Cheapest reliable barometer

[rogerthebodger]

Same little chip works with openplotter on a Rasperry pi which *should* be able to output nmea 2000 with a car can-usb dongle.
But quite possibly not much use to you as it takes about 0.3a and would need to be on all the time to get the trend.

https://sailoog.gitbooks.io/openplotter-documentation/content/en/can-usb-stick.html

Here's an interesting project using a RPI to measure temp, humidity and pressure and sent it to a server.

https://circuitdigest.com/microcont...tion-to-monitor-temperature-humidity-pressure

 

[GHA]

Here's an interesting project using a RPI to measure temp, humidity and pressure and sent it to a server.

https://circuitdigest.com/microcont...tion-to-monitor-temperature-humidity-pressure

The openplotter image for the Pi actually has a lot of this capability built in, there's a MQTT tab (low bandwidth way to transmit data) so should be easy to send any nmea or signalk via MQTT to thingspeak or thinger or one of the many internet of things sites around now to display online.

 

[pragmatist]

We've just added a barograph to Skipper's Mate - it's showing a rather low figure as our office is 700ft above sealevel and we haven't taken the sensor to the boat yet. (Add 21.5mb to for the equivalent at sea level.) The software is FOSS (Free Open Source Software) and, like an earlier post, it uses an Arduino, a BMP180 plus Bluetooth and a 12V/24V step-down to power the Arduino. You can see it, plus Sans Serif's live graphs for voltage, temp/humid/dew pt, plus security cameras from the Live Feeds page - https://www.skippersmate.co.uk/livefeeds.html

Penny

 

[anoccasionalyachtsman]

I have an "Auriol" branded weather station which I bought at Lidl. It does proper pressure (in mbar) as well as a five-stage bar graph pressure history. It also does inside and outside temperature, radio-controlled time and high water times for a small range of European ports ... "Glasgow" works quite well for me.

Bought one on your recommendation (!) and it's just arrived. I've got it set to London, but a) it seems to be stuck on 'Lo', and b) the times shown bear no relation to tidetimes.co.uk. Not a big deal, because I'll just use a custom difference from what it says to Portsmouth, but just wondered if you'd seen similar and managed to correct it. There's nothing helpful in the manual as far as I can see.

 

[fergie_mac66]

Haven't read all thread , so sorry if someone's mentioned this, many android phones have a barometer built in, look for barometer apps you can change the scales calibrate and record as much history and change the frequency of the recording
I dont have a sim in my old android phone so I use that . It can be calibrated as an altimeter .

 

[fergie_mac66]

I havent calibrated this phone for 6 months and the blip is when i went up. Big hill earlier today

 

[Yngmar]

Looks like just what I need except with a nmea2000 output. Can I be bold and ask if you have the instructions for the project as I would love to give it a go?

Haven't documented anything about mine, but there's a good intro on the BMP180 here: https://learn.sparkfun.com/tutorials/bmp180-barometric-pressure-sensor-hookup-

The LCD is very widely written about - just make sure you don't ignore the contrast control or you'll see nothing. The code is super simple - tell the BMP180 library to calibrate to sealevel, read the pressure and temperature and push the values to the LCD (or whatever output you prefer).

 

[djyacht]

Check out Aldi, 16th March. Guaranteed 3 years £19.99