Eletronika AUTV/1500LD User manual

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LDMOS - UHF TV AMPLIFIER
AUTV/1500LD
Users manual

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_______________________________________________________________________________________________
Section 1 - Information
Contents:
1.1 Description
1.2 Technical characteristics

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1.1 DESCRIPTION
The AUTV/1500LD is an amplifier operating into Band IV-V for common amplification process of the Vision
and Sound carriers.
The amplifier has been designed to offer to the customer high performances, high reliability and greater
simplicity in his operation and maintenance procedures.
The amplifiers modules employ all solid state LDMOS technology in order to obtain high gain, wide-
band performances, very good linearity, reliability and high efficiency.
The equipment design allows the soft degradation (RF power loss) for several transistor faulty: in fact the
output combiner uses RF power resistors for unbalancing power dissipation. The unit is enclosed in a cabinet
for 19- 6U rackmounting.
AUTV/1500LD
LDMOS - UHF TV AMPLIFIER

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1.2 TECHNICAL CHARACTERISTICS
RF
Frequency range 470 - 860MHz
Output power 1300W PEP
Video/Sound power ratio 10/1
Out stage technology Solid State LDMOS
Vision-Sound amplification Common
I.M.D. (-8, -10, -16dB) Better than -54dB
Standards G,K,N
Spurious and harmonics level In compliance with CCIR rec.
RF Output impedance 50W
RF Output connector 7/16
GENERAL
Power supply 230Vac, ±10%, 50/60Hz
400Vac 3P+N (on request)
Power consumption 3400VA at black level
RS232 Socket DB9 Connector (on front panel)
RS485 Socket DB9 Connector (on rear panel)
Telemeasuring socket DB9 Connector (on rear panel)
AGC Socket DB9 Connector (on rear panel)
Power factor > = 0.9
Ambient temperature -5° to +45°C
Relative humidity 20% - 90%
Altitude Up to 2.500 meters
Cooling Forced air
Cabinet Rack 19-6U
Dimensions 760x263x266mm
Weight 70kg
PROTECTION THR.
FWD Power 1500W
REF Power 150W
Unbalacing 350W
Temperature 75°C
IDC 25A
VDC Min 10V - Max 33,5V

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_______________________________________________________________________________________________
Section 2 - Installation
Contents:
2.1 Operating environment
2.2 Preliminary operations
2.3 Telemeasuring socket connections
2.4 RS232, RS485 and AGC socket connections
2.5 Preventive maintenance
- Front panel
- Rear panel

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2.1 OPERATING ENVIRONMENT
You can install the apparatus in a standard component rack or on a suitable surface such as a bench or desk.
In any case, the area should be as clean and well-ventilated as possible. Always allow for at least 2 cm of
clearance under the unit for ventilation. If you set the apparatus on a flat surface, install spacers on the bottom
cover plate. If you install the apparatus in a rack, provide adequate clearance above and below. Do not locate
the apparatus directly above a hot piece of equipment.
2.2 PRELIMINARY OPERATIONS
Correct installation of the equipment is important for maximum performance and reliability. Antenna and earth
connections must be installed with the greatest care. The equipment adjustment isnt need, because the unit is
completely adjusted by our technical staff. This is the installation procedure:
1. connect the power supply cable of the exciter to the auxiliary socket on the rear panel of the amplifier;
2. connect the power supply cable of the amplifier to the electric network (230VAC). If there is the Isolator
Transformer, the amplifier is provided with cable and plug;
3. connect the exciter / antenna cables respectively to the RF IN and RF OUT on the rear panel of the
amplifier.
WARNING!!!
FOR ELECTRICAL SAFETY REASONS AND IN ORDER TO KEEP
THE APPARATUS SAFE, THE GROUND TERMINAL OF THE
APPARATUS MUST BE CONNECTED TO THE EXISTING GROUND-
ING SYSTEM AND NOT BY USING THE SHIELD OF THE OUTPUT
COAXIAL CABLE.
13
2
Three-Phase cabling
Monophase cabling

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When the apparatus is put within a combined system it is directly connected to the input splitting and output
combining systems.
Before fully powering the apparatus, check that the output connections of the coaxial cable to the antenna
system are working.
In order to this it is possible to check the indication of the reflected power at low power levels. Only if the
SWR indication on the display is 0, the output power can be slowly increased. At maximum output power,
some watts might be shown as reflected power.
2.3 TELEMEASURING SOCKET CONNECTIONS
DB9 Socket
2.4 RS232, RS485 AND AGC SOCKET CONNECTIONS
PIN N° SIGNAL TYPE IN / OUT FUNCTION
1 Analog Output FWD Power
2 Analog Output REF Power
3 Digital Output Temperature
4 Digital Input Interlock
5GND - -
6 - 7 Digital Output Free contact (closed when alarm)
8 Digital Input 0V = ON
5V = Normal
9 Digital Input 0V = OFF
5V = Normal
PIN 123456789
FUNCTIONS -TxDRxD-GND----
RS232 - DB9 Socket
PIN 123456789
FUNCTIONS -Rx-Rx+5VGND-Tx-Tx+-
RS485 - DB9 Socket

