Solved: Newbie question about antenna

brian.oflynn · ‎04-04-2008

Hi, I have been given a 2 x 4402 WLC and 25 x 1242AG LAP to deploy. None of the LAP came with Antenna's. They are to be deployed in an office environment. Would the lack of antenna's prevent me from mounting above the suspended ceiling, or should they go on internal walls instead? I have been unable to do a site survey yet as it is still a building site.

Rob Huffman · ‎04-04-2008

Hi Brian,

You know, I don't think there are any 1242's with Integrated Antennas :(

"The Cisco Aironet 1240AG Series Access Point is an IEEE 802.11a/b/g fixed-configuration, dual-band access point. Built in to the access point are two radios, each with ***dual antenna connectors for diversity."

http://www.cisco.com/en/US/prod/collateral/wireless/ps5678/ps6521/product_data_sheet0900aecd8031c968.html

You would need something like the 1130 Series (with Built-in Antenna).

http://www.cisco.com/en/US/products/hw/wireless/products_category_buyers_guide.html#http://www.cisco.com/en/US/products/hw/wireless/products_category_buyers_guide.html

This does mean that you will require the External Antennas for use with the 1242.

Hope this helps!

Rob

View solution in original post

Rob Huffman · ‎04-04-2008

Hi Brian,

The 1242 AP will require at least 2 External Antennas each but that does not prevent you from mounting the AP itself above the suspended ceiling and then mounting the Antenna's below. As a matter of fact this is one of the recommended designs. Have a look (there are Dual RP-TNC connectors for 2.4GHz b/g radio and 5 GHz a radio) so you will want at least one Antenna for each radio;

Cisco Aironet 1240AG Series 802.11A/B/G Access Point Data Sheet

http://www.cisco.com/en/US/prod/collateral/wireless/ps5678/ps6521/product_data_sheet0900aecd8031c844.html

Cisco Aironet 1240AG Series Access Point Hardware Installation Guide

http://www.cisco.com/en/US/docs/wireless/access_point/1240/installation/guide/124h_c2.html#wp1072615

Antenna Connectors - AP 1242

2.4 GHz

Dual RP-TNC connectors

5 GHz

Dual RP-TNC connectors

Cisco Aironet 2.4 GHz and 5 GHz Antennas and Accessories

The choice you make will depend on the Coverage pattern you desire. There are a number of Models for the 1242 listed here;

http://www.cisco.com/en/US/products/ps6521/products_data_sheet09186a008022b11b.html

Hope this helps!

Rob

brian.oflynn · ‎04-04-2008

Hi Rob, Thanks for the info. I saw it mentioned in one of the documents that there was an integrated antenna in the 1242AG LAP, would this suffice for wall mounting or will an external antenna always be required? Cheers, Brian

Rob Huffman · ‎04-04-2008

Hi Brian,

You know, I don't think there are any 1242's with Integrated Antennas :(

"The Cisco Aironet 1240AG Series Access Point is an IEEE 802.11a/b/g fixed-configuration, dual-band access point. Built in to the access point are two radios, each with ***dual antenna connectors for diversity."

http://www.cisco.com/en/US/prod/collateral/wireless/ps5678/ps6521/product_data_sheet0900aecd8031c968.html

You would need something like the 1130 Series (with Built-in Antenna).

http://www.cisco.com/en/US/products/hw/wireless/products_category_buyers_guide.html#http://www.cisco.com/en/US/products/hw/wireless/products_category_buyers_guide.html

This does mean that you will require the External Antennas for use with the 1242.

Hope this helps!

Rob

ahmedchohan · ‎04-06-2008

Brian

If your AP does not have an integrated antennae and you operate the radio, there is potential for damaging the radio :

"Q. If you operate the radio but do not attach the antenna, can you damage the radio?

A. Some radio equipment manufacturers specifically warn against the operation of radios without the attachment of the antenna. Operation without the antenna can damage the transmitter. Most pieces of amateur or commercial radio equipment carry this warning because the equipment operates at a much higher transmitter power. A failure to use a proper antenna or load causes a reflected wave standing wave ratio (SWR) that can damage the final amplifier stage. This final amplifier stage is the power amplifier (PA).

"

http://www.cisco.com/en/US/products/hw/wireless/ps441/products_qanda_item09186a0080094d01.shtml

For 1242, I'm pretty sure there is no integrated antenna. You can actually know if the 1242 has an integrated antenna by physically looking at and seeing a squaring attachment or a bulge on the AP.