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Cisco 3702i TX Power Chart

Cisco 3702i

I recently started a project to completely redo the wifi in one of our buildings on campus. Today, after about a week of hunting as-builts drawings, I was finally ready to start planning my AP deployment. So, I fire up AirMagnet’s Survey Pro and get to prepping the floorplan. As I placed my first Aironet 3702i I realized that I didn’t have a TX Power chart for this particular AP; thanks, Cisco, for the super convenient power selection method.

I did a quick search and came up empty-handed, so I decided to make my own.

Some basic information about Cisco’s TX Power selection:

  • Cisco uses a scale of 1 to 8, with 1 being the highest power and 8 being the lowest
  • Though the scale goes up to 8, not every band uses all 8
  • Each number has a corresponding value in dBm, not mW
  • Each number in the scale can/may represent a different dBm value for different AP models. For example; 8 dBm on the UNII1 band is a 3 for a 2602i, while it is a 4 on a 3502i

The commands I will be using to gather the information to build the charts are:

show advanced 802.11a txpower
show advanced 802.11b txpower

show ap config 802.11a <AP Name>
show ap config 802.11b <AP Name>

These commands do much more than just show power. But for our purposes we will just be needing to gather information on tx power.

The first command, show advanced 802.11a or b txpower, provides power information for every connected AP, as pictured below.

txpower1

 

The second command, show ap config 802.11a or b <AP Name>, provides a wealth of information about an AP in a very easy to read format.

txpower2

Now we have a dBm value to associate with each the power selector setting. All that is left is to create a table for the various bands.

I use AirMangnet’s Survey Pro, which is set-up to use milliwatts (mW) for AP power measuring, so I will be adding a mW column. AirMagnet also only allows for whole numbers so I will be rounding the mW column.

2.4 GHz
TX Power Level dBm mw*
1 23 200
2 20 100
3 17 50
4 14 25
5 11 13
6 8 6
7 5 3
8 2 2
UNII 1
TX Power Level dBm mw*
1 15 32
2 12 16
3 9 8
4 6 4
5 3 2
UNII 2
TX Power Level dBm mw*
1 17 50
2 14 25
3 11 13
4 8 6
5 5 3
6 2 2
UNII 2 Extended
TX Power Level dBm mw*
1 17 50
2 14 25
3 11 13
4 8 6
5 5 3
6 2 2
UNII 3
TX Power Level dBm mw*
1 23 200
2 20 100
3 17 50
4 14 25
5 11 13
6 8 6
7 5 3
8 2 2

Hopefully you found this helpful. If you have any questions or comments please feel free to leave them down below.

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Robert Boardman

4 Comments

  1. Thanks for creating the table! I’ll have to use this as reference because I haven’t updated my charts for 3702.

    I think it’s great you started a blog 🙂

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