Receiver online but range is very low or zero

Regardless of whether your installation is new or has been running for a while, the following applies to all

1. Check that the connectors are tightly connected to both the antenna and the receiver. 
2. Have you checked the antenna, the coax, and the connector for moisture, corrosion, or other damage? (mostly the case when range drops having been pretty good previously)
3. Make sure the antenna is located as high as possible with a 360-degree horizon and above the roofline. (mostly applies to new installations)
4. Lastly, check if there are mobile GSM transmitter antennas nearby. In which case you might need a filter.

If you still need any assistance, do let us know.