Low-Power FM Transmitters (LPFM):
AXON

Some common questions:

Low Frequency FM transmitters, Low Wattage FM transmitters or Low Watt FM transmitters: are they the same as a Low Power FM Transmitters?
Yes, people often use these terms interchangeably to call this type of equipment.

What is the difference between Low Power FM Broadcast Transmitters, Low Power Radio Transmitters, Low Power Radio Station Equipment and the one called Low Power FM Transmitter?
The difference is that Broadcast equipment is designed for a very professional application in Radio Broadast.
The characteristics of this type of equipment are of superior quality and reliability compared to Low Power FM Transmitters used for Cars, for example.
Low Power FM Transmitters aim at converting a line audio input to FM (to then play this audio line back on the radio).

In our broadcast market, all our equipment is designed for broadcast applications, even if – to make things easier – many people call our Low Power Broadcast FM Transmitters just Low Power FM Transmitters.

AXON HIGHLIGHTS

AXON Is produced in a wide Range of Output Power:

• 30W (30 watts)
• 50W (50 watts)
• 60W (60 watts)
• 100W (100 watts)
• 150W (150 watts)
• 300W (300 watts)
• 500W (500 watts)
• 600W (600 watts)
• 1000W (1000 watts, 1kW)
• 1200W (1200 watts, 1,2kW)

Analogue Frequency Modulation from 87.5 MHz to 108.0 MHz.
Japanese (JPN), Russian (OIRT 66 - 47 MHz) and more bands are also available.

An Exclusive Distortionless Intelligent Soft Limiter keeps the maximum deviation in the 75kHz limit, giving always the maximum possible volume preventing any kind of distortion.

An AIR FILTER provides high protection to the internal components.

An LCD front panel display, a Direct Access Keys command and LEDs indicators allow immediate control and visualization of the overall status of the transmitter.

An N+1 Profiles connector provides 7 different memory selections.
Memory settings are located in the internal memory and can be selected both remotely and locally.

A High efficiency LDMOS technology of up to 80% of efficiency, with total spectral purity.

AXON can be used as a Low, Medium or High Power FM Transmitter, in a stand alone station, as well as a driver with complex high power FM Radio Transmitters and N+1 systems.

AXON: TECHNICAL CHARACTERISTICS

• Frequency Range: 87.5 ÷ 108.00 MHz
• Ranges of Output Power: 30W (30 watts), 50W (50 watts), 60W (60 watts), 100W (100 watts), 150W (150 watts), 300W (300 watts), 500W (500 watts), 600W (600 watts), 1000W (1000 watts, 1kW) and 1200W (1200 watts, 1,2kW)
• Modulation Modes: Mono, Stereo, Multiplex, SCA, RDS, Aux
• Input Levels: -3 to +6 dBm
• Pre-emphasis: Flat(0)/50/75 µs selectable from front panel
• FM S/N Ratio: -89 dB
• AM S/N Ratio: -60 dB
• Total Harmonic Distortion + Noise: 0.03% @ 400 Hz
• Transient Intermodulation Distortion: 0.03%, 2.96KHz square wave and 14 KHz sine wave
• Monaural: Audio Frequency Response: ±0.15 dB, 30 Hz to 15 KHz. Input Connector: XLR female
• Multiplex: Composite Amplitude Response: : ≤ ± 0.1dB, from 30Hz to 53kHz. Input Connector: BNC female
• Stereo: Audio Frequency Response: ±015 dB from 30 Hz to 15 KHz. Input Connector: XLR female
• AES /EBU: Amplitude response: ≤ ± 0.1dB, from 30Hz to 15kHz. Sampling Frequency: from 32 to 96 KHz with automatic selection, D/A Converter: 24 bit.
• AC Input Power: 230/400 VAC ±15%, 50/60 HZ(+/- 3HZ) single phase
• Operating temperature: -10°C to +50°C.
• Max Operating Altitude: 4000 mt.
• Protection against Lightning, Dust and Corrosion
• Size: 88mm. (H) x 484mm. (W) x 478mm. (D) 2 unit cabinet
• Weight: ~ 11 Kg.
• Options: WEB TCP/IP-SNMP Remote Control, AES/EBU Input, Dynamic RDS coder, OIRT and JAPAN Bands
• 24 V DC power supply input option (24 V and 48 V DC for AXON 30 and AXON 50, 48 VDC for AXON 100, AXON 150 and AXON 300)
• Fully μP controlled

