Seed and coarsely chop peppers. Peel and cut apples, pears and onion into 1-in. pieces. Pulse in batches in a food processor until finely chopped. Transfer to a large bowl; sprinkle with salt and toss. Let stand 6 hours. Rinse and drain well; blot dry with paper towels., In a Dutch oven, combine drained pepper mixture, vinegar, sugars and fennel seed; bring to a boil. Reduce heat; simmer, uncovered, 40-45 minutes or until slightly thickened., Carefully ladle hot mixture into 8 hot half-pint jars, leaving 1/2-in. headspace. Remove air bubbles and adjust headspace, if necessary, by adding hot mixture. Wipe rims. Center lids on jars; screw on bands until fingertip tight., Place jars into canner with simmering water, ensuring that they are completely covered with water. Bring to a boil; process for 20 minutes. Remove jars and cool.