>And for how long did 468/f rest resplendent in the books,
>unquestioned, until Joe Common Ham got his mits on antenna modeling
When I was a kid, the ARRL handbook offered 468/f as an approximation
of the length of a dipole @ 1/2 wave height. It was stated rather clearly
that trimming would be required to accomodate site-variables.
Last week, I cut an 80m dipole using 468/f as a starting point. Went up as
an inverted Vee. Took perhaps 10 minutes with a meter to trim off a foot
from each end, precisely as expected. (I always add a foot on 80 & 40,
just to give me room to trim. THAT they didn't put in the handbook!)
Evidence suggests that 468/f is still a workable approximation.
It would seem that Joe Common Ham may suffer from an over-reliance on
model data, or a lack of common sense in applying it.
Perhaps it's the expectation that you can predict unseen environmental
variables with any precision whatever.
Jim Jarvis, N2EA