Question about 850/1900hz cell phone bands.

Hi guys. My name is Jane. Looks like you have a pretty well rounded forum here. Pretty cool actually! Got a question for anyone with a communications background. I've got some spare antennas lying around and looking at buying a cheap booster. Found an 850hz for a good price. My question is is the 1900 pcs band necessary? Is it just a back up for the providers? Futhermore, if i have dual band antennas say a yagi outside and a tiny omni inside would I see any amplification on the 1900hz without a repeater? Forgive my ignorance I think I slept through a good many of my rf courses.

The answer depends on your country, carrier and location.

Most signal boosters are deployed at a fixed location. For some carriers it is possible to look up the local cell tower for your location (there may be more than one) and find out what frequency it operates on. Many towers operate on multiple frequencies.

It is possible but unlikely that putting a yagi on the roof and an omni inside will result in any improvement. The gain associated with the yagi will be eaten by coax loss and free space loss between the omni and the antenna in your cell phone. You could also create additional dead spots where the signal from the omni destructively interferes with the original transmitted signal (similar to multipath problems). Cell RF carriers are wide enough this is not usually an issue but your mileage may vary.

If you have internet service, you would probably be much better served by purchasing a fempto-cell (some carries will provide one free of charge if you complain enough). This looks like a residential wireless router and basically acts as a limited capacity, short range cell tower.

Thanks for the reply. There carries in Canada all run 8501900 I believe. It never occurred to me to look specifically at the tower. No internet connection. Will be inside a metal trailer so shouldn't have oscillation problems but I figured a passive system wouldn't do much.