Need help with sketch insert

[Irachkom]

Greetings!
I want to add this sketch to my image, but I can't get any method to make it "lines only", I don't need background, need just image, so I could insert this into any image.
Anyone knows any method, how is it possible to remove background, or make it transparent?

 

[chrisdesign]

I used curves and desaturation a few times.

 

[Irachkom]

I used curves and desaturation a few times.

View attachment 93345

Awesome! Many thanks! Will try to add this =)