A temperature compensation apparatus for a cavity filter including a plunger barrel, a compensation barrel having a first coefficient of thermal expansion, wherein the compensation barrel is housed with the plunger barrel, a tuning rod housed primarily within the compensation barrel, the tuning rod having a second coefficient of thermal expansion, and wherein the compensation barrel is physically in contact with the plunger barrel and the tuning rod for allowing a direct transfer of heat between the compensation barrel, the tuning rod, and the plunger barrel.