Query..
"Cecil Moore" wrote
Reg Edwards wrote:
A terminated rhombic is only 50 percent (or even less) efficient.
But it's 50% in the bad direction, not the good direction. :-)
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In the most simplistic of terms, a rhombic consists of four
1/2-wavelength wires plus a lossy resistor which gets hot.
If the four 1/2-wavelength wires are rearranged to form a dipole, plus
a reflector, plus two directors, we have only one good direction in
which 100% of the power is radiated. Nothing gets hot.
Common sense prevails. No need to refer to Eznec. Even a drunken
old-wife would know which arrangement to choose, if only because it
saves the cost and fitting of a high power, non-reactive resistor.
;o)
But no doubt US Army Field Manuals still call upon rhombics.
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Reg.
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