You may hear a recording (no airtime charge) that gives procedures for roaming calls and connects you immediately (during business hours) to a registration clerk. If you cannot obtain roaming services on one carrier, try switching to the other type. It is important to remember that the ROAM indicator does not mean the phone is authorized to make calls; only that a system other than the Home system is detected.
SID (System Identification)
In general, metropolitan areas are served by more that one service provider. Under certain circumstances you may be roaming in an area that has two A systems or two B systems that overlap, and you could be charged two roaming charges. To prevent this double charging, program the System Identification Number (SID) for that area and then activate the number when you are in that location. (You will get the SID form the service provider in that location.)
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