September 22, 2008
about a year ago
I would like to recommend (suggest) a pcb redesign of this board so that it will include the two smalls hole that the SF1 filter require.
And a second thought is to (optional) include a RJ45 socket. In case someone wants to physical place inside a radiation shield, and if used with the USB weather board, then i can also suggest a RJ45 socket addition at the USB weather board, in order to connect to.
about a year ago
Looking for the way the rain gauge works, i think there are two options:
a) Each change a tiping bucket makes a short pulse, so with the pull up resistor we have, it makes a pulse from logic 1 to logic 0 and back to logic 1. Then the circuit we all use is correct.
b) Each tiping bucket position makes either logic 1 or logic 0. So, since we use a pull up resistor, we count only the change of logic 1 to logic 0. After a change from 1 to 0, and after more rain, the gauge will change to logic 1 (this will NOT increase microcontroller’s rain counter) and then, after more rain, the gauge will change to logic 0 (this will INCREASE microcontroller’s rain counter) .So, we are only counting changes of logic 1 to logic 0 and NOT counting changes of logic 0 to logic 1. Do we miss some rain, this way?
The question: If this is the way to gauge reed relay works, why not connect the rain gauge to a microcontroller port with interrupt on change capability and count both changes???
I am asking that, since i also saw the recent change in the Sparkfun’s weather shield board software (after a user’s real work measurents). I mean the increment of the rain value of each pulse.
So, with which way it works?
about 2 years ago
I would like to come back to the issue of wind speed sensor.
Since the sensor makes two pulses for a full revolution, there was a small issue about the way of calculating wind speed.
I mean either use a pulse or two pulses for calculating a wind speed of 1.492 MPH (or 2.4 km/h).
So, is there any verification about this?
about 3 years ago
So, my sensor is not broken. It is normal to make two pulses per one full circle.
Your answer made me relief!
For the history:
For anemometer i used 10K resistor pull up and a 10nf to ground for filtering.
For wind direction i used 8.2K resistor pull up and a 10nf to ground (all in 3.3V circuit).
Both are working very good!
I am recommending these sensors to anyone wants to make a DIY weather station!
I noticed that wind strength meter makes two contacts (pulses) for each full circle.
I was thinking maybe it should make a contact (pulse) for each circle.
It can be checked even with the multimeter.
Is that correct? Or mine is broken?
No public wish lists :(
Forgot your password?
No account? Register one!