Two of the
operation.
compressors can be ganged together
A voice-over terminal is provided.
to
provide
stereo
Microphone Amplifier (AM9/l9, AM9/l9A)
A 2U-BMM microphone amplifier with panel-switched gain control. It is
intended for areas such as Local Radio stations and television
continuities. One version provides sharp rejection of the 625-1ine
television scan frequency.
Radio Broadcasting Presenter - Operated Studio Desk (DK4/25)
Following six months of operational use of the Designs Department built
desks at the Orkney and Shetland studios, the Section has completed a
major rebuilding of the desks on site to provide continuous fader
control of the local microphone levels and a revised a.g.c./1imiter
characteristic. Although the operation is now less automatic, the desks
are now better suited to the more elaborate programme material which is
being originated.
Outside Broadcast Monitoring Loudspeaker (LS3/7)
Completed manufacturing information has been supplied to
Department. The first production batch of 30 started delivery
A further batch of 50 is in production and orders for 100 more
placed.
Equipment
in July.
are being
Line-up Tone Generator (OS2/52)
This BMM oscillator replaces several previous oscillators and
900Hz line-up tone with a close long term tolerance (0.2dB)
output level.
provides
on the
Voice-over Unit (UN4/6)
This BMM modular unit provides programme path gain reduction for use in
the next generation of Local Radio stations.
PROJECTS IN PROGRESS
Transmitter Protection Limiting Amplifier (AM6/18)
A special purpose limiting amplifier to be used in large quantities as
part of the LF/MF reorganisation. Remote selection of compression is
provided from external switching, and the gain recovery is chosen for
medium wave transmission conditions. The unit also contains a bandpass
filter to limit the modulation spectrum and notch filters to remove
signalling tones used on the programme circuit.
Studio Compression/Limiter (AMB/2l)
The "knock-down" compressor/limiter mentioned above but mounted in a BMM
module for Local Radio use. Only simple functions are made available.
External Broadcasting General Purpose Desk (DK4/23)
Progress
modules.
on
this
desk
has
been
1 imi ted to the design of
some
new
The delivery time scale is still very long, and proposals for
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