Two ways to put a wire in the air and ask it to talk to the world
You do not need an antenna engineering degree for this. Both antennas use a long wire and let you connect the radio near one end. The big difference is how each antenna uses the coax cable connected to it. The simple choice is this: an EFHW is usually the easier “planned bands” antenna; an End Fed OCF is usually the more flexible “many bands” antenna, but it asks you to pay closer attention to the cable route and choke.
Three main parts
Wire
Coax cable
Choke
The part that does most of the talking to the air.
The round cable that carries radio energy between your radio and the antenna.
A part that helps stop the outside of the coax cable from accidentally joining the antenna party.
A picture is worth at least several meters of wire
These drawings are simplified on purpose. Real antennas also react to their height, nearby trees or metal, the ground, and the cable route.
Meet the EFHW
EFHW means End Fed Half Wave. “Half wave” is radio shorthand for a wire length chosen to work well on a particular band. Imagine a jump rope being wiggled in a very neat rhythm. An EFHW is happiest when its wire length and the radio band line up in a useful rhythm.
Good news
Small print
Simple idea: a single wire with the radio connection at one end.
Often a good fit when you know the main bands you want to use.
Popular for portable operation because it can be quick to put up.
The connection end can have high RF voltage. Treat it with respect, insulation, and safe distance.
It can work on more than one band, but the best bands are usually related to the original half-wave band.
A choke helps keep the coax from becoming an uninvited extra antenna.
Meet the End Fed OCF
End Fed OCF means End Fed Off Center Fed. In the version described here, it is not simply a regular two-wire dipole. It uses the long wire as one side and a chosen section of the outside of the coax as the other side. That may sound sneaky, but it is deliberate: the choke tells the coax where this “antenna side job” should end.
Good news
Small print
Can be a good option when you want one wire system to cover more HF bands.
The feedpoint often has a more moderate electrical “fit” than an EFHW end.
A shorter wire can sometimes cover many higher HF bands, depending on the design.
The coax route matters because part of its outside is intentionally radiating.
The choke position matters. Moving it or the cable can change the antenna.
A tuner may still be useful on some bands. No antenna receives a lifetime exemption from physics.
Quick compare
Question
EFHW
End Fed OCF
Best starting personality
Simple and focused
Flexible and more hands-on
What is the coax doing?
Mostly carrying the signal
Part of the antenna for a defined section
Best for
A planned set of compatible bands
Broader multiband experimenting
Main watch-out
High RF voltage at the feed end
Coax route and choke location affect results
Will I ever need a tuner?
Possibly, especially away from its friendly bands
Possibly, depending on the selected bands and installation
How to choose without getting lost in the weeds
If you want to get on the air with a straightforward wire and have a few target bands in mind, start by looking at an EFHW.
If you want more bands from one end-fed setup and do not mind treating the coax route as part of the antenna design, start by looking at an End Fed OCF.
If the antenna changes when you move the cable, mast, or choke: congratulations, you have discovered that those pieces are part of the antenna system. That is normal; measure and adjust one thing at a time.
A low SWR reading is good, but it is not the only score. Also watch for radio-frequency interference, heat in the matching parts, received noise, and whether contacts are actually improving.
On higher frequencies, an EFHW can become less efficient than an End Fed OCF unless you use a monoband EFHW. Consider the specific design and intended bands rather than assuming either style wins everywhere.
