Classic Electronic Restoration, Vacuum Tube Audio, Technical History, Photography

Originally posted in November, 2023 I have recently begun to restore several pieces of Hewlett Packard 70000 Series MMS (Modular Measurement System) equipment. The basic component of the system is a power and/or display frame which can house various test equipment modules. This post documents my restoration of the HP 70001A Power Supply. The Hewlett…

Originally posted in November 2020 RIFA Safety Capacitor Failures have been documented by many of us who restore and maintain vintage electronics equipment. One very spectacular failure was caught live here: courtesy Dave Jones of the EEVBLOG. These capacitors were widely used in test equipment manufactured during the late 1980โs through the 1990โs. The consensus is…

Originally posted in November, 2023 This post documents my investigation of Sprague 672D Electrolytic capacitor failures in HP 70000 MMS test equipment. Background Introduced in 1986, The HP 70000 Modular Measurement Sysem (MMS) is a highly configurable test equipment system comprising spectrum analyzers, DVM, power meter, oscilloscope, signal generators, phase analyzer and more. I have…

Originally posted in June, 2021 Introduced in 1966, the Tektronix 106 Square Wave Generator is a signal generator which can produce fast rise (<1nS @50 ohm loads positive or negative going) or high amplitude (120 Volts, high impedance load) square waves from 10Hz to 1MHz. It is used for oscilloscope calibration, risetime testing and for…

This was originally posted in December, 2017 Tektronix 556 Dual Beam Oscilloscope Testing: Vertical Bandwidth I have been doing some basic testing of my Tektronix 556 Dual Beam Oscilloscope, and I have documented some parts of this process. I have also captured images of the traces, which I will share here. Test Setup: Tektronix 556,…