HIGHLIGHTS

• Professional analogue compact FM transmitter with: MPX (composite), stereo, digital AES/EBU and mono audio base band inputs;
• Analogue Frequency Modulation from 87.5 MHz to 108.0 MHz. Available in JPN JAPAN and OIRT frequencies;
• Excellent audio fidelity with soft, deep and clean crystal sound. Very low signal to noise, very low distortion and high stereo separation thanks to digital stereo coder;
• Dynamic RDS encoder with TMC function;
• Wide range of power available from 30w to 1200w;
• Air filter and PCB boards fully tropicalized giving high protection to the internal components;
• Aluminium air ducts: an exclusive design of the air flow, guide the air into aluminium ducts avoiding contact of the air coming from the fans with the electronic components. This avoid failures produced by the air corrosion;
• Totally made in aluminium: for minimum weight and maximum robustness;
• Easy maintenance: all parts, RF modules, electronic control boards, blowers, power supplies are easy to replace;
• Uninterrupted service thanks to intelligent software protections;
• Free failure design thanks to hardware fast protections;
• Solid State LDMOS technology up to 80% High Efficiency constant at any power level;
• Total spectral purity: better than -90 dBc spurious and harmonics for highest RF signal quality;
• Friendly User Interface with Direct Keys for main commands and LEDs indicators to show the overall status; smart browsing with ENTER and ESC Keys;
• All the LINE of FM Transmitters share the same spare parts;
• Parallel remote control connectors;
• Seven selectable profile connectors for use in N+1 system;
• Full-range power supply: 90-260 vac mains voltage;
• Compliant with all the standards: ETSI – CCIR – FCC;
• External 10mhz and 1pps synchronization for use on SFN (Isofrequency) applications;
• Remote control by WEB TCP/IP and SNMP of all signal parameters controlled by internet without the help of any external box or accessories;
• Over-dimensioned components that determine the reli­ability; heat sink, fans, dummy loads, LDMOS, power supply;
• Copper Carrier on  active power components such as LDMOS or unbalanced power resistors;
• Hot plug-in power supply;
• Standard market available power supply;
• SMP: superior modular philosophy: Modularity with very light amplifier modules (less than 17kg/34lbs each);
• Lowest loss of power on the market in case of failure of one module;
• Top seller in Governmental, Private Networks, Commercial and Community radio stations;
• Mirror networking mirror system available to keep track of the function of all parameters over time. It records millions of parameters collected every year;
• Touch screen WEB Based Brain Control Unit.

COMPACT ARCHITECTURE FM TRANSMITTERS

Compact architecture means: the complete FM transmitters are built in a single chassis and cover all the functions: FM Exciter or Modulator and FM Amplifier.

The Compact configuration is well suited for low power up to 1 kilowatt or maximum 2 kilowatts.

Power limit to use compact configuration

Transmitters in compact configuration over 2KW become less reliable and difficult to maintain.
The weight of a compact transmitter is extremely important because, if too high, two people are needed to handle it, thus increasing the cost of maintenance on site.

Last but not least, in case of fault the transmitter remains off-air, creating big troubles for the broadcasters. In the case of power higher than 2kW, of course, modular configuration is a more reliable choice.

Brief description of the principle of functioning of an FM Exciter-Modulator

The FM Exciter takes in the Base Band or Audio Input to create the RF Signal, with the frequency modulation to be transmitted.

