Re: Why not a resonant loop?
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Yes, the frequencies of our targets may be known.? For loops my interests range from the Schumann Resonance around 7 Hz plus harmonics to roughly 2 to 4 MHz.? Tuned loops have an extremely high-Q.? For example, while using my 1-meter diameter tuned loop for transmit on 40-meters (7 MHz), my 2:1 SWR bandwidth is only some 6 to 8 kHz wide.? Beyond that on receive, I can easily detect its rapid response falloff. ??
Most of us are not after a single frequency as mentioned with the NDB band.? Even with AM BCB "DX'ing", a tuned loop would yield single-station tuning.? The loop would have to be re-resonated every 10 kHz (the AM BCB frequency spacing in the US).??
Dave - W?LEV?
Greetings.? I am a frequent "lurker" and very infrequent "poster" to this forum, my interest is primarily MW.? I usually use a 1m diameter resonant loop and am puzzled as to why resonant loops seem to be out of favor with most of the group members.? The resonant peak provides both "free", noiseless gain to the signal of interest while also rejecting signals at frequencies other than resonance, eliminating the need for high second- and third-order intercept performance.? Granted the broadband loops that are much discussed on the forum can acquire broad swaths of the RF spectrum essentially simultaneously, is this a significant advantage given the fact that the frequency of the signal of interest is known?
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Would someone please discuss the advantages of the broadband loop over a resonant one, have I missed something??
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Thanks
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JohnT
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