0
$\begingroup$

I need a directional antenna for 10 m that is less than half the size of a yagi or quad with more than about 7 dBi of gain, does anyone know if such a thing exists ?

$\endgroup$
  • 3
    $\begingroup$ sure, does, but what bandwidth do you need? You can usually at most have two of "high gain", "small", "high bandwidth". $\endgroup$ – Marcus Müller Jan 14 at 9:32
  • 1
    $\begingroup$ (e.g. is it OK if you need to use your antenna tuner whenever you change frequency?) $\endgroup$ – Marcus Müller Jan 14 at 12:28
  • 3
    $\begingroup$ half the size in which dimension? (length, width, height, area, volume,...) $\endgroup$ – hotpaw2 Jan 14 at 14:14
  • $\begingroup$ Thanks for the replies, the bandwidth i need is 1 MHz with an SWR of less than 1.6, howver using an antenna tuner is ok. The antenna needs to be vertically polarized. In the case of a yagi it's the length of the boom and the length of the elements that's the problem and also the weight. $\endgroup$ – Andrew Jan 14 at 21:09
1
$\begingroup$

I use a 10m moxon, which when vertically polarized is about 6ft wide. It's probably 80% the height of a similar yagi.

If you use Cebik's model, it should have gain similar to a 3 element yagi, and at least 7dbd gain.

You can control the bandwidth by picking the correct diameter elements. For instance, you could use the outer shield of coax or copper pipe and get some pretty good bandwidth.

Anything smaller will probably need loading coils, and might not have the gain you want.

| improve this answer | |
$\endgroup$
0
$\begingroup$

Look into “Hentenna antenna”. Also there is an approximately half size version with a bit less gain.

Like the Moxon, the Hentenna is composed of two superimposed resonances when perfectly tuned. A sight detuning of either type antenna broadens the bandwidth.

| improve this answer | |
$\endgroup$

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.