PDF to DWG Drawing Conversion.

I have a project where I need to redraw pdf copies of two electrical ladder drawings into a .dwg format. The drawings are a total of 19 pages. The original versions were lost years ago and I need to modify them, but do not have the time to redraw them myself. Once the two drawings are recreated in .dwg format, I can perform the updates that are required. To be clear, I only need the pdf copies that I have re-created in .dwg format. Thank You.