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User Manual
Rev. 1.1 - 04/07/12
SDC200/RDS
ELETTRONICA
Two major features of
SDC200/RDS
are compact design and userfriendliness.
Design is based on a modular concept: the different functions are performed
by modules that, for the most part, are connected through male and facilitates
maintenance and module replacement.
This Stereo Coder uses a frequency sinthesized internal digital circuitry that allows
very linear modulation, high stereo separation, high input level capability.
The input/output analog section of good quality integrates oneself with digital
system answering for high input dynamics, high signal/noise rate and very low
distorsion.
4.2.1 RDS System Description
The Radio-Data-System is proper for the transmission of information in mono/
stereo programs of VHF/MF (87.5-108 Mhz).
It satisfies the requested requirements to the transmission of supplementary data
on radio programs:
1) Compatibility with the current mono/stereo transmissions;
2) Absence of interferences towards the adjacent programs;
3) Compatibility with other identification systems which are already working.
The system, selected by an international specialistic team, allows the data
transmission at a speed of 1187.5 bit/sec with phase modulation at two levels ,
carrier wave 57 Mhz and range ±2 Khz.
The broadcasted binary signal is in advance put out on a differential
codification.
The registry of transmission is at packages of lenght 104 bits (87.6 ms) named
GROUPS, each of them composed of 4 blocks of 26 bits.
Every block is composed of 16 bits of information and of 10 bits of protection, which
are properly studied to allow the recovery of an erroneous word with a maximum
of 5 wrong bits.
They are provided with 16 separete blocks of which 6 are still not defined; every
group begins with a PI identification code (Program Identification) which has
the double intent to synchronize the receiver and to identify the channel which
transmits the signal.
The pourpose of the encoder
SDC200/RDS
is to manage the principal services
defined by the standard CENELEC EN 50067 as: PI, PS, PTY, TP, AF, TA, DI, M/S,
PIN, RT, EON, TDC, IH, CT.