Place the salmon in the freezer for 45 minutes to 1 hour.
Place the soy sauce, molasses, lemon juice, black pepper and liquid smoke into a large ziptop bag, seal and shake to combine. Remove the salmon from the freezer and cut into thin strips. Add the salmon strips to the bag with the marinade, reseal and allow to marinate for 1 1/2 to 3 hours.
Drain the strips in a colander and pat dry on paper towels. Evenly distribute the strips of salmon onto 2 of the air filters and then stacking the filters on top of one another. Top these with one empty filter. Next, lay the box fan on its side and lay the filters on top of it. Strap the filters to the fan with two bungee cords. Stand the fan upright, plug in and set to medium. Allow the meat dry for 12-18 hours. If using a commercial dehydrator, follow the manufacturers directions.
Once dry, store in a cool dry place, in an airtight container for 2 to 3 months.