Weather Station

[tweiss3]

I have a weather station that I am trouble shooting my temperature reading with the manufacturer (I think the board is dead because it is not 158 degrees out). I was looking at the specifications and troubleshooting steps, and it caught my eye that the station uses 433MHz to communicate with the display, right in the middle of the 70cm band.

1) How did this get approval to use 433MHz for communication?

2) I unfortunately have this station 12' above my UHF quarter whip on ground plane and only about 18" horizontally. I think being directly above, its in the middle of the null and not causing the issue. The remainder of the sensors work flawlessly, its only temperature that is off. I'm not causing my own interference am I?

Thanks,

 

[Thunderknight]

We (hams) are secondary on 70cm. The station is probably either Part 15 or ISM anyway.

If it's showing 158, my guess is that might be the max reading of the sensor/system and the controller/display is defaulting to that value either due to no data or data being out of bounds.

 

[tweiss3]

We (hams) are secondary on 70cm. The station is probably either Part 15 or ISM anyway.

If it's showing 158, my guess is that might be the max reading of the sensor/system and the controller/display is defaulting to that value either due to no data or data being out of bounds.

Idk how I missed or forgot that 70cm was cohabitated.

As for the sensor, yes, I think the sensor itself is bad causing the odd reading. Just confirming I wasn't the cause of my own problem. I did operate 444.55+ last night for a net, so pretty far from 433 to cause an issue.

 

[Thunderknight]

If it was stray RF, two things could happen:
Odd readings while transmitting...either from the RF front end on the receiver being overloaded, or from RF getting into the sensor's circuity.
Or, permanent sensor damage from the raw RF power.
In the RF getting into the sensor case, being 10 MHz away wouldn't really matter as that is not frequency selective circuitry. If you have had this same setup for a long time, it's probably not stray RF.

 

[vagrant]

Mount a weather station about five feet above the ground and away from a building and things. People are usually around that height above the earth as well and not floating above their roofline.

Also, if you would not put your head that close to your antenna when transmitting, avoid putting electronic devices there as well.

 

[Thunderknight]

Mount a weather station about five feet above the ground and away from a building and things. People are usually around that height above the earth as well and not floating above their roofline.

For temperature, it's 2m above natural ground, in the clear, with radiation shielding (Stevenson screen) to prevent the sun from overheating the sensor. Not always practical for the residential install...but keeping it in the shade, not over pavement (or the like) are important.

The standard measurement location for anemometers is 10 meters and 10x the distance to any obstacles. That's hard to meet in a typical residential application, but the higher the better up to that point. You want to be clear of obstacles and affects from buildings. If you put it at 5 feet and the house is 2 stories and only a few feet away, you'll never get an accurate wind speed and direction because the structure will affect the airflow.

 

[spongella]

I

For temperature, it's 2m above natural ground, in the clear, with radiation shielding (Stevenson screen) to prevent the sun from overheating the sensor. Not always practical for the residential install...but keeping it in the shade, not over pavement (or the like) are important.

The standard measurement location for anemometers is 10 meters and 10x the distance to any obstacles. That's hard to meet in a typical residential application, but the higher the better up to that point. You want to be clear of obstacles and affects from buildings. If you put it at 5 feet and the house is 2 stories and only a few feet away, you'll never get an accurate wind speed and direction because the structure will affect the airflow.

My Accurite wx station has a solar cell that runs an internal fan to keep the temperature sensor from being affected by the sun. Other models many not have this though.

 

[tweiss3]

If it was stray RF, two things could happen:
Odd readings while transmitting...either from the RF front end on the receiver being overloaded, or from RF getting into the sensor's circuity.
Or, permanent sensor damage from the raw RF power.
In the RF getting into the sensor case, being 10 MHz away wouldn't really matter as that is not frequency selective circuitry. If you have had this same setup for a long time, it's probably not stray RF.

It's 45W max.
Station was installed mid December 2020, had no problems till a week and half ago when the snow hammered us. I just got up on the roof last night to try their "steps".

Mount a weather station about five feet above the ground and away from a building and things. People are usually around that height above the earth as well and not floating above their roofline.

Also, if you would not put your head that close to your antenna when transmitting, avoid putting electronic devices there as well.

I did follow the weather.gov guidance for personal weather stations, given I have a pond, mature trees and pavement. Its 24' AGL, 7' above the roof, and shielded. Still the best spot I have available.

Also, per the RF evaluation, it's not an exposure level that would be of concern to a human in an uncontrolled space.

For temperature, it's 2m above natural ground, in the clear, with radiation shielding (Stevenson screen) to prevent the sun from overheating the sensor. Not always practical for the residential install...but keeping it in the shade, not over pavement (or the like) are important.

The standard measurement location for anemometers is 10 meters and 10x the distance to any obstacles. That's hard to meet in a typical residential application, but the higher the better up to that point. You want to be clear of obstacles and affects from buildings. If you put it at 5 feet and the house is 2 stories and only a few feet away, you'll never get an accurate wind speed and direction because the structure will affect the airflow.

It's in a good spot to get accurate wind, rain and pressure measurements. It's also shielded so it shouldn't be as big a deal with the solar reflection from the roof.

I

My Accurite wx station has a solar cell that runs an internal fan to keep the temperature sensor from being affected by the sun. Other models many not have this though.

Mine is Acurite, with the fan.

I'll continue working with the manufacturer to get it fixed. My instructions put me on the roof again, and pulling the sensor for pictures.