Technical Description - WisyCom MCR 41 Instruction Manual

high performances microphone system
t
echnical description
The MCR42 is a professional dual true diversity receiver for wireless microphones reception especially de-
signed for broadcast production, live stages, theatres and top professional applications.
It's winning performances are:
• High immunity on strong RF environment
• Huge switching bandwidth
• High audio performances and flexibility with analog or digital processors
• High reliability and durability
A
B
MCR42: main block diagram
One of the milestones in the design of the MCR42 is
high reliability: most of the circuitry of the receiver
is independent one from each other.
Above a schematic with an overview of main receiv-
er functions.
For each antenna the RF signal is split in the receiver
1 and in the receiver 2 (antenna A and antenna B)
with a wide band splitter. In this way any one receiv-
er could be tuned in any frequency of the switching
range (typ. 240 MHz).
Receiver 1 and 2 are diversity receivers: each one is
made of two receivers tuned on the same frequency,
hereafter called section A and section B.
ceiver 1 section A and the receiver 2 section A are
connected to the antenna A, the receiver 1 section
B and the receiver 2 section B are connected at the
antenna B.
Each receiver has its own demodulated signal and
its own RSSI signal (Receiver Signal Strength Indi-
cation); a DSP selects or combines signals from
section A & B to have the best audio.
The demodulated signal flows to the digital audio
processor.
Receiver - 1- A
Receiver - 1- B
Receiver - 2- A
Receiver - 2- B
Front panel
The re-
Receiver supervisor
microcontroller
and user interface
Data signalling detection and demodulation:
the data sub carrier is digitally filtered to a very se-
lective equivalent bandwidth (3Hz). Each filter has
its own data demodulator, one for medium speed
data detection at the output of the first filter and one
at low speed data detection at the output of the sec-
ond filter. All the two demodulators are connected to
the supervisor micro controller for the data battery
detection and signalling.
Digital audio processor: the demodulated signal
is filtered by an anti aliasing low pass filter and then
converted in the digital domain with a 96KHz 24bit
audio A/D converter.
(DSP), working in double precision, replicates all the
analog functions with very high accuracy, ultra low
distortion and without typical analog problems like
components tolerances or long term drifts or tem-
perature drifts etc. The high speed audio algorithms
implemented in assembler into the MCR42 maintains
the audio delay at about 1.3 milliseconds, making
it ideally for live events and to keep audio delay as
short as possible. The DSP unit also filters and de-
modulates the data carrier and communicates all the
parameters and informations to the supervisor micro
controller. The audio output goes to the digital out-
puts (AES3) or is converted in the analog domain
with a high quality 24 bits 96KHz D/A converter and
an anti-aliasing filter.
Line 1
Line 2
AES3 Output
Line 1 & 2
Com Rx 1
Com Rx 2
Ear-ph Left
Ear-ph Right
INFRARED
SERIAL LINK
The digital signal processor
Pag. 5