The Base Band Inputs are: Mono, Left & Right, Composed MPX or Digital AES/EBU.

The base band signal, inside the Modulator, goes through several electronic processes to obtain the 75kHz frequency deviation.

In case of stereo, the Left and Right channels code to get the composed signal MPX to be transmitted.

Depending on the settings Pre-emphasis is applied.

Once the base band composite MPX signal is completely processed, it is carried to the VCO to be modulated, converting this amplitude information in frequency modulation information.

The quality of this process has a direct impact on the final quality of the sound of the radio.

The last link on the equipment chain, responsible of transmitting all the quality of the audio, is the FM Modulator.

Each of these processes require high precision in the treatment of the signal.
For this reason, the broadcaster must choose only Top Quality Professional Broadcast Equipment.

The AXON Series of FM Transmitters definitely fulfills this requirement.

PROFESSIONAL ANALOGUE FM TRANSMITTER WITH MPX COMPOSITE, STEREO, DIGITAL AES/EBU OR MONO AUDIO BASE BAND INPUTS.

AXON is a Professional FM Transmitter/Exciter with Analogue Frequency Modulation from 87.5 MHz to 108.0 MHz in a 10 kHz step and a frequency stability better than 2 ppm.

Audio base band input and modulation mode selectable in: MPX (Composite), Stereo, Digital AES/EBU or Mono.

EXELLENCE AUDIO FIDELITY WITH SOFT, DEEP AND CLEAN CRYSTAL SOUND.
VERY LOW SIGNAL TO NOISE, VERY LOW DISTORTION AND HIGH STEREO SEPARATION.

The Sound Quality of the Music, the most important feature of the AXON Series, features with Warm Softness, Deep and Clean Crystal Sound.

This excellent audio quality highlights the mood of the radio giving a measurable competitive advantage compared with any others brand of transmitters.

Very low S/N typical 85 dB, high stereo performance coder with typical 65 dB Stereo Separation and Ultra Low distortion 0,01%.

An Exclusive Distortionless Intelligent Soft Limiter keeps the maximum deviation in the 75kHz limit, giving always the maximum possible volume preventing any kind of distortion.

AES-EBU digital input 24 bit resolution with: 32, 44.1, 48, 96 KHz sample rates, automatically selected.

AIR FILTER AND PCB BOARDS FULLY TROPICALIZED

All of our products are equipped with an AIR FILTER mounted on the front panel and easy to clean or to replace.

The PCB Boards and the wiring are fully tropicalized by a specific coating for electronic assembly.

An Air Filter and Tropicalization provide high protection to the internal components when the equipment is installed in places with dust, humidity, salt and pollution.

These precautions guarantee a long life in extreme environmental conditions, preventing damage due to corrosion and erosion, protecting the components from the inclemencies of the tropical climate.

Copper Carrier on LDMOS Active components and unbalanced Resistors

Active power components such as LDMOS or unbalanced power resistors are mounted on a copper carrier to improve heat dissipation and greatly facilitate maintenance; in fact, in cases where LDMOS are mounted directly on the heat sink, this causes high heat sink dissipation and it becomes almost impos­sible to heat the weld.

ALLUMINUM AIR-DUCTED 2U CABINET

The equipment is housed in a compact rack mountable 2 Unit Aluminium cabinet.

An exclusive design of the air flow inside the transmitter guides the air into aluminium ducts, avoiding contact with the electronic components.

Every component that produces heat is mounted on a heat sink.

The Air passes exclusively into the aluminium heat sink, avoiding contact with the electronic components.

UNINTERRUPTED SERVICE WITH HARDWARE AND SOFTWARE PROTECTIONS

There are two kinds of protections: Fast Hardware Protection and Soft Software Protection.

In some conditions, like in case of a short-circuit on the antenna or the coaxial cable, the protection must be hardware and act in a few nanoseconds. The software would not indeed be fast enough, in this case, to grant protection of the equipment.

