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  • Shannon Hicks wrote a new post 8 years, 2 months ago

    We are excited to announce that our Mayfly Data Logger boards are now available for purchase on Amazon!

    Mayfly Data Logger Board

    Mayfly Data Logger Starter Kit

    We’ve also published new information […]

    • Great to see these are now available. Unfortunately i’m in the UK and amazon doesn’t appear willing to ship this item internationally. Is there any likelihood that you will be able to ship internationally in the near future?

      • These look really promising. I second Davids comment though. I would very much like to test the Mayfly but Amazon are not allowing shipping to the UK.

        • We are aware of the availability issue for customers outside North America and are looking into different options for international sales.

    • Great! Looking forward to getting my hands on a couple of these.

      A basic question about power:
      Ideally, we would like to use 12V ~7aH AGM lead acid batteries to power the Mayfly instead of the 3.7V LiPo. We are planning to use the Mayfly for a pretty power intensive sapflux installation that requires small heaters to be powered directly off of 12V batteries. If we could use the 12V battery to also power the Mayfly that would be ideal.

      1. Is it possible to power the Mayfly with a non LiPo battery? What about a voltage >3.7? I know that the Uno can accept 7-12V, but I don’t see an obvious Vin port in the pictures of the Mayfly.

      2. I assume that the LiPo battery charging capabilities that are built in to the Mayfly are not suited for a Lead Acid AGM charging, correct? Do you have any suggestions for a low cost charge controller? We have used sunsavers in the past, but I’d love to hear any other suggestions.


      • On the top of the board near the FTDI header there’s an unpopulated 2-pin header for an Aux 5v input. Most people won’t use it, but I put it there for the experienced users who want the flexibility of different power options. I’ve been powering several boards like that lately, I’ll try to write about it on the Hardware section of the support page soon. The input voltage should not exceed 6v or certain components on the Mayfly could be damaged. While we could have included a regulator to handle higher voltages, it would require dissipating lots of heat, so in the interest of keeping things simple, we opted to limit the input voltage to 5v.

        An easy way to power the Mayfly with a 12v battery would be to use a 12v-to-5v stepdown converter with microUSB plug. There are many of them on Amazon for around $10-15. They are commonly used for connecting power in cars for dashcams and GPS units. Some of them also have an inline power switch and/or a fuse. I’ve been using one with a 12v, 18ah SLA battery and it works great.

        The charging circuitry on the Mayfly is only suitable for a lipo battery. You’ll need a completely different solar charge controller if you’re trying to charge a large capacity 12v battery. I can write more about that topic in another blog post that’s specifically about solar panels.

    • Neat! I’m looking forward to trying this out! I believe it will help me to get around some limitations of the proprietary logger I’m using and allow me to make sensor installations that would not be economically viable otherwise.

    • Is there any more info on availability in Europe ? Nothing on Sodaq website and I’ve emailed them but no response.

      • International sales options are complicated so we don’t have a option yet ,and I don’t have an estimate on when we might be able to announce something.