If the 3G modem is off then it wouldn't hurt the range, but if it is trying to establish a connection while you're scanning then I wouldn't be surprised if it had some effect.
How long are you scanning for? The longer you scan the more likely you are to pick up the beacons.
Just adding another BLE adapter is unlikely to increase the range, but having one with an aerial as near the outside of the box as possible and away from other electrical/metal parts would really help.
If you can find a Bluetooth LE adapter with an external aerial (they do exist, but they seem quite rare) that's likely to make a huge difference.
Espruino is a JavaScript interpreter for low-power Microcontrollers. This site is both a support community for Espruino and a place to share what you are working on.
If the 3G modem is off then it wouldn't hurt the range, but if it is trying to establish a connection while you're scanning then I wouldn't be surprised if it had some effect.
How long are you scanning for? The longer you scan the more likely you are to pick up the beacons.
Just adding another BLE adapter is unlikely to increase the range, but having one with an aerial as near the outside of the box as possible and away from other electrical/metal parts would really help.
If you can find a Bluetooth LE adapter with an external aerial (they do exist, but they seem quite rare) that's likely to make a huge difference.