RF TX Research

Quick links for calculating range of a given transmitter based on data rate, distance, frequency, antenna, etc.

Free-space path loss : Explains losses associated w/ radio waves travelling in free space (i.e. losses from radio waves travelling between antennas), based on frequency & distance

How to know (or estimate) the range of a transceiver? : Some explanation about Free-space path loss, also briefly touches on power requirement of receiver based on data rate, need to research this more though as it isn’t very clear

https://www.immersionrc.com/rf-calculators/ : Calculator that’s useful for figuring out parameters and range of an RF RX/TX system

Research:

This is the transceiver used by the https://oshwlab.com/jyesmith/expresslrs-gemini-tx board. It seems as if its basically https://semtech.my.salesforce.com/sfc/p/#E0000000JelG/a/2R000000HoCW/8EVYKPLcthcKCB_cKzApAc6Xf6tAHtn9.UKcOh7SNmg

with a PCB antenna.

Since we aren’t using a PCB antenna, the ELRS board could just use the IC (SX1280) directly and attach the output to a coax cable that attaches to the antenna.

How the JR module connects to the TX16?

Putting this video for good reference

ExpressLRS definitive getting started guide