Re: Proposed fix for Harmonics Issue

Howard Fidel

Thanks for your support. I am a true believer in the KISS principle. I have spent my professional engineering career putting out "fires" with simple elegant solutions and designing new products. Now in my "retirement" years (actually I still work part time, teaching) I have time to get back to a hobby I started in juniorĀ  high school that launched my career in medical electronics. It has been a lot of fun working on the uBitx, and it has exposed me to many engineering issues that I didn't face in the medical area. My plan from the beginning is to use it as a learning experience to launch my next project which will be a SDR transceiver. These harmonics and spur issues have been a distraction but also a great learning experience. It is great to see so many of us working on solutions.


On 8/12/2018 9:02 AM, John KC9OJV wrote:

Your solution seems to be the "holy grail" elegant fix for this problem. Even if the board layout impedes the success of this idea it points to a version 5 modification that could be easily implemented in India. On another note, I don't have a lab grade spectrum analyzer but I do have a RF Explorer analyzer and I loosely coupled it yesterday looking at 40 and 20 meters. The harmonics were present and objectionable. I installed a contester's 6 band switchable bandpass system and the harmonics were sufficiently suppressed. Apparently external filtering is an effective interim solution. Thanks so much for the good thinking on this vexing trouble!


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