c350 activate 850mhz and 1900mhz

[3gtech]

Hey friends, i've a c350 900/1800 from Germany, i'll try to activate the 850/1900 band, I had to read a lots of post in this forum, and try whit the v180 0025_0001 seem, and modifiy (check) 3,1,0 and activates the 1900 band, that works but not ok. lost the signal, if I want to make a call, give me a error... so....
what you recomend?????
:cool:

[3gtech]

and I'll also try in a v66i (activate the 850mhz band)
please help!

[sky178]

practically it is not working, because a filters and tx & rx circuts is defferent