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#* Initial tests suggest that this cell might work as a direct power supply without any additional regulation or boost circuitry
# A flexible printed circuit board
#* A flexible board can be folded over to connect to both sides of the coin cell, and to create two rows of opposing contacts which can be pressed together by the user to form a connection (i.e., pushbuttons)#* Initial idea is to use a board about 55mm x 75mm (roughly business-card-sized) which will fold in half lengthwise with a 5mm spacing between the top and bottom layers, yielding a device about 25x75mm 25x25x75mm (1x31x1x3"), containing the coin cell, 3 or 4 user pushbuttons, and the ESP12F module
#* A small piece of craft foam will likely need to be inserted into the middle of the device to provide stiffness, to separate the two layers, and to act as a spring to keep the user pushbuttons open when they are not depressed
#* These circuits could be inkjet printed at the college, or a traditional copper flex circuit production run could be ordered
#* The outside ("back") of the flex circuit could be printed with the pushbutton labels and other information, or these could be added in the form of a sticker.
# A connection scheme to attach the coin cell and ESP12F to the flex circuit
#* Z-axis electrically conductive adhesive transfer tape (3M type 9703) is one option, though the ESP12F circuit pads may be too small to permit reliable operation and sufficient current flow (approx. 1.5mm2, where the 3M documentation recommends 3.5mm2)
#* Alternatives to z-axis tape include wire glue or conductive epoxy, but these limit options for reusing/recycling the device