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Can we make onboard antenna external?

mrnams

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Hello,

Sorry 1) if this is wrong place 2) Dumb question.

I am working on smart irrigation project, I have Arduino connected with 4 sensors and 1 actuator, Arduino collect data and send to ESP32 using Reyax RYLR896 Lora Module connected to it.
I keep all PCBs in one waterproof box, but this cause network loss with other Lora node, so I decided to remove antenna from RYLR896 and install it on tall pole and connect it to RYLR896 by single wire, will this, work?

This is original RYLR896
Original RYLR896.png


This is what I planned to install antenna
Modified RYLR896.png
 
Yes, the wire has to be co-ax, you can't use normal wires. The co-ax needs to have its shield connected to the module ground as close as possible to the antenna connection. I would suggest RG174 cable is suitable.

You will undoubtedly get better results by using a proper external antenna. The helix is suitable for close range work but you would get far better coverage by using a purpose made antenna for the frequency you are using.

Brian.
 

    mrnams

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Yes, the wire has to be co-ax, you can't use normal wires. The co-ax needs to have its shield connected to the module ground as close as possible to the antenna connection. I would suggest RG174 cable is suitable.

You will undoubtedly get better results by using a proper external antenna. The helix is suitable for close range work but you would get far better coverage by using a purpose made antenna for the frequency you are using.

Brian.
Tons of thanks for quick and detailed reply
 
you, unfortunately, do not show the backside of the board.

IF the backside has a metal ground plane, then you can replace the antenna coil with an SMA edge connector. then run a 50 ohm coax cable to your tripod. at the tripod, you have to have a board with a ground plane of approximately the same dimensions, with another edge connector and a 50 ohm microstrip line that you solder the coil antenna to. without that ground plane, the antenna will not be even close to working properly.
 
Antennas are generally used "outside". Placement considerations include desired field of view and the losses associated with the particular connection (transmission line).

Your sketch shows an elevated position and cabling of up to 11 meters. That will have insertion loss and be significant so check what you can tolerate.

As a guess, if you can find a watertight box that is RF transparent you could put the PCB on the pole and then only have data lines to bring down rather than the more complicated (and possibly lossy) RF transmission lines.
 
Not sure what is the material of that waterproof box, assuming it is not metal? Then maybe the loss of that 5m cable + mismatch loss cause by the soldering is bigger than the attenuation cuased by the box...
 

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