Experimental research on multiple stages EMP protection measure for HF transmitter

In this paper experimental research was made to investigate the effect of multiple stages EMP (electromagnetic pulse) protection measure based on SG (spark gap) and GDT (gas discharge tube). The result showed that the advantages of measure were large current conduction capability and simple structure. In the case of incident pulse amplitude equal to 40kV, the residual pulse amplitude was less than 1kV. The drawback of the measure was that the breakdown voltage of spark gap was unstable and would not achieve good repeatability.