HP 00424-90026 1969 Model 424A Crystal Detectors Operating Note Manual.

HP 424A Crystal Detectors Operating Note 00424-90023 July 1967

HP 01914-7 1967 Model 424A Crystal Detectors Operating Note Manual.

HP 16008-99000 1974 Model 16008A Resistivity Cell Operating Note Manual.

HP 00422-90006 1969 Model 422A Crystal Detectors Operating Note Manual.

HP 00212-2 Model 885A Waveguide Phase Shifter Operating Note Manual.

HP 15117-90000 1969 Model 15117A Sound Level Calibrator Operating Note Manual.

HP 00422-90009 1979 Model 422A Crystal Detector Operating & Service Manual.