User's Manual Part 1

SWITCH ON PROCEDURE

Before to switch on the Transmitter is extremely important to check:

- The right connections for the RF system (antenna or external combiner) and take greatest care for the Inner

in each coaxial connections;

- the right connections with the Mains Power Supply network, the Neutral line must be present and connected,

and the correspondence with the voltage nominal value request;

- the right working of the earth-ground connections system, for people safety and transmitter right operation;

- the right connections inside the transmitter with input/output RF cable to/from amplifier block and combiner/

divider system, if for transport or installation reason you had disconnected them before.

To follow with first switch on please follow the below indications:

- Set in OFF position all the frontal switch, Main, Amplifier Control and Amplifiers Block;

- turn ON the Mains and the Amplifier’s switch. The Amplifier Control checks the communications with the

amplifier block. If the communication is ok you can turn ON the Amplifier Control, now automatically the

rack’s blowers and the exciter are switched ON;

- give little power in to the amplifier and check if all the indicator are in the right situation (no reflected, no

unbalance on the Amplifier Control, more or less the same indication for current and power for all the

amplifiers block);

- increase the power slowly slowly. At rated maximum output power some watts might be shown as Reflected

Power due to isolation of directional coupler or return loss from antenna system.

EXCITER DESCRIPTION

The ATSC TRANSMITTER is an 8-VSB ATSC professional exciter, designed for the most demanding

digital TV broadcasting applications. It integrates a modulator module with up-to-date FPGA technology and

advanced digital signal processing algorithms in order to generate an absolutely accurate output 8-VSB signal,

with exceptionally optimized modulation and the output filtering techniques.

Very high linearity performances are possible thanks to very careful RF design over the entire VHF and UHF

bands and with an optimal digital precorrection engine working simultaneously in the time and frequency

domains. A high degree of reliability is guaranteed, moreover, by the use of oversized cooling devices and by

control circuits operated by modern microprocessor technologies. The ATSC TRANSMITTER can be used

as a stand-alone 5W RMS transmitter or as a driver stage for amplifiers of greater power. The excellent

spectral purity of the conversion oscillator lets the ATSC TRANSMITTER radiate an 8-VSB signal with an

excellent MER value. The ATSC TRANSMITTER is equipped with a powerful ASI/SMPTE inputs management

block which allows to manage the Transport Stream (TS) inputs in a fully redundant configuration, thus

significantly improving the reliability of the whole broadcasting system in every operating condition.

The ATSC TRANSMITTER is totally compliant to the A/53, A/54 and A/64 ATSC recommendations with

6MHz output channel bandwidth, in VHF and UHF bands.