I suppose instead of connecting to the LED it will connect to A3 on the Arduino for example but I'm having a hard time making it work. enter image description here I don't know which point on the circuit should be connected to which pin on the Arduino. I seem to get values alternating between 950 and 1050.

My question is in general how this should be connected to the Arduino.

  • \$\begingroup\$ Touch sensor specs? \$\endgroup\$ Jan 12, 2020 at 10:30
  • 1
    \$\begingroup\$ 9 V into an Arduino ---> Unhappy ending. \$\endgroup\$
    – Transistor
    Jan 12, 2020 at 10:42
  • \$\begingroup\$ @Transistor That's why my question says - generally. Please don't look at the specs. \$\endgroup\$ Jan 12, 2020 at 10:56
  • \$\begingroup\$ I'm voting to close this question as off-topic because of "don't look at the specs"! \$\endgroup\$ Jan 12, 2020 at 11:00

1 Answer 1


Firstly, be cautious not to connect the two touch terminals together, it may damage the transistor.

The circuit can be manipulated in various ways to sense for a finger touch at the touch terminal. One of the ways can be to take a wire from the collector of the transistor and give it to the Arduino(make sure to use a lower voltage battery). When the transistor is off(no touch), the voltage at collector terminal should be at a higher voltage level and when transistor is on(touched), the voltage should be at a lower voltage level.

You can check for the typical values that occur at some of the points in the circuit using a multimeter and decide how you can use these points to give input to the microcontroller.


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