I had the same problem with a weather sat; here is how I solved it: 1. Design a ship, with weather core, and save it. 2. Use a text editor like Notepad to open the saved .craft file - something like \Kerbal Space Program\saves\BuzzKaldrin\Ships\VAB\weathersat.craft 3. Search for "part = WeatherCore_" - this will get you to the correct PART block. (For a navigation sat, use NavigationCore_; for research, use ResearchCore_.) 4. Search for "frequencyModulation =" - this will get you to the current frequency setting. Change it to "frequencyModulation = 0.5". Save the file. 5. Reload your ship in KSP.
