OVERVIEW

COM-TECH designs and manufactures a comprehensive range of Channel Combiners for Broadcast TV and Radio Stations.
COM-TECH Combiners are available with different cavity sizes, for low to high power applications, and with different number of poles, to match all masks and standards requirements (DVB, ATSC, ISDB, DAB).

COM-TECH develops combiners with different Combination Techniques: Manifold, Starpoint, and Balanced.
COM-TECH has exploited the Multi-Channel Combination, improving the overall Multi-Channel Performances and extending the capability to combine Adjacent Channels.

COM-TECH Combiners are easily and Fully Tunable all over their operating band, are Temperature Stabilized, and have a built in DC Short. They feature a convenient Interchangeable Connector System, and most of them are completely modular thanks to a Modular Frame System.
COM-TECH Combiners make use of innovative and proprietary design techniques, such as: XLine, DualCross, SIR, Interdigital Hairpin, EVA-ModeMultiStep.

Low power Combiners can conveniently be integrated into 19” Rack Shelves. Medium and high power Combiners can be provided with Heat Sinks, Forced Air Cooling and Liquid Cooling to efficiently increase their input power.
The COMBINERS family is coded and categorized firstly with reference to the operating frequency band (UHF Combiners, VHF B.III Combiners…), subsequently by Combination technique (Manifold, Starpoint or Balanced), and finally by Combiner Series (CL Series, FC Series…)

UHF Combiners

VHF B.III Combiners

VHF B.I-II Combiners

DAB Combiners

FM Combiners

Frequency Range 470-862 MHz 174-240 MHz 47-100 MHz 174-240 MHz 87.5-108 MHz
Standards DVB-T / T2
ATSC
ISDB-T
DVB-T / T2
ATSC
ISDB-T
DVB-T / T2
ATSC
DAB / DAB+ / T-DMB
Combination Techniques Manifold
Starpoint
Balanced
Manifold
Starpoint
Balanced
Starpoint Starpoint
Balanced
Manifold
Balanced
Order 5, 6, 7, 8-Pole
4-Pole (Analog / No Mask)
5, 6, 8-Pole
3, 4-Pole (Analog / No Mask)
6-Pole 6, 7, 8-Pole 2, 3-Pole
Techniques XLine
DualCross
XLine
DualCross
SIR
Interdigital Hairpin Design
EVA-Mode
DualCross
SIR
EVA-Mode
Cavity Size 20 mm to 220 mm 30 mm to 200 mm 60 mm to 110 mm 60 mm to 200 mm 80 mm to 220 mm
RMS Input Power 80 W to 37.5 kW 150 W to 45 kW 325 W to 1.3 kW 250 W to 7 kW 425 W to 2.5 kW
RMS Output Power Up to 70 kW Up to 65 kW Up to 2.6 kW Up to 40 kW Up to 7 kW

FEATURES

Full Band Tunability
COM-TECH Filters and Combiners are designed to be easily and completely tunable:

  • Fully tunable all over their operating band
  • Tunable in accordance to all worldwide standards, channel widths and regulation masks
  • Customizable Tunings in accordance with Customer specifications
  • Designed to be easily tuned (Tuning Instructions available on request)
  • Engineered to be tuned with a standardized set of tools (Tuning Toolbox available on request)

Temperature Stabilization
COM-TECH Filters and Combiners feature a state-of-the-art Temperature Stabilization, achieved through:

  • Innovative interactive CAE design (3D EM and Fluid Dynamic simulation)
  • Accurate choice of materials
  • Environmental and laboratory tests

DC Short
COM-TECH Filters and Combiners have a built-in lightning protection:

  • Solid DC Short Circuit towards ground on the input/output couplings
  • No Open Circuits, in order to avoid dangerous charge accumulations
  • Full protection towards the antenna side

Interchangeable Connector System
COM-TECH products feature an interchangeable and modular connector system, based on unified mounting panels.
Each panel accept different connectors, allowing a wide choice of connections to be mounted on the same product:

  • Panel sizes: 25 mm, 32 mm, 64 mm, 100 mm, 130 mm, and 150 mm
  • Wide choice of connectors available on each product
  • Easy connector change

Modular Frame System
COM-TECH Modular Frame System, available on medium and high power Combiners (SM, SF, DM, DF Series), allows a complete Combiner modularity:

  • Easy and convenient possibility of extension, integration, module switch, and maintenance
  • Modules separable to be easily shipped, and later assembled and installed on site
  • Integrable with Directional Couplers (with Monitor Panel), Patch Panels, System Monitor

XLine: Extracted-Pole Elliptical Response
COM-TECH innovative and proprietary Extracted-Pole design technique, available on 6 and 7-pole low-power Filters (CL Series) and Combiners (SB, DB Series):

