Download PRESENTATION OF 20 kW Band II FM TRANSMITTER Air Cooled

TB02-202F 20 kW Band II FM TRANSMITTER
Dual Drive Configuration
PRESENTATION
OF
20 kW Band II FM TRANSMITTER
Air Cooled Type
Compact Design – Very High Efficiency
TB02-202F 20 kW Band II FM TRANSMITTER
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TB02-203F 20 kW FM BAND II TRANSMITTER
The TB02TB02-203F belongs to the
High Power VHF product family
of FM Radio Transmitters fully
solid state technology air cooled.
The 20 kW family operating in
the Band II or Band I (OIRT) for
FM stereo sound broadcasting.
The equipment is fully compliant
with the personnel safety
requirements as specified in EC
215.
The transmitters have been
designed to offer to the
customer high performances,
high reliability and great
simplicity in their operation and
maintenance procedures.
Key Features
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Transmitter
Model
Band
Frequency
MHz
Output Power
Standard Comply
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TB01-203F
I (OIRT)
65.80 to 74.00
20kW
OIRT
TB02-203F
II
87.50 to 108.00
20kW
CCIR and FCC
Dual Drive Configuration
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BROADBAND frequency synthesizer, without any other
tuning or alignment.
MONOPHONIC & STEREOPHONIC emission
according to the CCIR rec. 450450-2 standard.
RDS & SCA subcarriers input capability
HiHi-FiFi-quality modulated signal, with low residual
noise and distortion.
Digital Exciter with DDS process upup-gradable
AESAES-EBU digital interface available as option
RF Signal free from spurious and harmonic
signals
MOSFET to obtain wide band , reliability , and
high efficiency.
Redundant 5 x 4kW RF power amplifier and
power supply
Hot pluggable any RF power amplifier
Dual Drive ; 1+1 ; N+1 Redundancy
configuration capability
High Tolerance mains voltage (±
(± 20 %) is
accepted by the transmitter
Mains Protection System by means of Surge
Arrester System (option)
Remote Operation compliant to IEC 864864-1 rule
(all option are available)
Control System including fault finding
PROTECTION AND CONTROL SYSTEMS
Block against emission on spurious frequencies
Reflected power
Modulation limiter
Air cooling system fully integrated and outdoor
conveyable
Very low acoustic noise -64 dBA
High efficiency ≥ 60 % with cooling system
included
Compact design only one 600 mm rack 42 unit
height is used
TB02-202F 20 kW Band II FM TRANSMITTER
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Dual Drive Configuration
Modularity
The Transmitters employ a modular system for
the main sub-assembling: this provides the high
standardisation of the spare part, so that the
same units can be installed, as spare part, for
several transmitters throughout the Medium
power range from 5 kW to 40 kW.
25 W High
Performance
Stereo FM Exciter
High level of performance
These transmitters were specifically designed to comply with
the latest international standards and the requirements of
advanced broadcasters, meeting tighter specifications than
usually required, at an affordable cost.
Great care went into producing a Hi-Fi-quality modulated
signal, with low residual noise and distortion.
The RF signal is also free from spurious and harmonic
components to a higher degree than required by CCIR and
most national standards.
TB02-202F 20 kW Band II FM TRANSMITTER
WideWide-Band Amplification
The RF amplifier is made up by five RF
modules (2A(2A-402S) installed in the rack
, the modules are dedicated for the
Sound FM carrier amplification.
The nominal output power for each
module is 4000 W ; the amplifiers
employ solid state MOSFET technology
in order to obtain wide band , reliability
and high efficiency .
Each RF module has an own redundant
switchswitch-mode power supply unit selfselfprotected against overover-current and
overover-voltage , as well the overovertemperature , overdrive and VSWR for
RF parameters.
The power supply units are installed
below the RF modules in the separate
hot pluggable draws. The redundant
system provides to feed 50% (worst
case) of the each RF module final
stage.
RF IN
Dual Drive Configuration
RF OUT
A /ϕ
DRIVER STAGE
OUTPUT STAGE
2A 402S FM Amplifier
Simplified block diagram
TB02-202F 20 kW Band II FM TRANSMITTER
Key Features
Broadband, without any other
tuning or alignment.
High Output Power up to 4kW
continuous
MOSFET technology
Redundant Design due to twelve
paralleled devices to the final stage
Power Supply Replacement
facility allowed by separate plug-in
Air Cooling System with high
efficiency , tanks to new design of
the
heat-sink layout
Amplitude and Phase
Adjustment facility accessible from
panel
Diagnostic completely available in
locally and remote
Very Low MTTR (Mean Time
Trough Replacement) only 10
minutes in the worst case.
Easy Maintenance all internal
subunit can be replaced without
soldering and complicated procedure
for alignment.
Compact Design allows to
minimize the dimensions and weight
Dual Drive Configuration
2A 402S FM 4 kW Amplifier
Internal layout
TB02-202F 20 kW Band II FM TRANSMITTER
Dual Drive Configuration
CLEAN DESIGN
Rear rack view with open door
Each RF module has an own
redundant switch-mode power supply
unit self-protected against overcurrent and over-voltage , as well the
over-temperature.
The power supply units are installed
below the RF modules in the separate
hot pluggable draws. The redundant
system provides to feed 50% (worst
case) of the each RF module final
stage.
TB02-202F 20 kW Band II FM TRANSMITTER
Dual Drive Configuration
Mains Protection System
The Mains Distribution Unit is
installed in the lower side rack , it
provide to feed the subunits with
unregulated AC prime power
supply , the protection against the
accidental line sparks is performed
by means of surge arrester system.
The high tolerance mains voltage
(± 20 %) is accepted by the
transmitter , so that in the most
situations, the Automatic Voltage
Regulator is not necessary.
TB02-202F 20 kW Band II FM TRANSMITTER
Dual Drive Configuration
Easy Operation and Maintenance
The Control Unit provides the full
management of the transmitter without
the operator presence, the system
involves a central controller and several
peripheral units installed in each RF
module and rack.
The control system includes a fault
finding for detecting equipment
malfunctions and locating the faulty
subassembly which need to be replaced;
the basic controls as Start - Stop Standby - Reset and power readout are
permanently available.
The interlock circuit is independent of
the of the control system and remains
always operational during the presence
or not of the control unit.
TB02-202F 20 kW Band II FM TRANSMITTER
Dual Drive Configuration
Equipment Redundancy
The equipment design allows the soft degradation (RF power loss)
for several transistors faulty; the table below shows it.
0
Output
power
reduction
-0,5
-1
dB
-1,5
-2
-2,5
-3
-3,5
-4
0
5
10
15
20
Number of the transistors failed
(total final stage transistors = 60 )
RELIABILITY ASPECTS
Soft degradation about devices