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  • I’m sharing some integration test results. I’ve been using a Vbat=4.0V threshold – that is under Vbat=4.0V it does sensor readings only, and stores the readings for later reliable data delivery.

    When the battery voltage is over Vbat=4.0V it POSTs the readings to MMW.…[Read more]

  • I’ve released a Mayfly image that interfaces to two depths sensors – an Insitu LT500 and Keller Acculevel – and pushes the readings to MonitorMyWatershed.org over a Digi LTE CAT-M1 modem.

    As a binary image, anybody can download it into a Mayfly, no programming experience needed. https://github.com/neilh10/ms_releases

    The per station…[Read more]

  • I’ve had a simple system soak testing.

    It has an Xbee WiFi, LiIon 500mA, measuring MayflyVbat and ADS1115 extVbat. When the extVat voltage is >=3.85V it will

    Logger dataLogger.logDataAndPublish();

    and when below <3.85V only

    Logger dataLogger.logData();

    I’ve used the 3.85 threshold as I found the Mayfly was resetting when the WiFi turned on…[Read more]

  • So just to add some more characterization measurements.

    I’m using a Mayfly Sn 20395, and attempting to characterize what range the readings from the Mayfly ADC Vbat are linear when it is only powered from Vbat.  I’ve put a resistor network on the extV to the LiIon batter, to halve the voltage to keep it within the Vcc range for the ADS1115.…[Read more]

  • Hi Matt, power is a challenge. I always think of those battery watches with a tiny battery in them. How do they do it.

    My take is this. a) what is the minimum energy its going to collect across the really low solar months  eg winter months  b) What is the longest I want the system to run for with no solar power – that is usually a storm of some s…[Read more]

  • I should note, that for real world solar panels, the power supplied by the panel is  dependent on the solar photons received. For a  slow change in power delivery some circuits have some strange behaviour.  I’ve had a Mayfly with an LTE  module, and a 2Ahr battery, and at sunset it started resetting. It continued resetting for about 30minutes unt…[Read more]

  • I’ve been using the INA219 and contributed sensorsTINA219
    I’ve used it for measuring a working Mayfly on the lab bench. For  field monitoring, I would think you need a coloumb counter ~ eg LTC2941 ~ I have an adafruit version but haven’t tried it.

    On the lab bench I have the INA219 on a separate Mayfly with console and put in in series with the…[Read more]

  • Hi Anthony, I would also be available for testing/helping integrate LoRa networking and I have some gateways. Wow great news to hear there is an implementation done.

    For my local SSU I volunteer as Industry Advisor, and for last years Engineering Capstone project a student used an Adafruit LoRa module on a raspberry pi pretty effectively.…[Read more]

  • Hello I’ve just had a request to quote for a number of water monitoring devices, each one includes a Mayfly. I’ve put on the response quote subject to availability of the Stroud Water Research Center’s Mayfly.

    Is it useful to be able to indicate potential demand?. Its a pretty typical thing for selling that there is a demand forecast.
    Some…[Read more]

  • Hi James, thanks for the agupubs reference – very nice to see the LiDar work.
    I had talked to a LiDar guy some years ago and they had said they didn’t think it would work for streams, but that ref is showing it very nicely.

    I’ve used 20mA depth sensors with Onset loggers, and had a couple of UL6a…[Read more]

  • Interesting idea for a secondary board, perhaps linked into the USB. I have heard it done before via the JTAG, but I don’t believe this is available for Mayfly.
    Possibly the biggest question on issues like this is power budget. If there was a reliable power budget for a linux SBC (beaglebone.org) it would be relatively easy.

    One area to track…[Read more]

  • Hey happy to contribute where I can.
    My wife and I started a trip in Hamilton with some friends in 1990. Spent 2 months traveling round NZ as part of a round the world trip. 🙂

    I have a fork of ModularSensors and focus on a small subset of sensors, scaleability through ability to build releases, download a defined binary of the code, and test…[Read more]

  • Hi James, great to hear someone else interested. I just got a “relative EC” working nicely and just gave them out to be deployed last week.

    The “relative EC” is to be able to measure stream disconnect. For the <<dry>> hot climate we have in California, looking to monitor when the stream goes dry.

    There is no reason why it can’t calibrated,…[Read more]

  • I have come up with an inline  plug-in circuit that will do the voltage shifting ( and  generate a +12V power and ESD protection)  that I’m working on, so just mentioning it here. If anybody is interested in the discussion we could take it to a separate thread.

  • Just an FYI,  as I understand the SDI-12 spec, the receiving instrument should receive 3.5V for a ‘0’ or space.   The mayfly port is only capable of supplying 3.3V – so it may work for most SDI-12 instruments, and is working for one SDI-12 instrument I’m using

    Typically with off-spec issues, things can work on some instruments and then not  on…[Read more]

  • There is a Mayfly Protoshield rev1 – but I can’t find if its for sale anywhere.

    I have one, and no plans for it right now so if you wanted it I could send it to you.

    The details are here, but no gerbers.  With gerbers it would be possible to order the base boards directly from o…[Read more]

  • Hi Matt,

    There is  a Mayfly prototyping board, which I should have used for one project, and forgot to 🙂

    I’ve prototyped with a basic 2×10 male to male header using wire wrap and soldering to the header. However I cut the 2×10 from a larger length I had, and it became unreliable pretty quickly.  For a cable maybe  0.05″ ribbon cable with IDC he…[Read more]

  • The response is great.

    For my WiFi/Xbee S6 accelerated updates 2min sampling update every 4minutes the ACK time over 700 POSTS time is between 200mS and  774mS.  All POST succeeding 1st attempt.

    For my Verizon/Xbee LTE at 15minutes sampling the ACK time is typically 5sec, very occasionaly about 1.5sec, and also 7Sec. For this test it delivered t…[Read more]

  • Over the last couple of days I’m getting very good response when using a WiFi, and the response time for 201 ack is sub 1second.

    This is a fast check with 2min sampling time, and SendX=2, so delivery every 4minutes. I get a response typically under 0.5seconds, and occasionally ~ 0.6Seconds. So for 1250 messages all have been delivered, 1st time…[Read more]

  • Hey good to hear.

    I haven’t been able to do a lot of testing, and I was out yesterday but I enabled a laptop computer to monitor one beta system overnight that is using verizon starting at 9pm PST. (though I forgot to add the power cord to the laptop and it turned off after 2hrs !!   ).    Its sampling at 15minutes, taking 8 readings, and pus…[Read more]

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