To reduce the number of the components of a low noise block converter and the number of metal components of a compact satellite antenna, and to share the components by making the mounting position of an arm metal variable.

An LNB(low noise block converter) 11 is mounted through a holder 3 to one edge side of an arm metal 6. In this state, deviation values L1 and L2 are generated respectively in a horizontal direction and a vertical direction only by the thickness of the holder 3 at the focal position of the LNB 11 and the focal position of a paraboloidal reflecting mirror 1. Countermeasure to this deviation value is attained by changing the mounting position of a support metal 7. That is, the focal position of the LNB 11 can be prevent from being deviated by piercing a screw through-hole for mounting an LNB for receiving a linearly polarized wave at the position corrected by the deviation values L1 and L2 for a screw through-hole for mounting the arm metal at the time of mounting an LNB 2 for receiving a circularly polarized wave thereby making the mounting position of the arm metal 6 variable (adustable).