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Antenna Setup?What would be best?Just curious.


h0T_rails
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Just a couple more thoughts- the 25 dBi Yagi will be EXTREMELY directional, so aim gets that much more important than with lesser-gained antennas (this applies to both TX and RX). And with amplifiers, you have to remember that they don't just make your transmitted signal huge, they also usually amplify received noise as well so can actually work against you.

Its worth learning about antenna reciprocity, antenna patterns and polarity, basic RF math (Rule of 3, rule of 10) and things like allowable EIRP as with that 25dBi cannon, you're going already be illegal unless you turn your power down. Now whether anybody really gives a fig is another story, but better to understand what you're doing with both TRUE output power (at the antenna stub) and EFFECTIVE output power (what comes out of antenna, feed cable, and connectors after gain or loss) in case you ever do have to explain yourself.

The better you get in this area, the more you'll appreciate the effect that different antennas have on signal. This is one of the more fascinating parts of working with Wi-Fi for a living. No lecture intended, just trying to help :)

Thank you for the explanation! Nice to have some feedback.

So the yagi is very directional... Maybe not the best option I guess. What would be the appropriate antenna dbi to increase your range without sacrificing on the "direction"?

I'm saying this because, if I check my signal strength, even if I leave my pineapple in one room and move to the next one is very low compared to my home router for instance. Seems that the stock antennas are for close-quarter pentesting.. :)

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The stock antennas are the typical 2.2 dBi "dipoles" or rubber ducks. They have a coverage pattern like figure 4 on this page: http://www.antenna-theory.com/antennas/dipole.php that is the starting poiint to refer other antennas to. And the size of this cell will very on power level out (every 3 dB in power out DOUBLES effective signal strength).

For a crazy strong 25 dBi yagi, you're going to be more like this: http://yagi-uda.com/eleven_elements_yagi-uda.php (don't get hung up the frequencies noted, all Yagis have same general pattern) and all that's happening is the original dipole cell is geing squeezed into the Yagi shape, like with a round water balloon you squeeze to be longer. There's no amplification, just gain in a given direction.

So what's the middle ground? Something more semi-directional (sometimes called patch or panel antennas) like this http://www.newegg.com/Product/Product.aspx?Item=9SIA2970RU5224&nm_mc=KNC-GoogleMKP&cm_mmc=KNC-GoogleMKP-_-pla-_-Wireless+Adapters-_-9SIA2970RU5224

And here's a great paper on antenna theory in general: http://www.cisco.com/en/US/prod/collateral/wireless/ps7183/ps469/prod_white_paper0900aecd806a1a3e.html

and for basic RF math and output effective power, see this excellent write-up http://my.safaribooksonline.com/book/certification/ccna/9780470527658/wlan-rf-fundamentals/rf_math

and one of my own blogs at http://wirednot.wordpress.com/2013/09/05/look-a-bit-beyond-wlan-rf/

(Warning: antennas are addicting).

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Hi,
is it possible to connect MarkV with external long range antenna like the one from Ubiquiti
NanoStation M
This antenna have Ethernet cable to PoE.
and if not, what about hack5 store anntena http://hakshop.myshopify.com/products/14-dbi-panel-antenna?

The nanostation isn't just an antenna, it's also a radio, they work great by the way. The hak5 antenna will need an adapter.

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so, is it possible to connect nanostation with mkV?

Depends on what you want to do with it. It's a long range wireless access point. I've used a few of them to get wired network access to places people didn't want, or could not trench in conduit to run fiber connections. I guess you could use two to bridge an existing network to your pineapple, but that is a weird use case. You can't use it as an antenna for another device.

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