LoRa-concentrator

So, its finally back from PCBA!

Also added PoE header to support RPI PoE hat!

I love matte black so much :D

By moving to a 4-layer board, I can finally build a full setup LoRa gateway (2xSX125X) with LNA/PA for Raspberry Pi Zero!

So my multi-channel high altitude balloon receiver is pretty much  finished, it's time for LoRawan!

Ver1.5 will have PA/LNA on board with RF switch so only one antenna is needed.

Ready for some testing!

Since I can add my own LNA+Filter under antenna, I've designed a small board using MAX2640 and a SAW filter, LNA is power by RF Bias. I left a inductor pad on Gateway  so that I can power through RF cable line.

Newer version using SKY67150_396LF, which have a much better NF

waiting for my new Filter and amp board! 

I've order about 25 boards from PCBA factory, and it just arrived!

And I'm selling this board on Tindle, note that it is 915Mhz version.

Also note that I've updated Github, new version of  PCB files for RPI+RPI Zero is up.

Finally.

So it is working!!!!!!!

note that since I removed channel A, hal testing will print error regarding channel A 

So I solder the SX1301 and 1.8V step-down, but i ran out of SX1255 and forgot where my previous board went. Thus testing SX1301 without RF frontend while waiting my new order.

And it seems working, no longer stuck with calibration firmware error.

So... it's almost a year for this project.
Quite a lot happened this year, LoRa community has grown pretty fast,
even SX1301 datasheet is now open without NDA.

I'm still not able to make the first board working though, after re-soldering and testing, again and again, so I stopped for a while.

I think I might overheat the chip though.
I've checked the SCH with datasheet, no such big difference found.

So I'll try again with version 2, designed for Raspberry Zero
Added step-down for 1.8V supply, GPS module, 
but removed RADIO_A because of the board space and layout reason.
Also ordered new SX1301, maybe also a Concentrator from others to compare.

Hope this works.