TSP #337 - Frequency Counters Can Measure DC Voltage! HP 5245L Voltmeter Plugin Theory & Experiments

In this episode Shahriar explores the capability of some frequency counters to measure DC voltage. While this may seem non-intuitive initially, the video shows how the architecture of the HP 5245L Nixie tube frequency counter can be used to realize an integrating ADC. A particular plug-in module, the 5265A, leverages the Start/Stop counter control to implement an ADC and display the equivalent DC voltage at the plug-in input. The theory of operation as well as the teardown of the plug-in in shown. The plug-in module unit is zeroed & calibrated initially and then using a Fluke 5720A the performance of the entire system is evaluated. Despite being in storage for decades, the unit is incredibly accurate and precise. Please consider supporting The Signal Path: https://www.TheSignalPath.com/Donate   / thesignalpath   Other links: https://www.TheSignalPath.com   / thesignalpath