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CHA BV Engineering and Matching Guide

CHA BV Engineering and Matching Guide works best as a controlled adjustment, beginning with the current guide setting and changing one variable at a time.

Product Installation Guides CHA BV Reviewed 2026-07-14
In plain language: CHA BV Engineering and Matching Guide works best as a controlled adjustment, beginning with the current guide setting and changing one variable at a time.

A useful field setting is a starting point, not a magic number. The surrounding ground, mount, nearby metal, and deployed return wires all move the installed resonance.

The CHA BV is for operators who want a straightforward resonant vertical without giving up the ability to change the system later. The standard kit brings together the CHA BLANK feed point, SS17 whip, M-COIL, PUCK HUB, four 12.5 ft radials, spike, tent stakes, and 12 ft choked RG-58 coax.

What matters in this configuration

  • Start from the guide table, sweep below and above the band, and move only the variable that corresponds to the observed resonance. Shorten the whip when resonance is low; lengthen it when resonance is high. If the dip is in-band but shallow, adjust radial count or length one step at a time.
  • A tuner or low station-end SWR does not prove that the antenna is resonant, efficient, or using the intended return path.
  • Save the final setting for the exact band and site, then verify it again whenever geometry or hardware changes.

Why this choice matters

CHA BV is a resonant, single-band-at-a-time MPAS READY vertical that covers 40 through 6 meters in its documented SS17 configuration and can grow into other guide-defined builds. The useful result comes from the complete documented system rather than any one threaded component.

The parts that make it a complete antenna

  • CHA BLANK feed-point adapter
  • CHA SS17 telescoping whip
  • CHA M-COIL for 30 and 40 meters
  • CHA PUCK HUB and four 12.5 ft banana-plug radials
  • CHA SPIKE, four tent stakes, and line winders
  • 12 ft RG-58 coax with an integrated RFI choke

Use the result in the field

Record the exact radiator, loading or feed-point hardware, return system, mount, feed line, band, dimensions, and final measurement. Repeatability is more valuable than a one-time low SWR reading.

Before you transmit

  • Confirm whether the build uses SS17 with M-COIL or SS25 with M25-COIL.
  • Use the guide table for the selected band, whip length, radial count, and radial length.
  • Keep the supplied feed-point choke in the coax path.
  • Inspect the mount, threads, whip, radials, and clearances before transmitting.
  • Sweep broadly at low power and change one variable at a time.
Boundary: SS17/M-COIL and SS25/M25-COIL are different electrical configurations. Similar appearance or the same thread does not make the coils interchangeable.
Use the current source before deployment.

This lesson explains the decision in plain language. The current product guide controls assembly, settings, ratings, and safety.

Open the CHA BV User Guide · View the current product page

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