Configure AirPort to Jump between 2.4GHz and 5.0GHz

Do not apply a different name to 5ghz.. so AE will show 5ghz using the same name as 2.4ghz but with (5ghz in brackets perhaps) but control of band is up to the client.. it can use either band. That is the default setup .. when it asks for the wireless name in the setup wizard the one name applies to both 2.4ghz and 5ghz. If you changed that.. then reset the AE to defaults and redo the setup.. do not change default.. it will work exactly as you want.

The AE never jumps.. it transmits on both bands simultaneously (at least from gen3 they did.. earlier AE are single band and cannot do what you are asking).

It is the client that swaps bands to the best signal.. Please note BEST SIGNAL does not equal best speed.. on the contrary it will usually connect to 2.4ghz and much poorer speed. That is because there is no way for the client to guess speed. It can only measure signal.

Guest network is identical.. when you setup guest it operates the same way on both bands.. Please also note. Guest network only functions when the AE is the main router of the network.. it will not function if the AE is bridged.

To prove my point I setup from factory default a Gen3 Time Capsule.

Here is what it looks like.

Sorry ran out of edit time.

If you look at the wireless survey you will see the TCwifi and the TCwifiguest are transmitted on both bands.. and the channels are clearly shown.

Nothing is typed or changed in wireless options.. this is default how the AE (or TC same thing with hard disk) works.

1. It works exactly as I showed in the screenshots.. nothing whatsoever has been changed in wireless options.. no name is given.. no box is ticked. If you change the name of the 5ghz then the client cannot swap bands.

2. I use apple's inbuilt wireless diagnostics.. utility.

Been there since Mountain Lion.

About Wireless Diagnostics - Apple Support