All digital inelastic electron tunneling spectrometer utilizing the IEEE-488 instrument bus and an IBM PC-XT controller

An easily assembled computer-controlled tunneling spectrometer is described. Spectral acquisition time is user selectable over a wide range. Low-resolution spectra may be taken rapidly (about 30s/scan) or very slow scans with long time exponential averaging may be chosen. Data are obtained using a two-phase lock-in in magnitude mode so that no phasing of the lock-in amplifier is required. The advantages of this system are discussed and some representative data presented.