Meshtastic

Relationship between channels and frequency/SF?

I have a few basic question on setting the channel.
I am using firmware-tbeam-US-0.7.11.bin
and android 0.7.93

Can the lora frequency be set (I assume it is currently fixed 915MHz on the US firmware) ?
This would be to allow multiple channels frequencies, in-addition to the channel name.

Does the channel options set a Spread Factor ?
Do all devices display what freq and channel option (mode) they are set to ?

I have a follow-on question … concerning what frequency does the country builds
actually specify.

In the master readme.md it has various supported hardware depending on what
country. This leads to a selection of which compiled firmware to choose based on
several supported countries.

This maybe follows the https://github.com/meshtastic/Meshtastic-device/blob/post1/docs/radio-settings.md

Then the code in https://github.com/meshtastic/Meshtastic-device/blob/post1/src/mesh/MeshRadio.h
seems sort of related. It defines variables such as define CH0, CH_SPACING, NUM_CHANNELS

Questions…

  1. Does the device start using frequency CH0 ? (example for US 903.08f // MHz )
  2. Does changing the android “channel name” (from default) change the frequency to the next frequency “channel” ? (example US 903.08 + 2.16 = 905.24 MHz )
  3. Is the frequency “channel” related or unrelated to the android “channel” ?

I saw a post somewhere … but can’t find it… about changing the android channel name to append it to reflect the actual frequency/mode…

I get lost trying to follow the flow of the various variables.

EDIT: changed the links…