This is a small, cost-effective 915 MHz band pass filter with RF adapters for Helium Miners.
The filter is centered at 915 MHz with a typical insertion loss of 2.5 dB in the pass band 902-928 MHz. It has excellent out-of-band rejection specifications. Rejection at 880 MHz for instance, is typically greater than 40 dB.
The filter also provides power handling of up to a maximum +24 dBm with an operating temperature range of -40C to +85C.
The frequency range of this filter complies with miner frequencies US915 and AU915.
The kit includes two RF adapters to connect to a Helium Miner.
Reduction of Radio Frequency interference for Helium Hotspots*
Frequency Typical Insertion Loss
DC-800 MHz 50 dB
800-880 MHz 40 dB
960-1080 MHz 32 dB
1080-1500 MHz 40 dB
1500-3000 MHz 25 dB
*A Helium filter is beneficial if your Helium antenna is on the top of a building, tower or other location where there are LTE or cellular transmitters. It also benefits certain miners that have omitted an internal SAW filter to save hardware costs. In many situations a filter may not benefit performance. In fact in some situations, it will degrade performance.
After adding a filter between the antenna and miner, we recommend leaving it in there and running your experiment for at least a week. The Helium network is very unstable and the frequency of beacons from neighboring hotspots can vary greatly for many different reasons. A week gives enough time to assess if a filter is beneficial or not.