T.E.M. A07B500S, Руководство пользователя, Страница: 12 / 131

A07B500S manual
Pag. 12
Besides the keyboard, the transmitter can be remotely controlled in different ways. A
personal computer can be connected as monitor to the DB9 socket placed on the front panel and by
a special program, to be load easily on the PC, all the transmitter parameters can be set and seen.
Furthermore it’s possible to perform all the modulation analysis provided by the CEPT 54-01
regulations and create the related graphics which can be stored as a file in the PC.
A second RS232 port placed in the transmitter rear part can be connected to the power
amplifier connected in series to the exciter, thus allowing the power data display on the same PC
connected to the front RS232.
A third RS485 port placed in the rear part can be connected to a MODEM which is
connected to the phone line thus assuring the transmitter telecontrol, remotely or from the studio.
The same RS485 port can be used for the connection N+1 of more transmitters (max 16). In
this case a transmitter acts as a “joker”, so it replaces the faulty equipment, automatically adapting
to all its parameters. Each transmitter is also provided with an output port (IN/OUT) suitable to
drive the antenna cable multiplexer and the one for the input audio signals switching.
3.2 Available options
a) STEREO ENCODER : additional board allowing the internal encoding of the
stereophonic signal
b) AGC : additional board allowing a frequency modulation
control
c1)
REMOTE CONTROL : software for the PC or GSM connection
c2)
N+1 system : software to obtain N+1 system
c3)
1+1 system : software to obtain 1+1 system
d)
Line Voltage : 115 Vac
Model A07B500S-S have 10 Khz frequency steps
3.3 Block diagram
The transmitter can be modulated by five different audio signal.
The first two ones are made by monophonic left and right channels, which can be balanced
or unbalanced. The input dynamic goes from –6 to +12dBm with an input impedance which can be
high or low. On these channels either the European or American pre-emphasis value can be
inserted. A low pass filter on each of the two inputs assures a good attenuation of audio frequencies
higher than 15KHz which could interfere, in case of stereophonic transmission, with higher band
and with la subcarrier of the Multiplex signal; the out-of-band attenuation of the filter is not
excessive in order not to increase then phase distortion (group delay) of the in band audio signal: