Kenwood TM-D710 in weather station modeRadio amateur station PA1JIM also has an amateur meteorological measurement station. Measurements are done by means of a Ultimeter2100 weather station by Peet Brothers.

APRS

Around 2012 I became more and more interested in APRS (Automatic Packet Reporting System) and it’s capabilities. As a relatively new radio amateur I have not experienced packet from the heyday. Despite the fact that APRS is based on the simple AX-25 packet protocol, the applications within APRS are quite diverse.
I soon got underway with APRS objects and positioning of mobile radio application. I read about the possibility of sending weather telemetry data via APRS. For a long time I desired to also have the ability to post such a weather station and run. Simply because I find the idea of being self-sufficiency intriguing and running your own weather station adds to that idea.

Weather Station

In June 2015 my weather station finally arrived! Placing the anemometer was the easy part. I simply put a branch in the antenna mast for the anemometer. Placing the temperature sensor was slightly trickier. There’s nowhere around the house a place where there is always shade throughout the day. The chimney seems the best place. However, there is some morning sunshine. There was the need for a UV-shield so the measured temperatures are reliable. I’ve made my own UV-shield.
In November of 2015 the final addition for the weather station arrived: the WSF-47000, a combo of a rain gauge and a humidity/temperature sensor in a UV-shield. This combo replaced the original temperature sensor with it’s home made UV-shield.

Weather to APRS

Anemometer and temperature meter are approximately 9.5 meters high and hang freely attached to the antenna mast. The obtained data is regularly compared with those of the neighbouring Royal Dutch Meteorological Institute (KNMI) and seem accurate.
First the collected data was sent to a Kenwood TM-D710 radio via a serial link that transmits the data via the airwaves 144.800 MHz APRS. But after time went by this setup didn’t proof itself stable. The time stamps on packets from the weather station and the time from TM-D710 seemed to lapse too much which resulted in the TM-D710 not sending out any APRS-packages any more. After turning the clocks right a few times I was out of patience. So I bought a RaspberryPi and use WeeWX as processing and APRS-gateway for the weather station. No more clocks out of sync. WeeWX actually corrects the time of the Ultimeter!
Check the weather data at the source!