Regular Operation as per DS			GSM SPEC

GSM900 Tx: 870.4 ... 921.4 MHz			880.0 ... 914.8	
GSM900 Rx: 864.4 ... 966.2 MHz			925.0 ... 959.8

GSM1800 Tx: 1702.4 ... 1919.8 MHz		1710.2 ... 1784.8
GSM1800 Rx: 1804.8 ... 1996.4 MHz		1805.2 ... 1879.8

GSM850 Tx:  

[824.2 ~ 837.0 MHz]
[837.2 ~ 848.8 MHz]


GSM810 Tx: 					806.0 ... 821.0
* modify B value to go down to 125 (A = 60)
GSM810 Rx:					851.0 ... 866.0
* modify B value to go down to 132 (A = 62)