30-88MHz FM in 25kHz steps, 118-137MHz AM in 25kHz steps, 138-144 & 148-150.8MHz FM in 25kHz steps, 225-400MHz AM in 25kHz steps. They may have HF UHF SATCOM capability, and it's always possible that in some of the spectrum, they're using encryption or anti-jam (look up ECCM & SINCGARS).