US915 uplink uses EU868 868.3

Good Morning,

I have 2 gateways connected and configured in TTN: one for EU868 and the other for US915. When I want to join a Lora module with the gateway US915, the module send the join request to the EU868 gateway.

I have check the firmware of the Lora module and it is for 915 MHz.

I try to set by firmware de channel frequency to 915 MHz, but is still not working.

Can anyone help me?

Thank you in advanced!

Turn off the EU gateway??

Where are you that both bands are legal?

If I disconnect EU gateway, I don’t see any join request in the US gateway. Yes, both bands are legal

I think we’ll need model names / numbers for gateways & devices to figure this out further.

I am using LoRa module S76S from AcSip. About gateways both, US1915 and EU868, are sentrius RG1xx Laird

Presumably you are sending it the wrong commands, or using the wrong firmware.

Where are you that you claim both bands are legal?

I have two different firmwares: one for EU868 and other for US915. Commands are the same for both bands presumably. I have check that the firmware is the correct.

I am in Spain.

https://www.thethingsnetwork.org/docs/lorawan/frequencies-by-country.html suggests you should be using EU868 only.

At least for TTN (which is what this forum is exclusively about)

So if I want to try out some Lora modules to know if the firmware is going to work in other countries like USA, i can not do it because of TTN?

In another occasions we have no problem to transmit in 915MHz with US915 gateway. Is only for testing, I am not going to keep modules transmiting continuously.

TTN cannot really tell where your gateway or device is. Using a non-EU868 gateway on ttn-router-eu may cause weird problems with wrong channels for downlinks, but in your case it’s the uplink that’s using the wrong frequency. For that, the device is to blame: devices just transmit, they don’t know what gateways are around.

You’ll have to check the firmware again.

And make sure to keep at least a few meters between device and gateways: even if the device is using US915, maybe a EU868 gateway erroneously picks up something due to overloading of its receiver? That surely is the case for channels within a single frequency plan, when devices are too close; I don’t know if the same problem could show between different frequency plans. In that case your US915 gateway would be broken, as it’s not receiving anything. Make sure to look at the logs of your gateways; don’t only rely on TTN Console.

Generally in the EU you are not allowed to transmit on those frequencies at all. For testing you need to connect the gateway and the node using antenna cable and an attenuator to make sure you are not transmitting any signal on these frequencies as that are generally reserved for mobile phone operators.

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