All is well

      Remember the pull-down resistor? The basic function of a pull-up(/down) resistor is to insure that given no other input, a circuit assumes a default value.

       Yeah. It was necessary. 

       The meter's electric field readings are appearing in the green & red LED array on the meter. I'm keeping them steady by holding the corresponding antennae, and I am turning the "fine tuning" knob to get the meter's LEDs to display a smooth increase in the strength of the electric field. The increase is captured by the photocells (with blue & red wires you see running to the breadboard), fed through the Arduino, and re-displayed in the brightness of the single, indicator LED (between my hands, on the breadboard). There are currently two photocells and therefore a three level translation of the meter's readings: off, dim, full brightness (no readings, low level detected, strong electric field present).

Why am I using an LED to... light an LED? I have tapped the meter's feedback, input it to the microcontroller, and condensed the range to one output. There is quite possibly a better way to do this by hacking the circuit at a point BEFORE the signal is split 12 ways in the LED array, but this was the solution I felt confident I could implement in the time frame (time crunch).

Next thing is replacing that indicator LED with an RGB LED.  This will translate something like blue --> purple --> red (aka off --> dim --> bright). Then I plan to split it to a series of RGB LEDs , to be sewn onto the Grandma Jacket.