← Learning path overview
STEP 04 / 06 · ABOUT 5 MIN

Include the return path

A quarter-wave radiator needs a conducting reference plane.

A simplified groundplane has a radiator and radials. The radials form part of the RF current path, rather than being decorative accessories. At the same frequency and factor, calculated radiator length is approximately one dipole arm.

Radial count and angle affect antenna behaviour. The calculator models only geometric starting lengths. It does not automatically imply good SWR or a particular feed-point impedance. The drawing is a schematic, not installation instructions for a specific product.

Your turn.

Compare the groundplane and dipole drawings at 145 MHz. Identify radiator, radials and feed point. Which calculated lengths match?

Calculate and view a groundplane →
UNDERSTAND & APPLY

Check your understanding

What do the radials do?

Sources & further documentation

Your learning path— / 6
  1. Start with the purpose
  2. Turn frequency into length
  3. Divide the dipole
  4. Include the return path
  5. Separate SWR from loss
  6. Explain your design

After a check, progress is saved only in this browser. No account and no transmission to the server.

View all course progress →