NX 100 Transmitter's Technical Summary:

[Ch. Zeshan YousafParticipant]

Transmitter Type:
Medium Wave, AM, 100% Solid State

Configuration:
40 RF power modules, each including a single integrated RF amplifier / modulator.
No frequency dependent parts in Rf module.
Each module is hot pluggable and has internal micro controller for protection and monitoring over a serial bus.
Short circuit protection at the module level offers an added layer of protection.
Dual redundant digital single board exciters utilizing FPGA/DSP technology with automatic changeover.
Pre-correction utilized specifically to improve digital performance.
Redundant low voltage power supplies.

RF Output Power :
Maximum150 kW RMS
Peak Power: 552 kW
Carrier Power Range: 0 to 110 kW
Up to 62 preset levels, presets may include other operational parameters such as DRM vs Analog and different program inputs
Output level stabilized against AC supply voltage variations
Built in Dynamic Carrier Control
Built in AM stereo

RF Output Connection
3 1/8 EIA female standard, other outputs on request
RF Output Impedance
50 ohms, unbalanced
Efficiency
90% typical at 100 kW

RF Load VSWR
16,000 peak reflected watts (1.5:1 VSWR @ 100 kW, 100% modulation) results in instantaneous power shutback
4000 reflected watts RMS (1.5:1 VSWR @ 100 kW, 0% modulation) results in a graceful power reduction

Frequency Range 531 kHz to 1,620 kHz.
“Quick frequency change capability”

Frequency Stability
±2 ppm over temperature range
Optional 300 ppb ovenized source with GPS option

Modulation Type 6 phase direct digital modulation
1.8 MHz modulation sample rate

Modulation Capability
135% positive peak modulation to 100 kW
120% positive peak modulation to 110 kW

Spurious and Harmonic
Meets ITU-R SM.328-10
Meets ITU-R SM.329-9

AC INPUT
Voltage
340 V to 440 V, 3 phase or to customer specifications
Power Supply Variation ±10% voltage, 47 Hz to 63 Hz
Power Consumption 111 kW typical at 100 kW, 0% modulation
167 kW typical at 100 kW, 100% modulation
Power Factor / Cos (theta)
0.95 typical

ENVIRONMENTAL
Temperature Range 0°C to + 50°C
Derate 3°C per 500 m above sea level (2°C per 1,000 ft)

Humidity Range
0% to 95% non-condensing

Altitude 0 m to 4,000 m (0 ft to 13,000 ft)

Cooling Air Requirements
2,550 m3/hr (1,500 CFM)

SAFETY
Meets EN60215: 1976 Safety Requirements for Radio Transmitting Equipment

PHYSICAL
Dimensions
Transmitter Cabinet 184 cm H x 95.7 cm W x 120 cm D (72.4″ H x 37.7″ W x 47.2″ D)
External Transformer Cabinet 116.8 cm H x 113 cm W x61 cm D (46″ H x 44.5″ W x 24″ D)

Weight
Main transmitter cabinet with modules installed: 567 kg (1250 lbs)
Power transformer: 753 kg (1659 lbs)

A U D I O PERFORMANCE
Analog Broadcast Inputs
Dual AES-EBU Digital Audio inputs* adjustable from -30dBFS to 0dBFS for 100% modulation

600 ohms balanced analog audio input +10 dBm nominal for 100% modulation, adjustable from -10 to +12 dBm

Digital Broadcasting Inputs
I,Q over AES-EBU, SRC available* with sample rate converter
I,Q over LVDS, 3 pairs, Clock, Data, frame sync
*Two AES-EBU inputs provided and may be used for either analog audio or digital I,Q inputs
Optional Embedded DRM Generator/Content Server
Optional Embedded HD Radio Generator (Exgine™)

Frequency Response
+0.2 dB/-0.8 dB, 30 Hz to 10,000 Hz.
Optional audio input filters available to meet regional bandwidth restrictions

Total Harmonic Distortion
Better than 0.8% (THD), 30 Hz to 10,000 Hz at 95% modulation (typical)

Intermodulation Distortion
SMPTE 1:1 Ratio, 60Hz/7kHz, 95% Mod Peak – 0.5% @ 100kW (typical)
DIM-B, 2.96kHz/9kHz, 80% Mod Peak – 0.5% @ 100kW

Carrier Shift
0.5% or less
Hum and Noise -65 dB or better below 100kW, 100% modulation

C O N T R O L A N D MONITORING

Extensive Control/Monitoring/Troubleshooting system through 17″ front panel LCD touchscreen. Touch panel control system is non-critical and may be removed from the system without affect- ing transmitter operation or remote control/ monitor via direct wired connections. Redundant back-up control interface provides control in case of front panel computer system failure. Built in instrumentation providing detailed spectrum/im- pedance and modulation analysis.

Metering
Cube
DC Voltages (B+, PA and 15V)
DC Current
Sample Levels (PDM and RF Drive)
Fan Speeds
Heat Sink Temperature

Rack
DC Voltage levels (15V, 5V, 30V, 48V and B+)
Rectifier Fan Speeds
DC Current
Rectifier Heat Sink Temperature
AC Voltage

Exciter
Output Current (RMS, Peak, Carrier)
Output Voltage (RMS, Peak, Carrier)
Forward Power (RMS, Peak, Carrier)
Reflected Power (RMS, Peak, Carrier)
Audio/Modulation Levels (RMS and Peak – Positive/Negative)
Load Impedance

Controller
PDM and RF Drive Levels Ambient Temp

RF Monitor
RF monitor is a power sample (using a directional coupler) that will allow for accurate audio performance measurements

Status
Easy access to current transmitter operating state, past and present alarm conditions and historical trends of both digital and analog channels

Schedule Intuitive easy to read built in scheduler
Up to 144 yearly rules can be defined by user

Remote Control/ Monitoring
Three Remote interfaces:
• Direct wired optically isolated inputs and open collector outputs
• Web interface – All locally available control is available over TCP/IP web interface • SNMPv1

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