Re: QRP Labs #dummy load at 0dBm #dummy

Tim Glennon

Guys when I was working and did EMI, EMC testing we would put a “T” in the coaxial line to the dummy load and on the “T” we would attach a 1/4 wave open end stub cut to the fundamental frequency, if your careful and use good coax you can notch out the fundamental my over 40 dB. This technique gives a very high “Q” notch filter.
In fact in one case we were able to get a 70 dB notch with having very little effect on the harmonics

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