  • Two Transmission Zeros
  • Compact, in-line form factor
  • Balanced Combiners: Adjacent Channel Combination

DualCross: Double Cross Coupling
COM-TECH innovative and proprietary Double Cross-Coupling design technique, available on 6 and 8-pole medium and high power Filters (FC, TF, TS, TC, BF Series) and Combiners (SM, SF, DM, DF Series):

  • Four Transmission Zeros
  • Enhanced Selectivity
  • Optimum Insertion Loss and Efficiency
  • Balanced Combiners: Adjacent Channel Combination

SIR; Interdigital Hairpin; EVA-Mode
COM-TECH innovative and proprietary designs, leading to very compact yet full-band VHF and FM Filters:

  • SIR: Novel resonator design, for compact VHF B.III Filters (TS Series)
  • Interdigital Hairpin: Unique resonator design, for ultra-compact low-power VHF B.I-II Filters (HR Series)
  • EVA-Mode: Highest Quality Factor in the smallest space, available on VHF B.I-II and FM Filters and Combiners (HE, CE, ME Series)

MultiStep: Ultra-Flat Frequency Response
COM-TECH exclusive and proprietary design technique, available on high power UHF Hybrid Couplers, (NH Series) and Balanced Combiners (DF Series):

  • Ultra-Flat frequency response (10 times flatter compared to traditional design Hybrid Couplers)
  • Enhanced Return Loss and Isolation
  • Antenna Systems: Accurate power balance
  • Balanced Combiners: Agile connection of several modules with unparalleled performances

Coding
Combiners product codes are named with reference to Series, Order, Technique, Size, and Number of Channels:

Series MX, DM…: Manifold, Compact Modular…
Order 4, 6, 8…: No. of Probes
Technique E: Cross Coupling     X: XLine     D: DualCross     P: All-Pole     N: 2-Notch
Size 60, 80…: Cavity Size in mm
Band C: UHF     B: VHF B.III     A: VHF B.I-II     R: DAB     F: FM
No. of Channels 2, 3, 4…: No. of Filtered Channels

OPTIONS

19″ Rack Shelves
COM-TECH products have been engineered to be easily and conveniently fit into 19’’ Rack Shelves. COM-TECH can provide standard and customized solutions to integrate Filters, Combiners, Directional Couplers, Lowpass Filters, and other components and accessories into 19’’ Rack Shelves:

  • Specifically designed for COM-TECH Filters and Combiners
  • Compatible with standard 19’’ Racks
  • Customizable front panel

Notes

  • Components inserted in 19’’ Rack Shelves, with limited or no ventilation, might suffer from an increased over-temperature; power ratings should be consequently reduced
  • In any applicable case, the body temperature must be kept below the maximum value (65°C, 149°F)

Heat Sinks
Heat Sinks expressly designed to efficiently reduce the over-temperature on Filters and Combiners, and to consequently increase their maximum operating power:

  • Specifically designed for COM-TECH Filters and Combiners
  • Add-on option, can be conveniently added subsequently

Notes

  • Power ratings with the Heat Sinks Option are calculated with fins in vertical position and with no obstructions to the natural air flow
  • Power ratings can be further increased with the aid of extra ventilation (E.g. through the internal transmitter ventilation)
  • In any applicable case, the body temperature must be kept below the maximum value (65°C, 149°F)

Forced Air Cooling
The innovative Forced Air Cooling system allows to dramatically reduce the over-temperature on Filters and Combiners, and to consequently increase their maximum operating power. Thanks to the downsizing possibility, the Forced Air Cooling allows significant cost and space savings:

  • Complete and standalone system, not requiring any external parts
  • Variable speed fans controlled by microprocessor, allowing fans to operate at the minimum flow
  • Premium quality DC 24 V brushless fans, engineered to be quickly and easily replaced
  • Multi-standard (110-230V, 50-60 Hz) switching power supply
  • Contact Alarm for over-temperature, missing power or any kind of electrical failure
  • Add-on option, can be conveniently added subsequently 

Notes

  • In any applicable case, the body temperature must be kept below the maximum value (65°C, 149°F)

Liquid Cooling
The innovative Liquid Cooling system allows to dramatically reduce the over-temperature on Filters and Combiners, and to consequently increase their maximum operating power. Thanks to the downsizing possibility, the Liquid Cooling allows significant cost and space savings:

  • Conveniently integrates with the transmitter liquid cooling system
  • Compatible with most NTP connecting threads
  • Chemically compatible with available coolant liquids
  • Thermo-sensor included (70°C – 158°F N.C. SPST)
  • Add-on option, can be conveniently added subsequently

Notes

  • In any applicable case, the body temperature must be kept below the maximum value (65°C, 149°F)