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Cisco access point questions (seperating antennas and antenna extenders)


On the Cisco 1242 access points, I have two questions:
1) If we get external antennas; we plan to mount the access point and then mount the antennas a few feet from them (connected to the access point).  The antenna cables are around 1.5 feet long.  My question is can we get extensions?  So we could mount the access point, for instance, in the office, with a 25ft antenna extender to the warehouse?  What's the limit on the length of the antenna extension cable?

2) If we want to, for instance, cover two areas with the access point - can we run one antenna to the one area (with an extension), and another antenna to the other area?  The 1242s have 4 antennas - to my understanding 2 are used for 2.4ghz, and 2 are used for 5 ghz.  Can we run one 2.4 and one 5 to the one area, and the other 2.4 and other 5 to the other area, to have coverage in both?
Someone told me once that they use one antenna to transmit and one to receive, and for that reason it's not a good idea to seperate the antennas.  Is that true?  Just trying to get a better understanding on this

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You can extend the antenna cable using a flylead, as Davorin said.  I wouldn't say 24ft is a long length though.  I've done thousands of internal and external installations with coax runs in excess of 50m.  You should use a calculator to determine the various dynamics (cable length, antenna gain, transmit power, etc.).  It's quite acceptable to use a really long cable length to bring your EIRP within legal limits, for example.

Again, as Davorin said, separating the antennas on each band is not acceptable.  That is true in any installation.  They should only be used to provide coverage for one cell.  You can use the 2.4GHz radio to cover one area, and the 5GHz radio to cover another area but you cannot split them, so putting one antenna on 2.4GHz in one area and the other 2.4GHz antenna in a separate area will not work.

You should be able to use the 5GHz frequencies without applying for a licence if it's for indoor use.  Bands A and B should be ok, but Band C is usually for fixed-wireless outdoor applications and should not be used indoors.