[Elecraft] SWR MYTHOLOGY (was KAT100 and external watt meter question)

[Don Wilhelm]

----- Original Message -----
> ...  Dipoles do not work well on the second harmonic.
> ...

Folks,
It is fair to say that a dipole (fed with coax) does not work (match) well
on the second harmonic, but it is quite true that the antenna itself is a
very efficient radiator - in fact a full wavelength antenna is also known as
'two half waves in phase' and can show up to 3dB of gain in its favorable
direction (single bi-directional lobes broadside to the antenna).

A full wavelength antenna fed in the center does have a very high feedpoint
impedance, but a good quality open wire line or ladderline will handle it
with ease - one can use a tuner that can handle the high impedance or use a
feedline length of something close to an odd multiple of a quarter
wavelength to transform the feedpoint impedance to a lower value where your
tuner can easily match it (don't shoot for an extremely low impedance though
because resistive losses in the tuner often are much higher due to the
increased current when feeding an extremely low impedance - like less than
20 or 25 ohms).

73,
Don W3FPR