Yamaha Portatone PS-35/PS-55 Owner's Guide By Books / Paperback Art & Performing Arts › Music Publisher: Yamaha, Price $25.04 Free Shipping Send to a friend Used - Very Good Very Good condition. No date stated, ca. 1980s. (Keyboard manual, Yamaha) $25.04 1 in Stock at Warehouse Quantity Add Free Shipping to continental U.S. OR $1.00 per item discount if shipped to store.