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AGC - DB9 Socket
PIN N° SIGNAL TYPE IN / OUT FUNCTION
1GND - -
2 Digital Output 0V = Normal
5V = AGC Alarm
3 Digital Output 0V = Normal
5V = AGC Alarm
8 Analog Output FWD Power
9 Analog Output FWD Power
2.5 PREVENTIVE MAINTENANCE
To ensure maximum performance and minimum repair trouble, we strongly recommend you to follow the
below stated headlines for preventive maintenance:
1. check antenna installation and ground connection at regular intervals;
2. keep your apparatus clean and dry externally: this will ensure continuous functioning of the front panel
controls;
3. if the apparatus has not been used for a long period of time combined with exposure to extreme environ-
mental conditions, open the unit and make a visual inspection.
Remove salt, water or ice with a moist cloth before turning the apparatus on. Check that the cooling fans are
running freely.
4. for general maintenance and top performance, call an authorized service technician to give the apparatus
and the complete antenna/earth connection installation a general check every 12-18 months;
5. check at regular intervals that the air intake located on the front panel is free of dust. If there is visible dust,
remove it by means of a soft brush.

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Front panel
1
2
3
4 5
6
DESCRIPTION
1 LCD Display
2 Function keys
3StatusLEDs
4 RF Monitor connector
5 Main switch
6 RS232 Socket

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Rear panel
1
2
3
4
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9
8
7
DESCRIPTION
1 Breaker
2 Power supply socket
3 Auxiliary socket
4Fuse
5 RS485 Socket
6AGCSocket
7 Telemeasure socket
8 RF Input connector
9 RF Output connector

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_______________________________________________________________________________________________
Section 3 - Operation
Contents:
3.1 Operation
3.2 Display
3.3 Menus

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3.1 OPERATION
At startup, after initial image, the display shows the main screen with the RF powers as in Figure 1:
The user may turn on and off the amplifier by means of the switch on the front panel. The control board turns
on all the power supplies, the exciter (if any), and internal cooling fans. While the amplifier is working, the
micro-controller monitors continuously the most important parameters: power supply voltages, absorbed
currents, high power zone temperature, forward and reflected powers, unbalances (if any). Each measure is
associated to a maximum threshold beyond which the amplifier is immediately put in protection status by
turning off one or more power supply, depending on the failed block. In order to prevent a temporary problem
to trigger a definitive protection status, the failed block is turned on again, after some seconds, for up to five
times. If it goes beyond the protection threshold for more than five times, it is declared as FAILED and it will
no longer be turned on. In this case, the amplifier will have to be turned off manually by means of the switch on
the front panel, then turned on again after performing the needed maintenance.
On the front panel there are also three LEDs labelled ON, REMOTE and ALARM. Their meanings are
explained in Table 1.
Figure 1: Main screen
Table 1: Meanings of the three LEDs on the front panel
1Screenshots in this manual are indicative, so they can be different from those on your equipment.
LED COLOUR MEANING MEANING WHEN BLINKING
ON Green The amplifier is on
The amplifier has been turned on
locally but it has been turned off by
remote
REMOTE Yellow Remote control is
enabled It neve r b link s
ALARM Red An alarm is present It never blinks

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3.2 DISPLAY
The control board is provided with a modern pixels graphic display with blue background. Normally it always
shows a title bar (on the top line) and a status bar (on the bottom line).
The title bar, see Figure 2, shows the name of the amplifier (TV Amplifier) and the current time. If the amplifier
is a single unit coupled externally with other units in a high power transmitter, the title bar shows the amplifier
number (slave address) too.
Figure 2: Title bar
Figure 3: Status Bar
The status bar (Figure 3) indicates the forward and reflected powers and the temperature. It also contains two
symbols for the interlock (lock) and the alarm (bell).
The bell symbol is continuously displayed in case of alarm. It blinks if there has been an alarm which has ended
but has not yet been seen by the user. It stops blinking once the Log has been checked.
The interlock symbol is displayed only when this function is enabled. It may be either a close lock, as in Figure
3, when there is no alarm (interlock chain closed) or an open lock in case of alarm (interlock chain open).
Since the status bar is always showed on the display, regardless of the screen, the user may monitor at any
time the most important parameters and the presence of alarms while moving between different screens.
3.3 MENUS
The user may see or modify locally some configuration parameters using the four buttons on the front panel.
All screens areorganized in a hierarchical menus and the user may move between them in a simple and intuitive
way.
To see the menu its sufficient to press the ESC key (see Figure 4).

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Figure 4: Main menu
The display only shows three items at a time: all the items can be scrolled by the UP and DOWN arrow keys.
Any item can be chosen by selecting it and pressing the RET key. Menu entries with an arrow on the right
open sub-menus when chosen. Thus there is a hierarchical structure as in Figure 5. To go back from a sub-
menu to the previous menu, press the ESC key. If the ESC key is pressed in the main menu, the RF powers
screen is accessed.
Figure 5: Hierarchical menu structure
All menu items are described in detail below.

