Cell Info/Area Info Display and Roaming Indicator?

To get signal levels and tower info, dial:

3001#12345#

(The forum software erases the asterisks that have to "surround" this string, so it's asterisk-3001#12345#-asterisk)

To get an indicator when you are roaming on an AT&T partner network, call 611 and ask them to activate the (free) "Off Network Alpha Tag" on your account. If they ask why, tell them you want to be a good guy and observe the (usually unenforced) data limits while roaming.

-dan

Message was edited by: DanH to add asterisks

There is alot of data in the Field Test Mode; the most useful is the RX level, which tells you what the tower signal strength is (-50 is full signal, -110 is no signal); and the ARFCN number, which tells you the broadcast frequency (1 to 124 means you're on 850-900 MHz frequency). Also, if you look at the screen for a while, you'll see that the tower at the top sometimes switched to another tower, because you've moved and another tower has a stronger signal. There is some information of the Tower Id. but you'd have to work for AT&T to decode this in to something meaningful.

As for roaming, when you're in the US, the iPhone automatically roams/searches for the best tower signal strength; and when you're overseas, you can switch the iPhone to automatically roam for suitable carriers (Settings>Carrier>Automatic), or you can select one of the options manually; however, there is no symbol to show you that you are roaming.

Hope this answers your questions.

Message was edited by: jia10

The field test screen is useful for finding out about signal strength and whether there are multiple towers within range. I don't know what you mean by "name."

The Off Network Alpha Tag is indeed the icon you need in order to show that you are roaming. It appears at the top of every screen when you are using the phone and either says "AT&T" or "Off Network." It does not show the name of the roaming partner. So if it says AT&T you are not roaming and if it says Off Network you are. Very simple and a lot easier to spot than a tiny triangle IMHO.

If Alpha Tag is not activated on your account, your phone will always say AT&T.

-dan

-dan

Does the alpha tag show when I am roaming domestically as well? My phone roams on Centennial most of the time so a lot of times I don't use it, and its a pain to check the field test screen all the time. (Which by the way, network 410 is AT&T, 255 is T-Mobile, and 30 is Centennial)

On a second note, has anyone had any problems with roaming on Centennial too much? Most of the time I don't even get to use my iPhone because I'm worried about getting my service terminated, so I wind up using my Sprint BlackBerry.

-Charlie

To piggyback onto these questions, is there any way to "open" roaming on the device, so one might link up to a roaming partner of AT&T that has better coverage in a specific area? For example, if you are on the edge of an AT&T tower and are struggling with signal, but T-mobile has available network in that area, can you manually switch over to the T-mobile network using any of these tools?

Charlie:

The alpha tag shows roaming ONLY when it is domestic. I asked for it to be activated for the same reasons as you.

However, bear in mind that the AT&T contract language says you cannot exceed 6 MB off-network in any TWO CONSECUTIVE months, so some creative juggling of your use can allow you to, for example, use a lot of data in June, then less than 6 MB in July, and tons of data again in August and not risk ET.

I also told CS when I requested the alpha tag to flag my account to show that I frequently spend time in northern NY (partner networks) but continue to live and use my iPhone primarily on Cape Cod (regular AT&T). Not sure if this will help, but I read online that it can and figure it can't hurt.

-dan