Override frequency being used on new install?

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Hi all, I just got v 2.3.11 running on two Lilygo TSS3 boards and was curious what Lora looked like and sounded like on a SDR so I set the SDR to 915Mhz but did not find anything. Later I did find it on 906.875Mhz (the override frequency)

Just need clarification on what the boards should be using.

Thanks, Dale

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You’re not the first to be puzzled by this. The short of it is, that frequency-slot 20 (906.875) is where you need to be if you want to communicate with others on an unsecured LongFast. It’s not required, but it’s the most likely place you’ll meet other nodes in-the-wild.

It makes antenna shopping a little difficult, since most are calibrated at 915mhz but we really care more about 906Mhz…even though most lean in the 915-920Mhz direction.

There’s a good reason to stay off of 915Mhz precisely, as smart meters, doorbells, and any number of household devices might make 915Mhz a noisy place to be, but it does seem a bit arbitrary to take us all the way down to 906. At this point, however, I think it’s more a function of convention. Asking every meshtastic user in North America to change default frequency-slots at the same time sounds…disruptive :sweat_smile:

Though I can see something like that possibly with a V3.0.0 release…though I’m no developer, just thinking out loud.

915 MHz (ISM Band)

The maximum output power for North America is +30 dBm ERP (Effective Radiated Power).

The band range is from 902 to 928 MHz.

There are 104 frequency slots defined with the standard radio preset LongFast. After factory reset the radio will be set to frequency slot 20 with a center frequency of 906.875 MHz.

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Thanks for the reply, it now makes sense. I also just changed to LongSlow and see it uses 905.3125Mhz as shown in the override frequency under Lora.

The LongSlow has a completely different look and sound to it when using the SDR.

I think it might be the “use modem presets” that locks the frequency in. I will play around with this when I make and test a private channel and might want to move it up in the band to a quiet spot.

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See also: Radio Settings | Meshtastic

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