arduino not picking up output from custom made lightning detector circuit

So i have this circuit that I've been developing here: |500x375 its a basic lightning detector sensor and alarm. The problem that I've been having is that the sensor does work (I've tested it with head phones and by plugging it into the audio port of my laptop.), however the arduino does not hear anything coming from the sensor. You can see I have it connected to the arduino in the circuit using an audio type input circuit (modified voltage divider), But it still doesn't want to work. Also, when i plug it into my laptop (the arduino) to test it with the serial monitor, it works just fine! But when I plug it into the wall it starts doing it again, weird huh? i'm just wondering if there is anything that might be wrong with the circuit and if so, how could i fix it? (also note that the arduino is running on the wall, and the sensor is actually running on a 9v, i have resistors in place in the sensor so that its output is less than 1v, just above when it picks up a lightning strike. Also, the ground is an earth ground.)

i don’t see any place in your schematic where you change the AC signal to DC and filter it so the Arduino can measure it’s voltage.

Paul

I can't figure out how the transistors are supposed to work. It may be due to the blurry lines and possibly confused m and M?

Where does the Arduino get it's 5v from..?

I can see the Arduino gets its signal input from the 100nF / 100k divider - which may be reasonable (similar concept to the DTR reset circuit on the Arduino board), however that also depends on several other things....

The input biasing of the pin voltage +/- so the ‘pulse’ is visible to the Arduino, the voltage of the pulse, and the pulse duration.

Your best bet is to watch the input with an oscilloscope set to one-shot capture, then with those parameters, you can work out what you’re looking for, and whether polling or am interrupt is needed to capture shorter pulses.