In a large mixing bowl, combine the lemon juice and water. Set aside until ready to use.
Peel, core, and dice the fruit into 1/2-inch cubes, with the exception of the strawberries. Slice the strawberries 1/8-inch thick. Place the fruit into the lemon water and allow to soak for up to 2 minutes. Remove and drain thoroughly.
Lay 1 (14-by-14-inch) plastic dehydrator sheet on 1 of the air-conditioning filters. Place the fruit on the plastic dehydrator sheet and cover with another plastic sheet. Repeat this process with remaining plastic sheets and 2 more filters, stacking on top of the first one. Top these with the remaining 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 2 bungee cords. Stand the fan upright, plug in and set to high. Dry for 42 to 48 hours. When dry, the fruit should be pliable but not sticky. You should not be able to squeeze moisture from the fruit. If using a commercial dehydrator, follow the manufacturer's directions.
Remove the fruit from filters and store in an airtight container in a cool, dry place.