Once you have decided a trimmer capacitor is a good fit for your application, there are numerous additional decisions to make. In addition to the many dielectric options, trimmer capacitors are also available in numerous package styles, including those designed for PCB mounting, panel mounting, and surface-mount applications. Trimmer capacitors are even available for low-temperature applications in cryogenic systems and manufactured without magnetic materials for use in critical industrial and medical applications such as MRI systems.
There are also many specifications to consider when comparing trimmer capacitor options including capacitance range, the number of turns required to cover the capacitance range, the SRF, the minimum Q, temperature coefficient, tuning torque, DC working voltage, DWV, and size. When looking at these specs and comparing components from different manufacturers, it is important to normalize values for these characteristics as much as possible since manufacturers may use different reference points for measurements.