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<h1>Welcome to Audio - Design and manufacture broadcast quality radio microphone systems.</h1>
<h2>Audio Ltd design and manufacture broadcast quality radio microphone systems for use in film and television.</h2>
<h3><b>wireless microphone, radio microphone, uhf systems, frequency agile transmitter,
frequency agile receiver, diversity system, body pack transmitter, location
sound</b></h3>
<p><b><a href="index.htm">wireless microphone</a>, <a href="audio.htm">radio microphone</a>,
<a href="sound.htm">uhf systems</a>, <a href="wireless.htm">frequency agile
transmitter</a>, <a href="pages/accs.htm">frequency agile receiver</a>, <a href="pages/dist.htm">diversity
system</a>, <a href="pages/hxir_detail.htm">body pack transmitter</a>, <a href="pages/index1.htm">location
sound</a></b></p>
<p>Audio design their <b><a href="pages/products.htm">location sound</a></b> systems
to be flexible. A <b><a href="pages/products1.htm">audio ltd</a>, <a href="pages/store.htm">wireless
microphone</a></b> comprehensive range of accessories is available to help you
fit your Audios into the way you work. We offer a large range of connecting
cables to allow you to power your kit from <b><a href="pages/store1.htm">frequency
agile receiver</a></b> mixers, <b><a href="pages/tech_spec.htm">diversity system</a>,
<a href="pages/tech_spec1.htm">body pack transmitter</a></b> cameras, external
<b><a href="pages/vdb_poles_detail.htm">radio microphone</a>, uhf systems</b>
sources. The 4 way and 2 way racks allow you to house your receivers to
suit the job you are <b>frequency agile transmitter</b> working on.</p>
<p>To obtain maximum range we can <b>frequency agile transmitter</b> offer various
antennae including Yagis and for when you can't avoid long <b>frequency
agile receiver</b> antenna cable runs, Mast Head <b>diversity system,
body pack transmitter</b> amplifiers which power from the DK2000.</p>
<p>If there is something you need for your wireless <b>audio ltd, wireless
microphone</b> kit please ask. If we don’t have it, maybe we should have.
In addition <b>location sound</b>most of our distributors are enthusiastic sound
people themselves. They have all kinds of accessories for mounting Audios
on mixers, <b>frequency agile receiver</b> cameras and other <b>radio microphone,
uhf systems</b> special accessories to suit their market. Otherwise perhaps
we can make it for you.
<p>Radio Waves are electromagnetic <b>audio ltd, wireless microphone</b> radiation,
the same as Light and just as with light, areas can fall into shadow, particularly
where there are metal objects which can <b>radio microphone, uhf systems</b>
reflect and absorb RF energy. But more importantly and in common with
<b>frequency agile transmitter</b> the other wave propagated medium we are all
familiar with, Sound, radio waves suffer from constructive and destructive interference,
or phase cancellation. This can mean that even in a location of <b>frequency
agile receiver</b> relatively high signal <b>diversity system, body pack transmitter</b>
strength loss of signal can still <b>radio microphone, uhf systems</b> occur.
Where the transmitter or receiver or other RF reflecting objects are moving
then phase cancellations can come and go <b>location sound</b> very quickly
causing the all too familiar burst of <b>radio microphone, uhf systems</b> noise
or dropout.
<p>There are actually <b>frequency agile transmitter</b> two basic types of diversity
applied to radio reception: Frequency diversity and Spacial diversity.
In both cases the aim is to provide different numbers of whole <b>audio ltd,
wireless microphone</b> wavelengths from the transmitter to the receiver <b>diversity
system, body pack transmitter</b> antenna, or even physically <b>radio microphone,
uhf systems</b> different paths.</p>
<p>Frequency diversity which was used on HF <b>radio microphone, uhf systems</b>
transmissions achieved this by transmitting the same signal on two or <b>location
sound</b> more different frequencies. Any reflections from the ionosphere
<b>diversity system, body pack transmitter</b> causing phase <b>radio microphone,
uhf systems</b> cancellation on one frequency would have <b>frequency agile
transmitter</b> different phase on the other frequency and therefore not <b>audio
ltd, wireless microphone</b> cancel. Widely different frequencies <b>frequency
agile receiver</b> will also take a different path completely and suffer from
a quite different set of losses and reflections.</p>
<p>Spacial diversity <b>diversity system, body pack transmitter</b> traditionally
used two antennae and two <b>frequency agile transmitter</b> receivers at the
receiving end. Providing the antennae were far enough apart to ensure
that a different combination of phases of signals were present on each, then
phase cancellation occurring <b>frequency agile receiver</b> at the receiving
end could be eliminated. This <b>location sound</b> however was of less
use against cancellations which had occurred far away in the ionospheric <b>radio
microphone, uhf systems</b> disturbances of the signals. It is <b>audio
ltd, wireless microphone</b> clear that this system can only work if the antennae
are a good proportion of a wavelength apart.</p>
<p>The situation is quite different for VHF and UHF radio mics. Here we
are not concerned with strange distortions of the signals by the upper atmosphere.
The main <b>frequency agile receiver</b> problem is simple reflection.
RF energy bounces around the <b>diversity system, body pack transmitter</b>
rooms and streets where a recordist needs to work. This can mean that
phase cancellation is a major problem in any built <b>location sound</b> up
environment. However, when electromagnetic signals reflect they change
their <b>radio microphone, uhf systems</b> polarisation. This is why polarising
sunglasses reduce reflected glare. It also <b>radio microphone, uhf systems</b>
means that the mix of signals appearing at the receiver antenna are not simply
polarised in the same plane as the transmitting antenna. Audio Ltd. recognised
that this <b>audio ltd, wireless microphone</b> means that the traditional received
wisdom <b>frequency agile transmitter</b> that antennae must be at least a wavelength
apart for diversity to work is no longer valid for radio mics. In fact
polarisation <b>diversity system, body pack transmitter</b> diversity works
exceptionally well with Audio’s Dx2020 and Dx2000 receivers.</p>
<p>Diversity is not however an excuse for making insensitive receivers.
There are also shortcut ways of achieving some of the benefits of diversity
<b>location sound</b> reception. For example simply having two <b>radio
microphone, uhf systems</b> antennae and switching to the other one as soon
as the signal gets weak or drops sharply on one, hoping that the signal will
be better on the other, is a system which has been practiced by <b>frequency
agile receiver</b> some exponents. There are a number of problems, one
in particular, with this scheme which we won’t detail here. Audio took
the approach of taking the <b>frequency agile transmitter</b> same full receiver
design with full sensitivity and selectivity, and then duplicating it.
Careful monitoring of RF level over a huge dynamic range <b>audio ltd, wireless
microphone</b> which is individually tracked on each unit means that the receiver
can never switch to a worse signal. A noiseless switching circuit was
developed to take full <b>radio microphone, uhf systems</b> advantage of the
<b>location sound</b> accurate level detection and allow <b>diversity system,
body pack transmitter</b> switching as often as needed without noise or clicks.</p>
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