Can you use the Airport express as a signal booster without the base unit?

What do you mean, the base unit?

If you are asking about using the AirPort Express to "extend a wireless network" to provide additional wireless coverage....using wireless only.....then you will need another Apple AirPort router configured as your main base station.

Another way of saying the same things is that two Apple AirPort routers are required if you want to "extend" a wireless network using wireless only.

Bob, I wanted to ask you about a comment you made on a similar topic in 2011. Here is link

https://discussions.apple.com/thread/2712750?start=0&tstart=0

If I used old "n" express as extender for my Extreme's 2.5G network would it still impact my 5G network.

Bottom line, willing to accept 2.5 performance to use ipad/iphone outside but do not want to impact Apple TV etc.

Thanks in advance. You seem busy on several topics.

Bob, I meant to say my old b/g express as an extender.

Unfortunately, the older "b/g" Express does not have the settings or capability to "extend a wireless network" if you plan to do this using wireless only.

If you can connect the older Express back to the AirPort Extreme using a permanent wired Ethernet connection, then the Express could be configured to "create" a wireless network using the same wireless network name, same wireless security and same wireless password in Bridge Mode.

The, the older Express would in effect, "extend" the network that way, but devices near the AirPort Express would only receive a 2.4 GHz "b/g" wireless signal.

I used old airport utility 5.6.1 to reconfigure. Plugged old express into extreme with ethernet connection. In wireless mode I "created a wireless network" which had same name and password as the 2.5G network from my extreme. Under internet tab i changed setting to "off (bridge mode)"

Everything looked fine, green light stayed on until i unplugged the express and moved it to the location where I wanted it. Now light blinking amber.

Any thoughts?

Everything looked fine, green light stayed on until i unplugged the express and moved it to the location where I wanted it. Now light blinking amber.

The Express must remain connected via Ethernet cable to function correctly. You will not be able to "extend" without having the Express permanently connected back to the main router using a wired Ethernet connection.

Ethernet cabling can be run up to 100 meters, or about 330 feet without any signifcant loss.

Bob,

I have read a number of your posts regarding FIOS and Time Capsule (or any airport device for that matter). I seem to have found your latest post here and was hoping to ask a question as you seem very knowledgeable about the setup. In one of your prior posts you mentioned that once the Airport device is behind another router (in my case Verizon Actiontec) it needs to be in Bridge mode. Back in 2011 you mentioned that the limitations of Bridge mode is inability of having a Guest network and Wake on network access issues. I was wondering if that is still the case. Also I am not all that worried about the Guest network, but I am having issues with wake on network access (ie I can't file share, screen share from my Macbook Pro to my iMac and also have no ability to wifi sync once iMac goes to sleep).

I have read that it may have to do with the fact that wireless disconnects once the iMac goes to sleep and that is the route of the problem. I have also come accross a post that states that 10.8.3 fixes that issue. The discussion is here https://discussions.apple.com/thread/4160837?start=150&tstart=0

I was very much hoping you can comment on this. Thanks a lot.

I was wondering if that is still the case

Yes, as far as I know.

I have also come accross a post that states that 10.8.3 fixes that issue.

I can't comment on an operating system that has not been released.

Thanks for clearing that up. If i bought a refurbished Express (link below), would I then be able to "extend" my 5G network or is this one limited to 2.5G.

Would "extending" the network slow the whole thing down? What i am trying to do is get a wireless signal in areas of house which are currently dead.

http://store.apple.com/us/product/FB321LL/A/refurbished-airport-express-base-sta tion-with-80211n-and-airtunes#overview

If i bought a refurbished Express (link below), would I then be able to "extend" my 5G network or is this one limited to 2.5G.

Assuming that you already have a simultaneous dual band Apple installed as your "main" router, adding the refurb Express will only extend one band....either 2.4 GHz or 5 GHZ....but not both simultaneously.

If you want to "extend" the 5 GHz network, then you must enable the option to assign a separate name to the 5 GHz network on your "main" router. Then, configure the Express to "extend" that specific network.

5 GHz does not "extend" well, since the signals are much weaker than 2.4 GHz signals, so you will almost need to have line-of-sight between the "main" router and the AirPort Express for strong, reliable 5 GHz performance.

"Extending" using wireless only always results in compromises and a slow down on the network. This will range from 15-50% depending on multiple factors including distance, obstructions and interference from other wireless sources.

It would be much better if you connect the AirPort Express to the "main" router using an Ethernet connection as this will maintain full bandwidth on the entire network....and....you don't need to worry about locating the Express where it can receive a strong wireless signal from the "main" router.