Abstract: These applications usually require a few watts of cooling powet at 80 K and high reliability and low cost.We have previously designed and tested a U-shaped pulse tube refrigerator driven by a modified air conditioning compressor.In this paper we report a coaxial pulse tube refrigerator which is more convenient to use.A minimum temperature of 38.4 K and more than 6 W of cooling power at 80 K have been achieved with about 620 W of compressor power input.Besides,the startup process is simple,cooling down tine short, efficiency high.