[Q] 850 Mhz Baseband topic

1) Which baseband is needed to support 850 Mhz?
2) What is the command for heimdall to flash a different modem?

What is currently running does not support 3G data in Peru nor the GPS radio.

--- RADIO DATA ---
RIL: I9000XXJVT - b952b2cca19ab65872f9196d42ae64a1
Baseband: I9000XXJVK

--- SOFTWARE INFO ---
Brand: samsung
Model: GT-I9000
Device: GT-I9000, GT-I9000, aries [GT-I9000]
Version: 11-20140820-NIGHTLY-galaxysmtd (f85fdb2bbf)
Release: 4.4.4
Root: true (granted)
Busybox: true (v1.22.1)