Hey! I'm the creator of the RadioInstigator. Turns out, after reviewing the interference from a GPIO pin, is actually very low (about 5% non-target frequency).

Hey! I'm the creator of the RadioInstigator. Turns out, after reviewing the interference from a GPIO pin, is actually very low (about 5% non-target frequency). I do understand I still have to deal with a comb filter output, but is minuscule from my inspections. Im working on building a programmable filter network with independent low and high bandpass filters. But nothing available for the amateur market is sufficient. There's some stuff for the Ka and Ku bands (high microwave bands 12GHz-40GHz) but nothing for 50MHz-1200MHz. Nobody except for SigInt really cares about such a broad set of frequencies.