无变截面变幅杆
一种未经过专门设计以产生增益的变幅杆。在实际应用中，由于螺柱、槽或用于改善均匀性的微小改动（例如凸台和凹槽），无变截面变幅杆的增益通常与 1.0 略有差异。
无变截面变幅杆的侧面通常与螺柱轴线平行。所有棱柱形变幅杆都是无变截面变幅杆。其他典型的无变截面变幅杆包括块形变幅杆，以及工作面无凹腔的开槽圆柱形变幅杆。
参见变截面变幅杆。
Unshaped horn
A horn that has not been specifically designed to have gain. In actual practice, unshaped horns usually have a gain that differs somewhat from 1.0 due to the stud, slots, or small modifications that are used to improve uniformity (e.g., risers and flutes).
Unshaped horns generally have sides that are parallel to the stud axis. All prismatic horns are unshaped. Other horns that are typically unshaped include block horns and slotted cylindrical horns that don't have a face cavity.
See shaped horn.