio Compressor/Limit er (AM6/17)
This "knock-down" version is supplied loose to commercial manufacturers
to incorporate into their own modular desk system. A selection of
compression laws is provided a8 well as preset and auto recovery times.
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