Posts: 5.357
Threads: 333
Joined: Apr 2014
Weather Station: WeatherDuino 4Pro
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Interesting test!
How many walls between outside and the RX unit?
Is the RX unit at ground level?
Posts: 222
Threads: 32
Joined: Jan 2015
Weather Station: Mata dos Medos Weather
Country:
Just to tie a couple of loose ends:
1) I did test the TX without antenna with the device placed in the roof and it seemed to work well enough.
2) I redid the mobile RX test once I had the TX+antenna placed in the roof and I got a range increase to around 100 meters, most notoriously with a couple of houses as an obstacle.
Posts: 5.357
Threads: 333
Joined: Apr 2014
Weather Station: WeatherDuino 4Pro
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Thanks for those well documented tests in a real situation.
The best I had achieved until now is around 150m to 180m. TX unit in the roof (my house is in a high place), RX in line of sign, but without any obstacles between.
Posts: 155
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Joined: May 2015
Weather Station: Palmy Weather - Palmerston North NZ
Country:
My work has just started selling 433MHz antennas, I was shocked at the size however. In the photo attached you can see the size difference. The top antenna is 100mm long, and is what I am currently using however what my business is selling is only 40mm in length with an apparent 13dbm of gain. I can not seem to find the gain information for my origonal larger antenna, but it was sold as a 433MHz.
[attachment=608]
It suppresses me how different sizes can be used for the same frequency, but I guess results on distance will vary.
I will give this little guy a go and see what happens with my weather station, if it works, it would be a nice little addition and fit well inside my housing. My only concirn is maybe the size is too small for the power the transmitter module is putting out and could burn something out.
Posts: 5.357
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Joined: Apr 2014
Weather Station: WeatherDuino 4Pro
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If you remove the plastic on both of them, I'm almost sure you find the same thing inside, just a very small coil.
if you gonna change your antenna, and you are planning attaching it directly on the RX board, try a model with a right angle connector. For a unit placed on the roof, I always get better results with the antenna in horizontal than in vertical position, and don't forget that 433mhz is very directional, the better you position your antenna regarding the position of your RX unit, the better the results.