goodbye world

By: kh6dk, 9:53 AM GMT on April 02, 2017

I read that the pws blog feature has been deprecated.
Goodbye World.

change log

By: kh6dk, 6:35 PM GMT on March 11, 2017

updated hoku:pwsRain
1. 5 minute buffers implemented with a minute rounding to the nearest five minute integer, then used as an index to a ring buffer, each bin summing the rain and wind speed

this allows a five minute baseline for calculating avg windspeed and total five minute rain.
Windspeed is reported as an average.
Rain is reported as a rate in inches per hour. Interesting. The rainTtl is a 24 hour total so you could watch the r...

rain gage jitters

By: kh6dk, 7:55 PM GMT on February 25, 2017

I found a source of the rain gage jitter: RF noise from a radio transmitter. I put in scripting to flag signals occuring within too small a time period to be real and found errors that coincided with radio transmitter activity.

Adding a .1uf bypass cap from the raingage signal line input to ground fixed that problem. The RF takes the short circuit through the capacitor to ground so the false signal does not reach the microprocessor.

instrumentation

extreme values (fixed)

By: kh6dk, 3:07 AM GMT on February 25, 2017

The arduino seems to be prone to jitters of some sort and I'm seeing extreme spikes in windspeed and rainfall, cause unknown. Installed couple of bypass caps at the digital/interrupt pin input to ground. In the meantime, I've put in software filters to trap extreme values, like 75 mph gusts and 45 fain gage tips in five seconds - raingage is in the arduino code..

note- these have been fixed in the electronics

Tipping Rain Gage Ideas

By: kh6dk, 6:07 PM GMT on February 24, 2017

Very tippy this gage. Mast mounting is not working out with too much flex in the mast. Vibration seems to the cause of false tips on the gage. A multiple tip event in a short interval e.g. 5 seconds and single tips in the adjacent time frames can be filtered as likely noise, but a single tip cannot without corroboration.

A mast mount is nice though. Maybe try the software approach and watch for false positives and negatives.

A single tip ...


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