Only get packages really close to the gateway

Hey guys,
I’m using lora to send information from an MSP430 to a gateway (RAK 7258), but it only works in tiny distances (like inches!!!).
I don’t know if its some problem with the configuration of the gateway or the MSP430…
Here’s some pictures of my configuration.

I’m using 433Hz. BW 125Khz…

If messages are getting through but only when close together, the first thing to check will be the antenna on both gateway and device.

At worst, for 433MHz an piece of wire 16cm long will be good as a simple test over 100’s of metres.

I got 500 meters in town, with a lot of buildings is that good?

Are you sure that your node hardware and software are both actually suited to 433 MHz?

IIRC, 433 MHz uses the low RF port on the sx127x chips, unlike 868 or 915 which uses the high.

If your node isn’t designed and properly configured for 433 from start to finish, the effect could be that an antenna soldered to your board is still not functionally connected to the radio transmitter.

I made a lot of changes, and I was able to get about 500 meters with a lot of houses and buildings around, but this is not enough for me. Both node and gateway was at ground level (my friend was holding it for me), if I place it a little bit higher do you thing I can improve this distance?

Probably easier to try than have us guess :wink:

It’s not just about height, it’s about what is in between. Put something on a hilltop or a tower, walk or ride your bike or drive a substantial distance away, and if you can see the location of the gateway there’s a pretty good chance you can get a signal through. If it’s hidden behind trees, maybe. If it’s hidden behind buildings, probably not unless you are very close.

For sure hehehe
But let me ask you a question…
I have some doubts about SF and bandwidth …
Is there any way of increase the coverage area by decreasing the bandwidth or the SF?
I’m using SF10, but I also made some tests with SF12… wich is the best?
About the bandwidth, 125KHz is the limit? Or can I decrease?

Probably easier to try than have us guess :wink:

didn’t help :confused:

Not sure what this means - people learn best by trying things or reading about things rather than having the answers just provided for them - what are the supported DR & SF for your region?

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of course, i’ve been trying things for the last 3 months, and i’ve been reading a lot of stuff too.
Nevermind. thanks for the help

You never said this nor have you told us what you have tried.

If you’ve burnt up three months of your life, you’ve got some significant skin in the game.

First thing, get a known good node, something that’s already been tried & tested, to make sure your gateway is good.

Second, go to a known good gateway to try your node.

Third, build something simpler with off the shelf components - Arduino + UART based radio module. Or if you still have some patience left, Arduino + a radio chip via SPI like GitHub - descartes/Arduino-LMIC-example: Known good Arduino ATmega328 + LoRa chip LoRaWAN node which I can help with in detail.

I did ask a question about your regional settings so I could answer your question about SF10 vs SF12 and the data rates but you haven’t answered. Where in the world are you?

And exactly how far away from the gateway do you want your device?

I can get 100km LoS out of SF11 20.8k DR on 433MHz with the transmitter using a 16cm piece of wire as an antenna and the base station with a mag mount aerial, so a few km with well placed kit is entirely possible on the ground.

I’m from Brazil, and for everything I know, there’s not a regulation for that here. I’ve made some tests today. I placed the gateway about 4 meter above the ground and drived for about 850 meters, and i got the message with “rssi”: -99 and “snr”: -3. I’m using this antenna in the photo. I’m using as node a MSP430 and as a gateway a rak7258 and a self made gateway using ESP32. Both esp32 gateway and node uses the RA-02 SX1278 433MHz. I tried with SF12 today. I asked about the spreading factory because I only got time to made more test in the weekend…
Do you think I’m going into the right way?

I would be satisfy if I could get 7 km (in a place with no buildings). Do you think it’s possible with this antenna?

The test I made today was in my neighbourhood. Check it out.

The point of SF is that the higher ones make each element of the signal last longer which gives more opportunity for the signal to be detected at the receiver.

So theory has it that you will get more range from a higher SF, but there are many other variables in the mix, not least the quality of the antennas involved. You could compare what you have with the range on the RAK website as it is very easy to get something from Amazon or other online supplier that does not do a good job.

So sadly we are back to the original “give it a try” response. Do you have mobile internet - if so, drive to somewhere like Santo Antonio hill and try your device, look at the gateway information and you can run tests with different SF settings in ABP mode in real time and see the results on the TTN console.

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No, you are not.

First an SX1278 is entirely unsuitable for a gateway, that is a node radio only.

Next your antenna is far too small for long distance work, especially for the gateway.

Then keep in mind that the slower SF’s require a different mode of radio operation on the node end, and a more stable oscillator - do you have these?

The OP does own a RAK7258 but I was remiss in pointing out that the home made ESP32 gateway isn’t suitable or helpful. However he does own the only two gateways for many kms so getting Antonio started seems a fair balance. It’s up to him to choose to compare what he has in the way of kit, and particularly antennas, with what is sold commercially.

The hard bit is getting the scientific process in to the engineering mindset - so many variables - until I happened to look on Google Earth, I had no idea there were so many high rise buildings in a town in a middle of Brazil!

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