PT 5780 DVB-T Modulator
ProTelevision Technologies
Introduction and Applications
Instruction Manual
Revision 3.11
2-1
2
Introduction and Applications
Designed to meet the most demanding requirements of today’s Digital Terrestrial Television
Broadcast Market, the DVB-T Modulator PT 5780 from ProTelevision Technologies is ranked
number one in its class. A key factor in the products success is the quality of the coding and
modulation process. The unit is furthermore highly flexible and therefore easily tailored to
provide the exact features required in a specific application. This means that you will only have
to pay for the functional features that you need. Retrofitting of features is easy. Normally, the
retrofitting only involves uploading new firmware and software by means of a standard PC.
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2.1
Applications
The performance and flexibility of the PT 5780 allows it to excel in any application related to
DVB-T modulation. Being a DVB-T modulator the core function of the PT 5780 is to modulate
an MPEG-2 transport stream (input) onto a DVB-T compliant COFDM spectrum (output) in
accordance with the rules for channels coding and modulation specified in the DVB-T standard
ETSI EN 300 744.
Basic version
The basic version of the PT 5780 delivers the COFDM spectrum on a user-defined frequency
between 35 and 37 MHz. The default polarity of the spectrum is ‘Inverted’ as normal for a DVB-
T IF signal. However, the user can freely switch the polarity to ‘non-inverted’ if required. The
spectrum bandwidth may be user configured to 8 or 7MHz as required. This flexibility will allow
the user to interface the IF signal to a wide range of transmitters and frequency converters.
The basic unit has two MPEG-2 inputs (ASI format). Switching between the two inputs can be
done manually and automatically. The latter option provides near seamless switching to a
secondary transport stream in case the primary transport stream source fails (a truly valuable
feature for broadcast applications.)
The user can configure the basic version to any transmission mode listed in ETSI EN 300 744
(excluding hierarchical mode and SFN mode.)
Optional features
A broad range of optional features allows tailoring the modulator for the specific application.
If the output COFDM spectrum is required on a frequency not covered by the basic version (35-
37MHz) the
RF Converter option PT 8715
is the answer. This high performance converter
covers the entire frequency range from 30MHz to 1GHz in steps of just 1Hz. The user can freely
set the polarity of the spectrum to inverted or Non-inverted as required. With this converter the
PT 5780 will cover any spectrum application and frequency requirement that you will come
across in the field of DVB-T.
To upgrade the PT 5780 for SFN transmission you will only need to add the
SFN option PT
8732
. This option provides the PT 5780 with market leading SFN performance with respect to
basic timing accuracy and extent of the local delay offset range. Also, even when the SFN
option is installed you can still select MFN mode via the front panel controls. A convenient
feature when conducting pre-testing and alignment of RF parameters on transmitter installations
before the timing references and transport stream with MIP are in place (as a general rule SFN
modulators must mute the output if either of these signals is absent).
Summary of Contents for PT 5780
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