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CHA EMCOMM II Performance, NVIS, and DX Planning

CHA EMCOMM II Performance, NVIS, and DX Planning starts with geometry and frequency. The same broadband wire can produce very different regional and longer-path behavior when its height or shape changes.

Product Installation Guides CHA EMCOMM II Reviewed 2026-07-14
In plain language: CHA EMCOMM II Performance, NVIS, and DX Planning starts with geometry and frequency. The same broadband wire can produce very different regional and longer-path behavior when its height or shape changes.

A broadband antenna does not have one universal radiation pattern. The useful pattern is produced by the exact wire shape, height, orientation, ground, and band.

The CHA EMCOMM II V2 is a one-pound, one-operator broadband wire system built for rapid field communication when the station cannot carry a collection of resonant antennas. Its matching transformer and 60 ft insulated radiator pack onto the supplied line winder and can normally be deployed in less than 15 minutes.

What matters for this decision

  • Use the guide’s horizontal geometry with the wire around 10–12 ft high.
  • High-angle radiation can support regional paths only when the operating frequency is below the current critical frequency.
  • A good analyzer match does not prove that the ionosphere will support NVIS.
  • Record band, time, geometry, orientation, height, and on-air reports so the result can be repeated.

Why operators choose this system

Its value is not one universal pattern. The same 60 ft radiator can be kept low and horizontal for regional NVIS work, raised as a sloping wire for general field coverage, or bent into an inverted-L when the site offers two useful supports.

Published operating reference

  • Published continuous frequency range: 1.8–54 MHz.
  • Published power: 200 W SSB and 100 W other modes under intermittent commercial/amateur service.
  • Published wire length: 60 ft maximum and approximately 35 ft minimum deployed length.
  • Published weight and setup: approximately 1 lb; one operator in less than 15 minutes.

Make the next deployment repeatable

Record product revision, configuration, wire dimensions and bearings, endpoint heights, support hardware, return path, coax and choke condition, tuner state, analyzer reference plane, weather, and on-air reports.

Boundary: Broadband coverage does not mean no tuner, identical radiation on every band, or permission to reuse the EMCOMM III counterpoise table. Follow the EMCOMM II V2 configuration and return-path instructions.
Keep the current guide with the station.

This lesson explains the operating choice in plain language. The current guide still controls assembly, dimensions, power limits, and safety.

Open the EMCOMM II V2 User Guide 240317 · View the current product page

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