Finished Opensource Raspberry Pi Gateway Hat (SX1301/8 base)

I don’t think the building is special. Old way construction. But anyway this week I will do some measurements outside. I think the antenna can be the turning point. Though would expect more distance even with 2dbi antenna. 64m is less than expected.

Will are you sure, the filter in the european version is correct?

You tell me about pushing distance to 1km with larger antenna. But I would expect with a larger antenna go even farther. Don’t you think is something wrong in my setup?

What other people report with the european version of the gateway. I’m not blaming gateway just making sure I’m not doing something wrong. I mean, setting incorrect tx power, frequencies, or something else…

I will try to do outside measurements this week. And will report back.

Thank you a lot for your support

With two 2dBi antenna’s and no real obstructions you should be able to do at least hundreds of meters. With line of sight multiple kilometers. However your measurements suggest there is some obstruction as there is that sudden 24dB drop.
Outside measurements with the current antenna’s would be very interesting. (Try to keep a line of sight, so no obstructions, for the best results)

I did thought that it might be the wrong filter, aka shipping wrong version,
For 868Mhz, I’m using B39871B3717U410 for SAW filter, and 0868LP15A020 for Low pass filter.
But the most confusing part is the sudden drop of RSSI for 24dB, which even if the filter is wrong, won’t cause a cliff like that, it will start a low RSSI then drop linearly with the distance. Another thing might help is to use one node as transmitter and the other one as receiver, then place the receiver same place as gateway to see if the situation still exists.

I can definitely sent you another one for replacement though, I keep some spare boards for such situation, if you sure that the gateway causes the problem, just PM your address. :wink:

Hi Will,

for now no need to do another shipment. Let’s see if everything is ok. But I appreciate your offer. I will let you know if we need a replacement.

Let me check the filter, try with another gateway (I ordered some) and even do node to node testing. Then we can see if something (replacement or just fixing) necessary. I normally tend to think problem is mine more than others. So I want to check first my setup and hardware.

I will let you know. Thnx a lot!

2 Likes

Hi @will3509111@kersing and all people that helped me. Blame me because I’m stupid.

My friend sent me a picture very clarifying
conectores_sma

The antennas I bought first time where SMA RP male!!! I connected them blindly to the gateway and powered it. I hope I didn’t broke anything because transmission feedback. I didn’t transmitted so I hope everything is ok.

The fact is that there was no connection between the SMA Female of the module and the SMA RP male of the antenna. So basically actuating as no antenna.

The new antennas I bought are correct. SMA male. But didn’t worked… This time, oh my bad luck, because the gateway ran out of power during the test, exactly in the same place where I did the others!!! So I thought it was not working. Same distance, and again, stupid me. I realized after because the logs…

I will redo all testing now and let you know. Anyway I bought some better antennas. 9,15dbi and some yagi 12 dbi directional to do more testing.

I will report back.

Thank you again.

4 Likes

Hi @will3509111,

Great job with the node! I love it. The gateway is perfect. I have still to modify software and get maximum of it but for now it’s more than enough. Thank you a lot for your support.

Finally everything is properly set and working. It seems that antenna placement is the most important setup that must be done.

The node:
Node

A street picture with the Torrelodones - Madrid (Spain) tower at the back:
Node_Street

And final antenna placement:
AntennaPlacement

TTNMapper

TTN Mapper seems to be finally working:
https://ttnmapper.org/special.php?node=lora-test-node&type=placemarks&gateways=on

1 Like

@will3509111 It’s working nicely.

Now we are testing in an industrial environment. The gateway is built with a 3G modem via USB (sim is missing today) but it will become available today or tomorrow again.

The distances now are impressive. With a half thumb antenna on pcb it’s reaching 1Km without any troubles.

https://ttnmapper.org/special.php?node=dfm-pcbv3-node-small&date=2018-09-19&gateways=on

The node is mounted inside the cabin of a dumper.

And it’s looking sooo sexy. We are looking forward to extract data from the machinery. It could be great if we achieve this.

Do you have still some spare boards to shell?

Best regards,

2 Likes

I recently encounter some problems with the yield, need some time to figure out the problem.
So it might takes a while for next run, I’m also want to change the PCBA factory this time…

1 Like

Do you mean it can be better? Great.

Tell us when you have it resolved. We will surely take a look on it.

Best regards,

I received a package at 22Km from a single channel gateway in Madrid. And I wonder how is this possible?

It also marked that gateway because the one we are running missed that package, maybe that’s related to the yield problem you found.
If you find something, please tell me because we can do testing that can help you.

Best regards,

The yield issue has nothing to do with the board
Because the problem is many board failed to lock PLL.

Hello Will. You really have a great board here. Any idea when it will be back in stock?

Thanks,
Louis

1 Like

I’m planning to do another batch later this year…
But the real problem is that I think RAK833+Breakout board might be a better way to do this.
RAK833 is sooooo cheap :worried:
RAK833 + GPS + PoE is a really good combination, for cost and build.

But I haven’t buy one for development yet,
their Taobao store doesn’t let me buy the one without USB.

For the current development, I have a new board for RPI Zero!
Finally I can squeeze a full config gateway into RPI Zero size hat :smiley:
IMG_5713_notext

3 Likes

Thanks for the reply! Although at $99 the RAK833 does work out cheaper than your board by the time you have added GPS and a PCB it costs more than your board by my calculations. Also, a big factor is your board is completely open source! Of course the RAK833 is a good future option and might become even cheaper as it becomes more widely used! It won’t fit on a Pi Zero like your new board though.:grinning: and your board just has an aesthetic appeal to it (it looks good).

Thanks,
Louis

I have both your board and the RAK833. Both are very stable but I had to add an external GPS module to the RAK. Also getting a board with PCI-e and suitable for a gateway ends up taking the price much higher. Performance wise, they are at par but total cost of ownership of a complete gateway is lower with your board as @LouisP pointed out.

While the idea of a full config gateway on the RPi zero is attractive, what options for internet connectivity does the RPi Zero provide?

@aizukanne The Pi Zero W provides wifi and Bluetooth built in and USB ethernet adapters are available for all Pi Zeros. However, you may be limited by the processor for some projects, instead having to switch over to a Pi 3.

I think the processor is not really limit here, the CPU usage is very low for pkg forwarder .
The main reason is to build a tiny GW able to take around with me, and setup a test bench.
Pair with USB to RPI Zero makes it alot portable :smiley:
image

3 Likes

Hey @will3509111 , I bought one of your new compact boards. It works great.

However there is a single LED next to the header rpi header, labelled D6, what does it do? I can’t seem to find the schematics for the board on github.

Hi @txf,
D6 is just a LED connected to RPI’s GPIO21 (High -> on), because there’s some space left, I wanna have some indicator that is RPI controllable, it may be useful if you are gonna program on RPI zero.

Sch and Pcb will on Github later. Recently I watched eevblog’s video about sch files drawings,
I think I need some more work to clear up the sch files.