RF TX Research

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

https://en.wikipedia.org/wiki/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

https://electronics.stackexchange.com/questions/83052/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

https://www.youtube.com/watch?v=J3Hg2f7RL1A

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