Elettronika AUTV/250LD, Руководство пользователя

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CONTROL BOARD AND DISPLAY SCH0122BR1
DESCRIPTION
The control board performs all the logic and control fucntions of the amplifier. Both the RF and power supply
parameters are continuously monitored in order to guarantee optimal performance in every working environment:
- amplifier supply voltages Vdc ;
- amplifier supply currents Idc ;
- power module working temperature Temperature ;
- amplifier forward RF power FWD Power .
- amplifier reflected RF power REF Power .
The board is based on a flash microcontroller working at a frequency of 20MHz, able to read the parameters,
control the amplifier and communicate with any PC connected through RS232/RS485 line. Besides, the
microcontroller is programmable, thus it is possible to change the internal program by connecting the appropriate
programmer to the J3 connector and this to a computer. The boards contains a 16 characters x 2 lines display
and two keys to change the parameter currently shown. There are also 3 different LEDs. The green LED
indicates when the amplifier module is ON, the red one is lit when an alarm in occur and the yellow one
indicates the remote control of the amplifier.
OPERATING CONTROL
As indicated in the previous section, the boards is able to read in real time all the necessary parameters to
control the amplifier. When the operator turns the amplifier on the display shows the software release number.
After a few seconds the amplifier is switched on and the first parameter shown on the display is the forward
RF power (“
FWD Power ”).
When a value read is out of the allowed boundaries, the microcontroller activates (after five scans to be
sure) the corresponding alarm indicating this on the first line of the display, and showing on the second line the
physical value. When the alarm is active, the microcontroller switches the amplifier off and restarts the time
counter (3 and 6 seconds). The microcontroller internally stores the number of occurred alarms and if it
reaches 5 the whole equipment is definitively switched off. In this case, if the operator needs to restart the
machine, it is necessary to switch it off and on again (locally o by remote). When the machine is working
normally on the first line shows “TV AMPLIFIER UHF” and the second line shows the parameter with the
format “parameter = xx.x
unit ”. The two keys on the frontal panel allow to change the currently shown
parameter: the left one goes to the next parameter and the right one goes back (in sequence Vdc, Vac,
Temperature, Idc, FWD, REF). If the amplifier is switched off, the “STAND BY” indication is shown on the
display and the backlight is turned off.
The amplifier can be remotely controlled by serial line (contact ELETTRONIKA for details). It is
configurable as RS232 or RS485.