Fill deep fryer halfway with oil and heat to 350°F.
In a shallow dish, whisk together egg and club soda. In another shallow dish or medium bowl, combine flour and baking powder.
Dip pickle slices in egg mixture and then dredge in flour mixture.
For the ranch dipping sauce, in a small bowl, combine ranch dressing and salsa, mixing well. Cover and refrigerate until ready to serve or for up to 1 day.
Fry pickles in batches, turning once, for 2 to 2½ minutes or until golden. Use a metal slotted spoon to transfer to paper towels.