Nilee,
The range on a 3810 is going to be roughly 150ft from the base. Some environments will be less and some maybe a little more depending on the construction of the building. But the answer your question.......no the range on the 3810 isn't great and there isn't anyway to boost that.

If your just looking for something to use in a couple of offices it would be fine, but not in a warehouse environment or large office complex.

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