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- RF Powers
This is the main screen showing the RF powers of the amplifier: forward power, reflected power, unbalances,
if any. For forward power a level bar is displayed. See an example in Figure 1.
- Power Supply
This screen shows all the signals coming from the power supply. To check the next (previous) power supply
press the UP (DOWN) key. For each power supply, the two voltages, the two absorbed currents and the
status (ON or OFF) are shown.
Figure 6: Power supply screen
- Log/Alarms
The control board is provided with an external EEPROM and a clock. Any alarm or switching event with the
time at which it occurred is saved in the EEPROM. The Log/Alarms sub-menu allows to manage this log.
It is possible to see the events stored in the log by selecting Log/Alarms View Log/Alarms. All events
can be scrolled by pressing the UP and DOWN keys. For example, the event shown in Figure 7 is the turning
on of the amplifier by means of the local switch. For every event/alarm a short description and the date and
time at which it occurred is displayed.
Figure 7: Event stored in the log

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In case of alarm, the value of the measure which caused the alarm is saved into the log. In case of alarm still
existing after five turning-on attempts, the parameter is marked as FAILED. Table 2 is the list of all the events
which can be logged.
Table 2: Events managed and logged by the control board
The log may be completely deleted by selecting Log/Alarms Clear Log/Alarms.
Amplifier can store in the log details about alarms and generic events. You can change this behaviour selecting
Log/Alarms Log/Mode menu item.
- Working Timer
The control board has a working timer which is always enabled while the amplifier is working (i. e. there is at
least one power supply working). The menu entry Working Timer View Timer allows to check the hours
for which the timer has been enabled. Working Timer Timer Reset resets the timer.
- Thresholds
This is a screen showing the alarm threshold of each signals monitored by the control board. The list can be
scrolled by means of the UP and DOWN keys.
EVENT DESCRIPTION
Local ON Amplifier turned on by means of the local switch
Local OFF Amplifier turned off by means of the local switch
Remote ON Amplifier turned on remotely
Remote OFF Amplifier turned off remotely
Interlock open Interlock chain open
Interlock closed Interlock chain closed
Power Supply ON Power supply on
Fwd Pwr xxxxW Alarm for forward power
Ref Pwr xxxxW Alarm for reflected power
UnbY xxxxW Unbalancing alarm
Pwr Sup x: V1 xx.xV Power supply voltage alarm
I1 xx.xA Power supply current alarm
Pwr Sup x: OVERVOLT Power supply overvoltage alarm
Pwr Sup x: OVERTEMP Power supply overtemperature alarm

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- RMS/Peak
The control board can monitor both the RMS and peak powers, the first used in digital systems. The menu
entry Settings RMS/Peak allows to choose the power to be displayed and monitored. This menu is
present only in certain amplifiers.
- Date/Time
This screen allows to set the current date and time. The setting is changed by pressing the arrow keys, then
pressing the RET key to move to the following value and eventually save the changes. To go back to the
previous menu and discard any change made, press the ESC key. Figure 8 shows an example of this screen.
Figure 8: Date and time setting screen
- Display
The menu entry Settings Display allows to change some settings of the display, such has back light,
contrast and screensaver. The back light and the contrast are set by means of the UP and DOWN arrow
keys. The changes made are saved by pressing the RET key or discarded pressing the ESC key. Figure 9
shows an example of this screen.
With Settings Display Screensaver you can set an interval time after which display backlight is
turned off. When display backlight is off, press any key to switch it on.
Figure 9: Display contrast setting screen

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- Frequency (only for some Amplifiers)
The forward and reflected RF powers is measured by means of a directional coupler. In order to compensate
for the effect due to the sampling made by the coupler, it is possible to set the frequency by menu entry
Settings Frequency. The setting can be changed by pressing the arrow keys. The changes made are
saved by pressing the RET key or discarded pressing the ESC key. Set the video carrier frequency.
- Slave Address
The amplifier may be used either in stand-alone mode or as a slave of a master in a high power multiple units
transmitter. In the latter case an unique address for each amplifier has to be specified, in order for all of them
to communicate with the master on the same RS485 bus. The menu entry Settings Slave Address
allows to choose the stand-alone mode or set a slave address by means of the UP and DOWN arrow keys.
The changes made are saved by pressing the RET key or discarded pressing the ESC key. An example of this
screen is shown in Figure 10.
Figure 10:Slave address setting screen
- Remote
The amplifier may be controlled either locally, by means of the keys and display, or remotely. There are three
possibilities for remote control:
- using a direct serial connection between amplifier RS232 connector and a PC RS232;
- using the remote control device manufactured by Elettronika S.r.l. (RCU), on the RS485;
- using a general-purpose control system connected to telemeasures.
You can enable / disable remote control choosing menu item Settings Remote. When remote control
is enabled, the yellow REMOTE LED on the front panel is lit.
- Interlock
One of the pins of the telemeasure connector, located on the rear panel, is used for the interlock alarm. It is an
input line which turns off the amplifier in case of alarm. The interlock check can be enabled or disabled using