Pulse Current Injection (PCI) is an important means of studying the High-altitude Electromagnetic Pulse (HEMP) effects on electronic equipment. This paper designs a shortwave antenna port contact pulse current injection experimental platform, studies the effects of two different working states (receiving and transmitting) of shortwave equipment, as well as the impact of three different working frequencies (low, medium, and high) on the injected current. It also explores the performance differences of antenna port protectors in both stand-alone and online states, providing a reliable basis for subsequent performance tests of shortwave antenna port resistance to electromagnetic pulse interference.