When the fault condition is soft, as in the increase of VSWR caused by snow or humidity, a software protection can be use.

In the AXON series of FM Transmitters are implemented both:Fast Hardware Protections and Soft Software Protections.

The software protection reduces the output power without on-air interruption, keeping the RF devices always within the safe operating parameters.

The transmitter is protected in case of:

• Load mismatching, antenna short/open circuit
• Excessive external temperature
• Cooling failure
• Amplifier breakdown
• Over and Under Voltage DC
• Over and Under Voltage AC
• RF and Power Supply Temperature

Beyond the Hardware or Software protection, the transmitter is designed to be rough, to keep it functioning perfectly even in the worst operating conditions.

To achieve this, the important components of the transmitter are over-dimensioned or hardware-protected:

6th generation LD-MOS High Efficiency and VSWR 65:1.

Over-dimensioned switching power supply with PFC (Power Factor Corrector).

Over-dimensioned Heat Sinks and Fans.

Integrated AC Mains filtering.

Integrated lightning protection.

Integrated overvoltage spikes on the mains protection.

HIGH EFFICIENCY LDMOS TECHNOLOGY UP TO 80% EFFICIENCY, CONSTANT AT ANY POWER LEVEL

AXON use Solid State RF power devices, 6th generation LD-MOS High Efficiency and VSWR 65:1 to deliver high reliability and low energy consumption.

The high Efficiency is kept constant at any power level, thanks to an intelligent algorithm that controls the Voltage Power Amplifier and the Bias to obtain maximum efficiency at any frequency and at any output rated power.

TOTAL SPECTRAL PURITY: > -100 DBC SPURIOUS, > - 84 DBC HARMONICS

The RF module amplifier design and the output filter broad band keeps optimum performances on spectral purity without the need of tuning.

USER-FRIENDLY DIRECT KEYS AND LEDs INDICATOR USER INTERFACE

An LCD front panel display, Direct Access Keys command and LEDs indicators allow immediate control and visualization of the overall status of the transmitter.

A Quick and easy navigation through menus creates a user-friendly, simple and intuitive interface, together with full control and an immediate measurement of all working parameters: Output Power Power, Frequency (from 87.5 to 108 MHz), SCAs, Stereo/Mono/MPX, Dynamic Limiter etc.

TOUCH SCREEN BRAIN CONTROL UNIT

The control unit has the specific function to supervise the transmitter, even in case of failure (or if turned off); manual control of the transmitter guarantees perfect operation.

Weekly scheduler Power Derating

The output power can be programmed depending on the time needed for energy consumption optimization management.

AVAILABLE OPTIONS

• A wide range of options is available, to reduce the need of any additional equipment:
• High performances Stereo Encoder
• Digital AES/EBU
• Dynamic RDS Encoder with TMC Function
• AOIP Audio Over IP
• WEB TCP/IP and SNMP connectivity for remote Access
• Japanese (JPN), Russian (OIRT) and more bands are also available
• Parallel Remote Control Connector Interface

REMOTE CONTROL BY TCP/IP: WEB + SNMP OF ALL SIGNAL PARAMETERS

• Web control
• E-mails configuration available (sent in case of alarms).
• Web log file: Up to 64000 events stored in the web board. The log file is saved in the PC in common text format (.txt)
• SNMP v2c with Traps and Informs
• Weekly scheduler page Available for the modification of the basic parameters of the unit up to 4 times for each day
• Extremely detailed web control with all main parameters fully controllable and adjustable, available without proprietary tools. Weekly scheduler page with up to 4 events for each day for energy consumption optimization management.
• REMOTE DEEP DIAGNOSTIC CAPABILITY: The industrial standard allows to safety handle huge quantity of information to perform remote deep diagnosis.
• Measurements of more than 100 operational parameters including current, voltage and temperatures of each power supply and each RF module.

