mvoltin asked:
what program did you use to draft the PCB diagram?
I used a combination of LTSpice and MS Paint. I drew the schematic in LTSpice first, then pressed the PrnScn (PrintScreen) button. I then opened MS Paint, and pressed the Shift & Insert keys together. This dumps the screen image of the LTSpice schematic into Paint. I then used the various utilities in Paint to edit the image (erasing unnecessary LTSpice comments, copy/pasting resistor symbols, changing a resistor into a variable resistor, cropping the image and so on).
An additional virtue of this method is that both LTSpice & MS Paint are free (the latter for Windows users like myself)
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