Capacitive Touch Switch

[Lesterwyatt]

I have uploaded a 3 part series of my capacitive touch switch design on youtube. In part 1 i start with the concept on a breadboarded circuit using an LM358 op-amp triggering a 555 timer in monostable. Part 2 i replace the 555 with a pic12 which triggers a relay in toggle and timed mode.
Part 3 I transfer the circuit to PCB using the dry film method and install the completed design.

In Part 2  I show a schematic capture on Altium, However there is an error in the circuit (C4 node should be above R5 of the input to the LM358).

If you can get through part 1, part 2 should be linked from the end of part 1 and likewise for part 3.

Part 1 is bellow.

Thanks Lester

https://youtu.be/wxgRXSTshpA
 

[Lesterwyatt]

Part 2 and 3 bellow:

https://youtu.be/NB3ycKquvTs


https://youtu.be/IEqtF_0HjJ8

[bsfeechannel]

What printer did you use to transfer the negative to the transparency film? The black areas seem really opaque.

P.S.: Kitten math is simple: you + kitchen = food.

[Lesterwyatt]

Hi, i used a Canon LBP 6030 laser printer.