On 8/12/16 11:53 AM, TexasRF--- via TowerTalk wrote:
And the results are intuitively obvious for even the most casual observer,
right?
The pdf mentions 1/4 and 1/8 wavelength multiples. Can we take it that
random lengths do not work for the concept?
They work, but the math gets more complex. the transmission line
equations have a lot of terms that go to one or zero when you've got an
exact multiple of pi/2. And pi/4 (1/8 wavelength) is often a nice
special case (e.g. sin(pi/4) = cos(pi/4))
It's all hyperbolic sine and cosine (with complex numbers).
It is NOT generally suitable for hand calculation (or even
pencil/paper/calculator).. but you can do it in a Excel spreadsheet, or
use something like Octave, Matlab, Mathematica, etc.
Excel does do complex math, but you have to build the hyperbolic
functions using IMEXP(x) (complex e^x)
imsinh(x) = improduct(0.5,imsub(imexp(x),imexp(improduct(-1,x))))
imcosh(x) = improduct(0.5,imsum( imexp(x),imexp(improduct(-1,x))))
if you're doing a lot of calculations with the same argument x, you can
build some intermediate results that make life easier. exp(-x) =
1/exp(x), for instance. so imdiv(1,imexp(x)) is the same as
imexp(improduct(-1,x))..
73,
Gerald K5GW
In a message dated 8/12/2016 1:41:50 P.M. Central Daylight Time,
steve@karinya.net writes:
http://www.karinya.net/g3txq/wet_ll/tl_formulas.pdf
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