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MB7UBA - LoRA APRS Digi/iGate
MB7UBA runs APRS over LoRA, located in Basingstoke, Hampshire (IO91kg). Also now running as an experimental VHF-LoRa APRS gateway.
Frequency: 439.9125 MHz
Bandwidth 125 khz
Spreading Factor (SF): 12
Coding Rate (CR4): 4/5 (ie. enter “5” for the CR4 coding rate)
This is the same frequency and parameters for LoRa based APRS across the UK.
The VHF-LoRa gateway function means packets received on LoRa are digipeated on VHF from MB7UBK, and packets received on VHF are digipeated on LoRa. This cross-band digipeating is done with the “directonly” setting in APRX for the VHF side, and there are rate limits applied more stringently on the LoRa side (though normal traffic for the area is well within these limits).
LoRa APRS Background
For those that don't know, APRS over LoRA is exactly what it sounds like: Automatic Packet Reporting System (APRS) packets sent using using LoRa radio modulation, instead of the more common FM modulation used in standard APRS.
A LoRa-only APRS map can be found at https://lora.ham-radio-op.net/, though packets from LoRa based devices are still found on common APRS sites like aprs.fi.
There is also a new map and database specific to LoRa APRS running CA2RXU firmware (iGate or tracker) is at https://lora-aprs.live/, and this has the added benefit of including signal quality data which is not usually forwarded over APRS-IS. See the help page for information on setting up your own device to feed this, it does not interfere with APRS-IS feed and can be operated alongside it with no problem.
Technical
The digi runs on a Lilygo T-Beam v1.2 with an SX1262, and uses the firmware by CA2RXU at https://github.com/richonguzman/LoRa_APRS_iGate. Tracker firmware, also by CA2RXU, for similar boards can be found at https://github.com/richonguzman/LoRa_APRS_Tracker.
There are plans to create some interaction with the packet node GB7BSK which is located at the same site, so you can interact with one from the other (within some limits, no large transfers over LoRa which would swamp the frequency!)