DVB-T Modulator TERRA mdx420 (2xAV/COFDM encoder & RF modulator)

Code: R82518
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Twin Channel Amplifier: Terra at420 (UHF, analog TV & DVB-T, AGC)
Twin Channel Amplifier: Terra at420 (UHF, analog TV & DVB-T, AGC)
Twin Channel Amplifier: Terra at420 (UHF, analog TV & DVB-T, AGC)
View of the device
Twin Channel Amplifier: Terra at420 (UHF, analog TV & DVB-T, AGC)
Distinguishing features
  • Generation of DVB-T mux modulated by input analog audio/video signals (COFDM modulation scheme)
  • Two audio/video channels (two independent sets of A/V inputs for connecting two A/V sources)
  • Output frequency range: 110-860 MHz,
  • Maximum output level: 85 dBμV,
  • Output level adjustment range: 0...-15.5 dB (0.5 dB step)
  • C/N ≥ 50 dB
  • Audio level adjustment: -6...+6 dB by 2 dB step (reference level: 775 mV)
  • Control via buttons and joystick located on the front panel
  • OLED graphical display
  • DIN-rail mountable, also in 19" RACK cabinets
The mdx420 DVB-T modulator is a professional device designed for combining additional audio/video signals into shared antenna systems. The signals may come from cameras, multimedia players, computers, DVD players, satellite receivers etc. The device has two audio/video channels (two independent sets of A/V inputs for connecting two A/V sources). The output DVB-T RF channel (multiplex carrying the both A/V signals) can be distributed in any MATV/SMATV system in a multi-dwelling unit, hotel, hospital, shopping mall etc.
The device generates DVB-T RF channel in compliance with EN 300 744 standard, with maximum output level of 85 dBμV. It has been designed and manufactured in pursuance of 2002/96/EC directive. The output RF channel can be selected within 110-860 MHz range.
The mdx420 can be used and mounted individually, e.g. on a wall (using the accessories supplied with the device), or together with other components of antenna systems (on DIN Rail Rack Mounting Bracket R82538). The application of the DIN rail and a RACK cabinet is an ideal solution in the case of headends with separate satellite receivers.
The device needs a 12 VDC, 0.65 A power supply. One module can be powered from any stabilized 12 VDC power supply with the minimum current capacity of 0.65 A. When the module is used together with other components of Terra headend, all the modules should be powered with the dedicated power supply DR-60-12 R82532.
The complete Terra solution for MATV (shared antenna) systems includes a range of components that can be selected according to the current needs and requirements of customers:
  • R82510 - at420 - twin channel amplifier
  • R82511 - at440 - four-channel amplifier
  • R82515 - mt420 - twin VSB multi-standard modulator
  • R82520 - ma400 - multiband amplifier ((FM/VHF/UHF inputs) with high maximum output level
  • R82532 - DR-60-12 - DIN rail power supply capable of powering up to 8 system devices
  • R82536 - 699.20 - DC distribution cable for 4 modules
  • R82538 - universal DIN rail mounting bracket matching 19-inch RACK cabinets for up to 8 system devices and power supply
  • R82540 - 699.026 - F-F coaxial bridge for signal links between adjacent modules
An example set of the amplifiers and modulators for a MATV system. For maximum system stability,
the number of modules on each side of the power supply should not exceed 4 units.
Name mdx420
Code R82518
Output frequency range [MHz] 110-860
Range of TV channels                                            6-12, 21-69, S1-S38
TV standard                                           EN 300 744
RF output
Maximum output level [dBμV] 85
Impedance [Ω] 75
Output level adjustment range [dB] 0 ÷ -15.5 (step 0.5)
Frequency range of RF loop [MHz] 47-2150
Max DC pass through current [A] 0.3
RF loop insertion loss[dB]             2-3 dB
Return loss [dB]                                         ≥ 10
C/N ratio [dB] > 50
Video inputs
Input level [Vpp] 1 ±0.1
Impedance [Ω] 75
Bandwidth 20 Hz - 6 MHz
Audio inputs
Bandwidth  [Hz] 20...15000
Input level [mV] 775
Impedance [kΩ]  10
Audio level adjustment [dB]                           -6...+6 (step 2)
Video processing
Encoding ISO/IEC13818-2  MPEG-2 MP@ML

720 x 576 (at 25 fps)

720 x 480 (at 30 fps)

Frame rate
max 25 (PAL, SECAM), max 30 (NTSC)
Bit rate of compressed stream [Mbps] 2...9
Audio processing
Encoding ISO /IEC11172-3 (MPEG1 audio) layer 2 compliant
Sampling frequency [kHz] 44.1
Bit rate of compressed stream [Kbps] 256
Mode Stereo
RF modulation
MER [dB] ≥ 35
Modulation schemes
Channel width [MHz] 7/8
Guard Interval 1/4, 1/8, 1/16, 1/32
FEC 1/2, 2/3, 3/4, 5/6, 7/8
Mode (number of carriers) 2k
Physical specs
Supplying voltage [V] 12
Current consumption [A] 0.65
Operating temperature range [ºC] 0...50
RF connectors
Audio/video connectors
Dimensions [mm] 198x107.5x48.5
Weight [kg] 1.12