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S/he is wrong, the radio being used is commercially available and runs on the ISM 900Mhz band. Other posts above have all the information about the radios (Ubiquiti M900) and how it works. There is nothing special about this device, with good antennas though, you likely could get 25 or so mile range.

https://en.wikipedia.org/wiki/...
http://www.wlanparts.com/ubiqu...

they simply would have to do a bit of flying in those areas with a SIGINT plane and map out all the transceivers

This may not be as simple as you think. If I were a cartel, I would use directional antennas wherever possible and try to minimize propagation in unwanted directions (like upward where a helicopter might receive it). Something like this, perhaps: http://www.wlanparts.com/product/MT263004NH/900MHZ-SECTOR-ANTENNA-H-POL-125DBI-120-DEG.html Take a look at the vertical beamwidth; that is going to be a pretty weak signal from the air, unless you are lucky enough to find a side lobe of some kind (and even then, your helicopter would have to be moving pretty slowly). Now, I do not know what sort of frequencies the cartels were using or what their specific needs were (maybe they needed something with less of an LOS requirement than 900MHz), so I could be wrong about using directional antennas. It may also be the case that the repeaters do not continuously transmit and that the cartels keep their communications to an absolute minimum, and so hunting for the repeaters from the air may be a difficult thing to do.

Actually, the old WWII huff-duff method would be cheapest and a lot more clandestine way of finding the transceivers. They could easily recruit ordinary citizens (like the British did) to sit at home and report directional and signal strength data from various locations to triangulate the locations of said transceivers. Given that most of these transceivers would be fixed rather than mobile, it would not take long to find and eliminate them.

they simply would have to do a bit of flying in those areas with a SIGINT plane and map out all the transceivers

This may not be as simple as you think. If I were a cartel, I would use directional antennas wherever possible and try to minimize propagation in unwanted directions (like upward where a helicopter might receive it). Something like this, perhaps:

http://www.wlanparts.com/product/MT263004NH/900MHZ-SECTOR-ANTENNA-H-POL-125DBI-120-DEG.html

Take a look at the vertical beamwidth; that is going to be a pretty weak signal from the air, unless you are lucky enough to find a side lobe of some kind (and even then, your helicopter would have to be moving pretty slowly). Now, I do not know what sort of frequencies the cartels were using or what their specific needs were (maybe they needed something with less of an LOS requirement than 900MHz), so I could be wrong about using directional antennas. It may also be the case that the repeaters do not continuously transmit and that the cartels keep their communications to an absolute minimum, and so hunting for the repeaters from the air may be a difficult thing to do.

Get an alfa networks 500mw usb dongle... something like this:
http://www.wlanparts.com/product/AWUS036H/ALFA-NETWORK-WLAN-USB-80211g-up-to-500mW-AWUS036H.html?meta=GBASE&metacpg=AWUS036H&utm_source=gbase&utm_medium=CPC&utm_content=&utm_campaign=AWUS036H

What you need:

(2) wifi bridges (I reccomend senao cb3's) in adhoc mode
(2) Pacific Wireles 24 dbi parabolic antenna w/ N Female ends.
(2) N-Male to RP-TNC Pigtails preferably LMR 400 (length dependant on application).
(2) Roof Mounts (style dependant on application).

Put it all together and you've got at least 5mbps of real throughput between homes, and it will be under $500.

All of the above is available here.

Do you have neighbour's in your line of site with broadband? If so, buy a pair of high gain directional antennas, and set up an 802.11 link.

You can buy such antennas here: http://www.wlanparts.com/

I do! hell, the wifi setup on my laptop puts out 604mW. I have a 200mW Z-COM, Prism2.5, PCMCIA Card connected to a 5.5dBi Antenna(1), 4.8dBi gain after connecter and cable loss are calculated in. If you were to connect this card to a converted PrimeStar dish with a biquad feeder(2) (27 - 31dBi gain) you would have an EIRP of 159 watts... In other words, don't point it at your gonads!

(1) http://www.wlanparts.com/c=So0zbsGg2Glh7swrUjbpMQG KP/product/RV24-5RD
(2) http://www.trevormarshall.com/biquad.htm

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