Connectivity issues

Unanswered Question


I have a 1231 AP (AIR-AP1231G-A-K9) with an external antenna (AIR-ANT2506). It used to work just fine with the AIR-ANT4941 2.4GHz antenna but we needed to extend the coverage, when we attached the AIR-ANT2506 antenna there is intermitent connectivity no matter if users are close to or far from to the AP. There is no objects which are blocking the signal nor other RFI. Is the antenna the right one for the AP? Any clue about why this is happening?

thank you in advance for your help

I have this problem too.
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rob.huffman Fri, 01/22/2010 - 09:01

Hi there,

You probably want to set and connect to the Right Primary and take the setting out of Diversity which would have
been set if you were using 2 x 4941's.

Use the antenna configuration interface command to configure the radio receive or transmit antenna settings. Use the no form of this command to reset the receive antenna to defaults.

[no] antenna {receive | transmit} {diversity | left | right}

Syntax Description


Specifies the antenna that the access uses to receive radio signals


Specifies the antenna that the access uses to transmit radio signals


Specifies the antenna with the best signal


Specifies the left antenna


Specifies the right antenna


The default antenna configuration is diversity

This example shows how to specify the right receive antenna option:

AP(config-if)# antenna receive right

Hope this helps!


hi rib,

I actually did that, I configured the transmit and receive antenna to be the right one but it didn't work. I also performed a carrier busy test, here are the results

Frequency  Carrier Busy %
---------  --------------
   2412          4
   2417          2
   2422          2
   2427          6
   2432          4
   2437          2
   2442          4
   2447          2
   2452         22
   2457         21
   2462         33

Frequency  Carrier Busy %
---------  --------------
   2412          9
   2417          0
   2422          9
   2427          0
   2432          0
   2437          8
   2442          3
   2447          1
   2452         29
   2457         18
   2462         33

Frequency  Carrier Busy %
---------  --------------
   2412          2
   2417          2
   2422          0
   2427          0
   2432          0
   2437          0
   2442          1
   2447          1
   2452         31
   2457         25
   2462         38

the AP is configuredd in channel 6 which is not that busy.

What else should I check?

Thank you in advance.

George Stefanick Fri, 01/22/2010 - 23:22

Here are a few ideas..

1) Put the old antenna back on for testing purposes and see if your issue goes away

2) Is the new antenna defective?

3) Test coverage are static locations (10 feet, 20 feet, 30 feet) with both the new and old antenna to check performance

4) I see you did a busy test, but did you check the spectrum with a spectrum card ?

thank you Geroge for your reply,

1) with the old antenna the AP was working just fine, but the coverage is limited with no problems, I mean in 30 ft round there is no problem

2) we don't really know if the antenna es defective but ever since we put the antenna to incrase the coverage in the farther places the connectivity goes up and down

3) with both antennas there is no problem within the first 30 ft beyond that we have signal only with the new antenna but the connectivity is not constant

4) I didn't, don't have the spectrum card

Is there something else I can do?



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