Hello, Recently needed a DC Injection Bias T, and cheapest offer was from MFJ, around $25, which is way too much as I believe for an inductor. I decided to do one by myself, since I have all the hardware needed. Unfortunately, I found no practical schematics online. Wikipedia article gives some formulas, in which I'm not so strong unfortunately. I'm planning to build Bias T using 4 pieces of 6800pf, 3kVAR rated capacitors in parralel, and ferrite core wound inductor with 200uh of inductance, the core is relatively large, there are only 6 windings on it, and they are quite separated from each other, to reduce cross-capacitance. Will this work in 1.8-30mhz range? btw, I also have spectrum analyzer with sweep generator, so I can take a sweep of the band to see if there's any attenuation, but how to check for RF leakage at DC supply point?