I've come across some template designs that have tuning dots included for RF matching. Unfortunately they are using a different dielectric than I am.
What are the basic principles of tuning dots (theoretical to purely mathematical would be great), and how do I then change their design to fit my own boards specifications?
NOTE- tuning dots are filled in the end design, this is merely how my importer displays them
Answer
Their purpose is to provide a means of adding variable length stubs for impedance matching. A wire bond can be connected from the bondable gold surface of the microstrip center trace to the pad. The bond wire will have an inductance value based upon bond height/length and wire thickness; the bond pad will have a known capacitance based upon the substrate dielectric and the pad geometry.
A very brief mention of their use can be found here. Additionally, their use is discussed at Microwaves101, where they are called "chicken dots".
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