PARALLEL REMOTE CONTROL CONNECTORS

Parallel Remote Control Connector Interface with dry contact relay outputs and opto-isolated inputs with the following signals available: on/off, local/remote, alarm status, RF higher than a preset threshold, reset of alarms, change between 6 available memories (for 6 different configurations of the unit).

N+1 Profiles connector: provides 7 different memories selection. Memory settings are located in the internal memory and can be selected both remotely and locally.

TOP SELLER IN GOVERNMENTAL, PRIVATE NETWORKS, COMMERCIAL AND COMMUNITY RADIO STATIONS

AXON is one of the most used FM Broadcast Transmitters in the Top Ranked Governmental and Private Networks, Commercial and Community Radio Stations.

For any application AXON is the ultimate solution that meets the most demanding customer requirements and guarantees professional features at an affordable price.

COMPLIANT WITH ALL THE STANDARDs: ETSI – CCIR - FCC

AXON meets all the most rigorous electromagnetic quality standards.

To combine both, our mission is to give maximum reliability as well as maximum performance to our products: to achieve this, we have adopted unique solutions in the broadcast industry.

AXON EXCITER/TRANSMITTER

30W TO 1200W

Frequency Range: 87.5 ÷ 108.00 MHz, Programmable in 10 KHz steps

On request 66 ÷ 74 MHz (OIRT), 76 ÷ 90 MHz (JPN) Bands.

Frequency Stability: better than ±150Hz from -10 to +50°C

Max deviation: +/-150kHz.

Frequency Control: Synthesizer µprocessor control.

Power Output: 30W, 50W, 100W, 150W, 300W, 600W, 1200W. Adjustable from 0W to maximum power.

Output Impedance: 50 ohm.

Display: forward/reflection power and modulation indicator

Type of Modulation: Direct frequency modulation of carrier frequency, F3E Stereo with Subcarrier and Mono .

Lock in Time: Typ. 4 second.

Off Lock Attenuation: ≥ -80 dBc.

Modulation Capability: ±150 KHz.

Modulation Mode: Mono, Stereo, Multiplex, SCA, RDS, Aux.

Pre-emphasis: Flat(0)/50/75 µs selectable from front panel.

Asynchronous AM S/N Ratio: -60 dB below reference carrier with 100% AM modulation @ 400 Hz, without FM modulation.

Synchronous AM S/N Ratio: -60 dB below reference carrier with 100% AM modulation@ 400 Hz with FM modulation ±75 KHz @ 400 Hz.

RF Harmonics: Exceeds ETSI/EBU/CCIR/FCC requirements. better than 84 dbc

RF Spurious: Exceeds ETSI/EBU/CCIR/FCC requirements. better than 84 dbc

Output Connectors: 30W to 600W N type connector, 1200W DIN 7/16 type connector

Output power on/off and adjustable from front panel and remotely.

Overall Efficiency up to 80%.

Monitor RF: -60 dBc, BNC connector

VSWR: 1.5:1 Maximum with automatic fold-back at higher VSWR

MONAURAL OPERATION

Audio Input Impedance: 600 ohm balanced, 15 Kohms unbalanced.

Audio Input Level: -6 to +12 dBm. (Other range on request)

Input Connector: XLR female.

Audio Frequency Response: ±0.15 dB, 30 Hz to 15 KHz.

Total Harmonic Distortion + Noise: 0.03% @ 400 Hz

Intermodulation Distortion: 0.03%, 1 KHz/1.3 KHz, 1:1 ratio

Transient Intermodulation Distortion: 0.03%, 2.96KHz square wave and 14 KHz sine wave.

FM S/N Ratio: -89 dB RMS detector, -85 dB below ±75 KHz deviation, 50 µs de-emphasis, weighted.

MULTIPLEX OPERATION

Composite Input Impedance: 5 Kohm unbalanced.

