I bought used outdoor WiFi access point for couple of coffees. At first I wanted to use only the housing for conversion of the TTN Indoor gateway to outdoor gateway. But after some testing and factory reset of the AP I found out it is working and could be configured as stand-alone WiFi MIMO AP. Usually such APs require infrastructure, or at least some management server.
This is short tutorial how to send data from sensor connected to The Things Network via LoRaWAN to Weather Underground. I will use Scidrom air quality sensor whic I developed for students in local school. Just a quick reminder the “AQ” sensor detects PM10, PM2,5 particles, air pressure, temperature and humidity and solar radiation in visible in UV spectrum. More details are available in older post.
“Special offer” came out for 5GHz antenna. It was posted on Polish web store Interprojekt, where I sometimes buy some equipment for long range WiFi point-to-point links.
Gold WiFi grid antenna, price 13 EUR
The antenna came well packed in carton with additional box for the feed. The grids were separated with paper to avoid scratches during transport.
The solar radiation shield is a low cost DIY device to protect temperature, relative humidity and other sensors from the weather, while shielding them from the sun for highest accuracy. Provided here are instructions and files. It require some CNC machinig, but then it could be assembled in minutes. It is made from plant pot saucers.
This simple Helical Antenna can be used for most LoRa (and other small wireless device) applications, where space constraints exist. The construction is simple, made from wound solid Ag plated copper wire taken from piece of coaxial cable.
Helical axial antenna for 868MHz
Two options how to use this antenna on the PCB modules
This is simple antenna for 868MHz built in 5…10 minutes. Take about 10cm of RG214, a plate of PCB with the copper at one (or both) sides. Remove the coax shield and inner dielectric on one side in length of about 85mm. You will cut this to proper length during SWR measurements.
Simple antenna made with piece of coax and piece of old PCB.
I will descvribe here the USB interface between the redio station and the computer which I recently developed and tested. This post is a continuation of the first part, where I described a simple interface for controlling two digital lines using the USB / Serial Converter, where I presented simple interface to control two digital signals (e.g. PTT and CW). This time I will describe an interface that combines more functions:
Controlling several digital (switching) inputs and outputs,
Interface for controlling the station via the serial interface
Audio input and output interface (sound card)
I had some implementation issues with the microcontrollers and USB virtual com ports, which I have described in detail in the previous contribution, I decided it’s better using the tested solutions. The block diagram of the interface is swhown in following picture: