Monday, 24 April 2017

A portable multi-band End-Fed Half Wave (EFHW) antenna for 40-10m

The camping washing line spool used for the antenna wire.
A few people have asked about the 30m antenna Norfolk Amateur Radio Club used for its International Marconi Day (IMD) operations at Caister Lifeboat this year.

Ten Megahertz (30m) turned out to be a useful band for us, allowing CW contact after CW contact, despite poor conditions after a geomagnetic storm and a K index of five.

The antenna we used was a portable 40-10m multi-band end-fed half wave (EFHW) with a 49:1 Unun using an FT240-43 toroid.

It used a wire 9m vertically metres up a fishing pole and then about 5.8m out.

The novel thing was that I only built it the day before and it uses a Coghlan camping washing line spool with the string taken off and about 21m of wire wound onto it.


  1. What kind of choke should be used? A few loops of coax, some ferrite beads, something else? Thanks.

  2. See G3TXQ's site at It depends on the frequency you are operating on. Too for for >4 KOhms would require 10 turns of RG58 on a 4.25 inch former or 12 turns on an FT240-61 Toroid at 14MHz.

  3. Nice blog, thanks for sharing such a nice blog.

  4. Steve loved talk to HARS.Sometimes you recommend 200-2 toroids and sometimes 243-43, what is difference please M0OLG

    1. T200-2 toroids (red) are made of iron power and good for making tuned circuits, such as used in the monoband EFHW. FT240-43 toroids are made of ferrite and are better suited to wideband transformers, such as the multiband EFW. Hope that helps.