Composite Input Level: 3.5Vp-p for ±75KHz deviation.

Input Connector: BNC female.

Composite Amplitude Response: : ≤ ± 0.1dB, from 30Hz to 53kHz

Total Harmonic Distortion + Noise: 0.03% @ 400 Hz

Intermodulation Distortion: 0.03%, 1 KHz/1.3 KHz, 1:1 ratio

Transient Intermodulation Distortion: 0.03%, 2.96 KHz square wave and 14 KHz sine wave.

FM S/N Ratio: -89 dB RMS detector, -85 dB below ±75 KHz deviation, 50 µs de-emphasis, weighted.

STEREO OPERATION

Audio Input Impedance: 600 ohm balanced, 15 Kohm unbalanced.

Audio Input Level: -12 to +12 dBm.

Input Connector: XLR female.

Audio Frequency Response: ±015 dB from 30 Hz to 15 KHz.

Total Harmonic Distortion + Noise: 0,03% @ 400 Hz

Intermodulation Distortion: 0,02%, 60Hz /7kHz 4:1 ratio +4dBu

Transient Intermodulation Distortion: 0.03%, 2.96 KHz square wave and 14 KHz sine wave.

FM S/N Ratio: -85 dB RMS detector, -82 dB below ±75 KHz deviation, 50 µs de-emphasis, weighted.

Stereo Separation: 30÷80 Hz ≥ -53 dB, 80Hz÷15 KHz ≥ -65 dB (Typ. 70 dB).

Crosstalk attenuation: Main to Sub -55 dB 30 Hz to 15 KHz

38 KHz Suppression: ≥ -70 dB (typ. -85 dB).

Pilot Frequency: 19 KHz ± 1 Hz

Phase Pilot: ± 2° adjustable

Output Pilot: 1 Vpp., BNC female

Audio Filter Attenuation: ≥ -55 dB @ 19 KHz, > -45 dB 20 KHz to 100 KHz.

Modes: Stereo, Mono L+R, Mono L, Mono R.

AES/EBU OPERATION

Input Level: -10dBfs to 0dBfs

Input Connector: XLR female, optical TOS-LINK.

Input Impedance: 110 ohm.

Data Format: S/PDF,AES/EBU, IEC958, EIAJCP340/1201.

D/A Converter: 24 bit.

Sampling Frequency: from 32 to 96 KHz with automatic selection

Stereo separation (crosstalk): ≥50dB,100Hz to 5kHz

Amplitude response: ≤ ± 0.1dB, from 30Hz to 15kHz

FM S/N Ratio: -85 dB below ±75 KHz deviation, 50 µs de-emphasis, weighted.

SCA, RDS, AUX OPERATION

Input Connector: BNC female

Input Impedance: 3 Kohm.

Input Level: -3 to +6 dBm.

Frequency Response: ±0.2 dB, 40 KHz to100 KHz.

Input Connector: BNC female. Most SCA, RDS, AUX, performance parameters are determined primarily by the generator used.

AUXILIARY CONNECTIONS

USB: connector Type B female front panel.

N°2 RS485: Serial Interface connector RJ45 back panel.

Telemetry Interface: connector DB25F back panel.

External Clock: connector SMA female (optional).

OPTIONS

External clock: for PLL synchronization purpose 1-2-2.5-5-10 MHz external r eference oscillator with self selection of the incoming frequency.

DOUBLE EXCITER WITH AUTOMATIC CHANGEOVER SYSTEM

SNMP TELEMETRY INTERFACE

GSM AND PSTN TELEMETRY

TCP/IP TELEMETRY INTERFACE

SINCH-MODULE FOR SFN APPLICATION

OIRT & JPN VERSION

DIGITAL AUDIO INPUTS

LPFM CODE STATION:FCC IDENTIFICATION CODE

RDS CODER : EASY PROGRAMMABLE BY PC

SCA Encoder

Digital Composite 192kHz Input