User's Manual Part 1

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antenna and keep it constant over time, by increasing or decreasing the internal gain. In case of faults in the
high-power amplifier stage, the AC stops the AGC in order to prevent any possible damage.
AMPL RS485
In a high-power transmitter there are a number of Amplifier Modules (AM) which RF outputs are combined
in order to provide the required total high power. Although these are separated devices, it is necessary to be
able to control all of them from a single point of the transmitter, and even switch them on and off at the same
time. This point is represented by the AC, which is in constant communication with all AMs through an RS485
serial bus, immune from electromagnetic noise inside the rack of the transmitter. All AMs have to be connected
to the AC by using the proper multi-connector cable to one of the two AMPL RS485 connectors.
+24Vdc
On the rear panel there are two two-poles connectors on which a +24V DC power supply is always available,
protected by a 1A fuse. It is usually used to power supply Dummy Loads in the rack.
RF Monitor
On the front panel of the AC there is a monitor of the RF signal in antenna on a 50Ω BNC connector. The
technical staff of Elettronika provides for the correct calibration of this monitor, taking into consideration the
coupling of the directional coupler and all cable losses, if any. At the nominal power of the transmitter, the
signal level at the RF monitor is 0dBm level.
2.4 CONNECTION WITH A REMOTE CONTROL SYSTEM
The AC can be controlled locally by the display and buttons or remotely by using one of the following three
systems: RS485, Telemeasures or RS232 (only one at a time).
REMOTE CONTROL UNIT
PORT n
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RS485 AMPL
INTERLOCKRS485 REMOTE
GND
ABCDEFGH
AGC TELEMEASURES
FANS CONTROL24Vdc
A
FUSE
FANS1 POWERFANS2 POWERDRIVER POWER
MAIN POWER SUPPLY
RF MONITOR IN
FUSE
A
A
FUSE
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