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Bridges B Bridges ABridges Combo

It is hard to compare dBm and mW. Here is some help: 30dBm is exactly 1000mW or 1 full Watt, 20dBm is exactly 100mW, 17dBm is about 50mW, 15dBm is about 32mW. Every 6dBm distance effectively doubles. dBms are lost are the following rate:

glass or window 2dBm
Drywall Wood wall 3dBm
cinder block or concrete wall 4dBm
Metal door in brick wall 12dBm
1/2 inch chain link or mesh fence total block

dBm <-> mw calculator can be found [here]:

Antennas increase dBm by increasing receive sensitivity which in turn increase range.

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