Cisco Aironet 1200 Series

Field Notice: FN - 62164 - AIR-RM22A 802.11a Radio in an AP1200 - 5GHz Antenna Connectors are Reversed

August 2, 2005

Products Affected

Product Affected


AIR-RM22A - 802.11a radio

AIR-RM22A 802.11a radio in an AP1200

Problem Description

If you set the GUI and CLI to the right antenna, all the power comes out the antenna marked left, and vice versa.

This creates installation problems on the connectorized RM22A when an external antenna is used with the product.


Using firmware 12.2(04)JA, the antenna connectors are configured backwards in software.

Typically the right antenna, marked primary, is the active antenna by default. Unfortunately, using this version of code, the left antenna is the default primary, as the antenna control within GUI and CLI is backwards. When the unit is configured to use the right antenna, it will actually set the left one active, and vice versa.


Problem Symptoms

When using the AIR-RM22A 802.11a radio in an AP1200, the transmitted / received signal level observed may differ significantly from what is expected. Configuring the right antenna to be used, it is found that in fact the energy is being transmitted/ received via the left antenna, and vice versa.


The workaround is to simply set the other antenna active in software. After the unit is upgraded to 12.3(07)JA or higher, it will go back to the correct way, so if the user has configured it backwards in software, it will need to reconfigured back to the correct orientation.


To follow the bug ID link below and see detailed bug information, you must be a registered user and you must be logged in.



CSCsb27021 (registered customers only)

Externally found severe defect: Verified (V) AIR-RM22A software refers to antennas backwards

For More Information

If you require further assistance, or if you have any further questions regarding this field notice, please contact the Cisco Systems Technical Assistance Center (TAC) by one of the following methods:

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