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AP1242AG's Radio Coverage

I want to know how far is the AP1242AG's able to comunicate with wireless client?

Is it possible to extend about 1km coverage AP1242AG(AP mode not bridge mode) with high dBi antenna?

I think that the AP1242AGs is not like as BR1300 or BR1400, so AP have covrage limitation with high gain antenna,though. is my thought right?


Re: AP1242AG's Radio Coverage

Hi there!

This access point is optimal for indoor environments. You can place it in the outdoor with additional antennas.

This following link lists the antennas that can be installed with Cisco 1242AP.

And please see this product data sheet:

Note that this Access Point can be ordered with two modes either IOS AP or lightweight.

And you need to order the required antennas Separately.

Please rate if it does. And let me know if you have additional questions or the attached documents did not solve your issue.


Abd Alqader


Re: AP1242AG's Radio Coverage

Be advised that on certain channels the A-Radio output power is drastically reduced (down to 25% of max in some cases) in consideration of high-gain antennas (see below).

From: Young Gil Kim []

Sent: Thursday, May 04, 2006 4:57 PM

To: Johnson, Bruce T

Subject: 603479117 Discrepancies in A-Radio power on same and different model radios

Hi Bruce,

This is Young Kim from the Cisco TAC regarding case 603479117. There are a few issues for the power discrepancies.

With the RM21A radio:

The RM21A radio antenna is basically two antennas built into one module:

5 dBi omnidirectional and 9 dBi patch antennas (AIR-RM-21A-x-K9)

When in omnidirectional mode you will have all available power settings, but in patch mode you will run into the same restrictions as the RM-22A radio modules.

The available power settings that you can use on the RM-22A and RM-21A in 9 dBi patch mode depends on which radio channel you are using.

For example:

Channel Freq Highest Power

149 5745 17

153 5765 17

157 5785 14

161 5805 11 <= power gets lower the higher in

frequency (closer to the band edge)

In order for the 802.11A radios to pass FCC emissions with the highest gain antenna that we offer

The device must pass ALL EMISSION TESTING WITH THE HIGHEST GAIN WE OFFER - when tested using the HIGHEST POWER SETTING available to our customers.

Therefore, the RM-21 radio (when in LOW gain antenna mode) and since it's antenna is built in will produce a full 17 dBm across the entire UNII-3 spectrum.

Since in this mode a user can not connect a higher gain antenna, it is permitted to run at full power however, when a connectorized model with external RP-TNC antenna ports are used, the power needs to be scaled back on channels 157 and 161 as

these channels are closer to the band edges.

channel 34 - 48 and 161 highest power level is 11

channel 157 highest output is 14

channel 52 - 60, 149 - 153 is 17

There is a documentation bug that has been opened for this lack of information. The bug ID is CSCeg70287:

show controller dot11 output undocumented

Here is also a useful URL that shows 802.11A transmit power based on band usage:

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