Following the world tendency in the application of microcomputers in measuring instrumentation, standard personal computer, compatible with IBM PC/XT, was employed in the isotope gauges developed lately in the Institute. They are: beta backscatter coating thickness guage, X-ray fluorescence multilayer coating thickness gauge with X-ray tube as radiation source, and automatic airborne dust pollution gauge. A simple interface containing: address decoder, programmable pulse counter, some buffers and latches was sufficient to connect the computer to the measuring head of the gauges. Thanks to the possibility of programming in higher level language (turbo Pascal), the gauges were developed in much shorter time than required for classical electronics. The experience gained during development of the gauges shows, that even in case of a simple instrument such as the beta backscatter coating thickness gauge, it is more economical to employ ready-made personal computer than to elaborate specific electronics for it, unless the gauge is produced in large numbers. The use of personal computer is particularly advantageous, when processing of the signal or control of the measuring cycle is more sophisticated, as in the case of the two other gauges.
Block diagrams of the gauges and their interfaces are presented in the paper. In case of trie airborne dust pollution gauge, flow chart of the computer program is also given.