Voltage measurements are fairly straightforward most of the time. Simply grab any old cheap multimeter, hook the probes and read the answer. However, if you have to measure a very small voltage, the problem becomes more complicated. [Jaromir-Sukuba] A nanovoltmeter has been specially designed to deal with this difficult case.
The nanovoltmeter sounds exactly like this: a voltmeter that is sensitive and stable enough to measure and report voltage on a scale of nanovolts. Having a tool that can do this reliably can be very useful when it comes to measuring very small resistances or when working with ever-slightly differential voltages.
The design of this type of device is quite involved in reducing the source of noise and instability. Analog-to-digital converters must be of high quality and must be powered by their own supply to avoid additional noise. There are low-noise amplifiers and all sorts of special subsystems needed to get the job done. There is also a 3D-printed cover to prevent airflow over a voltage reference to reduce noise from thermal variants.
Still, [Jaromir-Sukuba] It does a great job of exploring what is needed to make a nanovoltmeter and explains it well to new viewers in the case of such precise measurements. As a result, the instrument was able to measure less than 25 nanovolts with noise peak-to-peak. This is a great achievement and a great resource for those who are interested in learning how to do it.
We’ve seen other clever measuring devices before. Did you know that you probably already have a usable nano-emitter? Ha shah ah!
[Thanks to David Gustafik for the tip!]