I'll admit that I havent played with the TFD but would agree that the
resistive termination would introduce a 3dB power loss. One has to ask
though whether that will be a problem at 80m given band noise etc.

To tell you the truth if I was trying for a 3.5, 4.5 and 7Mhz antenna
I'd probably use just two (crossed) dipoles and figure a way to
mechanically tune between the lower frequencies. Even lumped C comes to
mind.

Only HF loop I ever played with was a 40m NVIS..

Cheers Bob VK2YQA

C. J. Clegg wrote:
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Wouldn't the terminated folded dipole be too lossy at the lowest
frequencies of interest?

Have any of you tried anything like that, and how did it work?