Is it possible to use 2 airport expresses1 airport extreme(5th generation)?

Question

1 is 802.11n and 1 is 802.11g
the airport extreme is 802.11n
I use the N model as an extender for the extreme atm but I was wondering if I could use both as extenders for the 1 extreme? please help if you know how to do this! Thanks in advance!

Answer 1

Static WDS Setup with "Mixed" (802.11g & 802.11n) AirPort Base Stations
Note: To facilitate the WDS set up:
Perform a "factory default" reset on all of the base stations that you plan on using in the WDS. This will get them back to their respective "out-of-the-box" configurations.
To avoid having to "switch" wireless networks within the AirPort Utility, temporarily connect the remote (& relay) base station(s) to the AEBSn or Time Capsule by Ethernet during the set up phase, and then, relocate it to the desired location when complete.
Be sure to jot down the AirPort IDs (MAC addresses) for each of the base stations to be used in the WDS. The AirPort ID is printed on the label on the bottom/side of the base station.
Main Base Station Setup
Click the AirPort status menu in the menu bar and choose the wireless network created by the base station you want to set up as the main base station.
Open AirPort Utility (located in the Utilities folder in the Applications folder on a Macintosh computer, or in Start > All Programs > AirPort on a computer using Windows).
Select the main base station, and then, choose Manual Setup from the Base Station menu.
Enter the base station password if necessary. If the base station is using the default password of public, you will not be prompted for a password.
Click Wireless in the toolbar, and then, choose “Participate in a WDS network” from the Wireless Mode pop-up menu. Note: You will need to hold down the Option key in order to get this option on the AEBSn, 802.11n AirPort Express Base Station (AXn), or Time Capsule (TC).
Click WDS and then, choose “WDS main” from the WDS Mode pop-up menu.
Select the “Allow wireless clients” checkbox if you want client computer to connect to this base station.
Click the Add "+" button and enter the AirPort ID of the base station you want to connect to this base station.
Click Update to send the new settings to the base stations in the WDS.
Remote Base Station Setup
Open AirPort Utility; select the remote base station, and then, choose Manual Setup from the Base Station menu.
Enter the base station password, if necessary.
Enter the same network password as the main base station, if necessary.
Click AirPort in the toolbar, and then, click Wireless. Choose “Participate in a WDS network” from the Wireless Mode pop-up menu, and then, choose the same channel as the main base station from the Channel pop-up menu.
Click WDS and choose “WDS remote” from the pop-up menu.
Enter the AirPort ID of the main base station in the WDS Main field.
Click Update to transfer the settings to the base station.
Relay Base Station Setup
Open AirPort Utility; select the relay base station, and then, choose Manual Setup from the Base Station menu.
Enter the same network password as the main base station, if necessary.
Click AirPort in the toolbar, and then, click Wireless. Choose “Participate in a WDS network” from the Wireless Mode pop-up menu, and then, choose the same channel as the main base station from the Channel pop-up menu.
Click WDS and choose “WDS relay” from the WDS Mode pop-up menu.
Enter the AirPort ID of the main base station in the Main AirPort ID field.
Click the Add "+" button and enter the AirPort ID of the remote base station this relay base station will connect to.
Click Update to transfer the new WDS settings to the relay and remote base stations.
(ref: Pages 42-46 of "Designing AirPort Networks.)
(ref: Wi-Fi base stations: Extending the range of your wireless network by adding additional Wi-Fi base stations)