V3 Razr: Which band is being used?

I've got a V3 Razr -- I'm wondering if there is any way to tell whether
the phone is using the 850MHz or 1900MHz band?

The reason I ask, my parents have 1900MHz only phones, we're finding
that I have reception in places where they don't have any signal at all.

I'd like to tell whether it's just that their phones have worse RF
performance in general, or whether buying 850MHz-capable phones would
solve it.

Thanks in advance!

--
They say you shouldn't say anything about the dead unless it's good.

"He's dead. Good."