Hi,
I'd like to build a row of 8 resistance touch sensors.
I am not that familiar with electronics so I started with a tutorial of how touch sensors work: **broken link removed**
This example worked very well and so I wanted to continue to a design with an IC housing 8 darlington circuits. I used the ULN2803A and (with 7 darlington circuits) the ULN2001A.
I connected the Pin1 (Input or Base) with two open cables (my touch sensor) and the other side to Vcc. Pin 18 (Output or Collector) I connected to an LED which was connected to Vcc, too. Pin9 was set to GND. However the whole thing does not work. I am not quite sure why but I think that the connected parts are right but the dimension of the resistors (R1 between my open cables and Vcc and R2 between the LED and Vcc) is not correct. I was trying to read the datasheet of the ICs but was not able to figure out what data is relevant to me. Can someone help?
Thanks
Sas