Re: 18650 batteries for QCX

HF
 

Hi Steve,
I also used 4 18650 cells for my QCX.  They're mounted to a piece of acrylic under the QCX, making a compact assembly.  I also included a tiny voltmeter along with a toggle switch so that it indicates voltage only when I want to spend the 30 mA needed to light it up.  There's a 1N4000 series diode in series with the batteries to drop a little bit of voltage because they can charge up to 4.2 V each which gives a voltage higher than the 16.0 V which is the maximum voltage one of the chips in the QCX (I forget which one) can tolerate.  Another switch enables me to short out the diode after the first several minutes of operation during which the voltage per cell drops to 4.0V.  It turns out that the run time is longer than I need; if there's a next time, I'll use the same circuit with 14050 batteries to reduce the assembly's mass.
I also charge the cells individually.
Halden VE7UTS

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