It is often said that pulsars can be used as tools, and this talk will discuss one of the newest ways that this characterization is true. As part of NANOGrav’s timing campaign to detect gravitational waves, we observe some of the brightest and most well-studied pulsars in the galaxy. This, coupled with pulsars’ remarkable stability allows us to use them as calibrator sources, letting us detect and account for imperfections in the telescope’s receiver.

We have applied this method to NANOGrav’s observations with the Arecibo Observatory, resulting in one of the most sensitive sets of polarimetric profiles available. As a product of the Faraday rotation caused by the ionized interstellar medium, we are also able to use this data set to measure the galactic magnetic field parallel to the lines of sight to the brightest of these sources. The sensitivity of this data set also allows us to detect profile “microcomponents”, that is, profile components with intensities less than 100 times fainter than the profile’s peak intensity.