Yes, you can use Didger to digitize contour lines. If you have a paper map, you can either digitize them using a digitizing tablet or you can scan the map and import it into Didger to digitize on-screen.
After the paper map or image is calibrated, draw polylines to digitize the contours by clicking Draw | Polyline. When you digitize the contours, enter the contour value as the Primary ID for the polyline.
Didger also has the ability to automatically digitize lines from an image (Image | Vectorize Image), so you don't have to manually digitize the contours.
For more information, see here:
Updated August 16, 2018