[Shannon Hicks]

I deployed several sensor stations in a coastal estuary with brackish water in southern Delaware about 5 years ago. There’s no difference between those stations and any of the ones we put in fresh water except that we used titanium-body turbidity sensors instead of stainless steel. The other sensors were all rated for salt water use, and I used marine science installation techniques for everything else we did with those stations. These are the same techniques you’d need to use no matter what type of logger you want to use. There are plenty of resources online about how to install monitoring equipment in marine environments, and you can check with the manufacturers of the sensors you want to use to see if they recommend using their sensors in salt water.

[Shannon Hicks]

Thanks for the additional information, I appreciate you helping us out with this. I’ll send you a PM about what to do next.

[Shannon Hicks]

Sara is probably the best one to comment on the code aspect of your question, but hardware-wise, you might want to try a different pair of pins for connecting the sensor. D19 is used as the status pin of the Xbee socket, and is used in all of the code examples we use for radio, wifi, and cellular telemetry. D18 is kind of reserved for being used as either the card detect pin of the microSD card socket (if you enable SJ10), or you can use it for reading a trigger from the RTC via SJ6. So picking a pair of pins that’s totally free would be good in case you want to add telemetry or other features to your board. D4, D5, D6, D7, D10, and D11 are free, which is why I put them on the Grove sockets. The other digital pins that are available on the 20-pin header are bought out for compatibility with things you might put on a protoshield, but aren’t necessarily free for any sort of output or input from a sensor or other device.

[Shannon Hicks]

Yes, this is a known issue that I’ve seen with only a very few boards recently where we see those exact same incorrect voltage readings around the Q1 mosfet. I haven’t tried replacing parts to see whether it’s the mosfet or the D3 diode, but it’s definitely either one of those, or possibly both of them. I’ll see if I can experiment with some bad board this weekend and find the culprit. I’ve never been able to purposely cause a failure even though I’ve tried really hard to repeat the conditions and stress out the components with various hardware and power configurations. Were you powering the board from the microUSB port, the FTDI header, a LiPo battery, or a combination of those? And did you have any telemetry (radio, wifi, cellular) xbee modules installed at the time?

[Shannon Hicks]

We’ve completely run out of them because of all the requests for starter kits lately, plus our own flurry of logger assembly and deployment this fall, but as soon as we get more in stock we will be listing them for sale on Amazon as a separate item by themselves.

[Shannon Hicks]

Update: I shipped some kits to Amazon this evening, so they should be available again by this weekend or early next week. The LTEbee adapter boards will be a longer wait though.

[Shannon Hicks]

We are temporarily sold out of both right now but will hopefully get more in stock soon, though I don’t have an estimated date for that yet.

[Shannon Hicks]

Yes, there’s a quick guide to using the GPSbee listed on the Accessories page.

[Shannon Hicks]

I don’t think there’s an automatic way to show that in MMW, but for my rain gage loggers, I just have the Mayfly keep track of the cumulative total for the day, starting at midnight local time. And every 5 minutes, the Mayfly sends the cumulative total, and then at midnight, the Mayfly resets the total back to zero and starts again.

[Shannon Hicks]

This question has come up fairly frequently, most recently here: https://www.envirodiy.org/topic/minisd-card-slot/

We just haven’t had enough demand to warrant selling them separately since the majority of people buy the starter kits.

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