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Reply To: Case for Lower Threshold Voltage on Mayfly Stations

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2021-03-02 at 4:44 PM #15188
Jim Moore
Participant

    Couple of clarifications:

    • The discharge is a fixed load of 22Ω so ohm’s law works!
    • My question is why is the Mayfly station drawing less and less current as it approaches 3.3 Volts?  Yet the 4G modems continue to work and upload the data.
    • I believe that Shannon said that some older sd cards tend to cause current draw during sleep mode.  Maybe this is what is happening.
    • Matt- I am interested in your coulomb counter?  Where can I get one or is it home brew?
    • I have learned that not all Li-ion batteries are equal in terms of stated Ah capacity.  I bought some from Amazon rated at 4.5 AH yet they were less than half the size of the 2.5 Ah batteries I got from Adafruit!  And the JST connector polarity was reversed!

    Cheers

    -jim