*#06# displays IMEI on 8700, NOT on 6200, 7500, 8200
To activate RBS:
(pause means the * key held in until box appears)
[pause] [pause] [pause] 1 1 3 [pause] 1 [pause] [ok]
You now have to press the [MENU] and scroll to the 'Eng Field Options' function with the < or > keys, and enable it. (thanks Red Ripper)
To de-activate RBS,
[pause] [pause] [pause] 1 1 3 [pause] 0 [pause] [ok]
This only works with some versions of software. Please report what works and doesn't for you.
Reported working, by country:
Uses of RBS:
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