Kerry Wong writes:
A couple of weeks ago I did a teardown of HP 6181C — a precision DC current source made in the late 70′s and early 80′s. This time around, I am going to show some pictures of an HP 6113A precision DC power supply and do a basic calibration using my Keithley 196 multimeter.
I bought this HP Harrison 6113A DC power supply on eBay a while ago. This series of precision power supplies were made way back in the late 60′s and early 70′s. It consists the following models: 6110A (0-3000V, 0-6mA), 6111A (0-20V, 0-1A), 6112A (0-40V, 0-500mA), 6113A (0-10V, 0-2A), 6116A (0-100V, 0-200mA). Among these five models 6113A has the highest output voltage resolution (100 µV). Even by today’s standard, this specification is still quite impressive and can only be found on some of the most expensive power supplies.