Thread: Vincent antenna
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Old December 17th 07, 03:11 PM posted to rec.radio.amateur.antenna
Cecil Moore[_2_] Cecil Moore[_2_] is offline
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Richard Clark wrote:
You still show signs of confusion. Phase shift in what?


I have explained it twice already. Given the following
4-terminal network impedance discontinuity at '+':

---43.4 deg 600 ohm line---+---10 deg 100 ohm line---open
Vfor1--|--Vfor2

What is the phase shift in the forward voltage at the
impedance discontinuity? The forward voltage on each
side of the impedance discontinuity , '+', is not
equal in magnitude or phase.

We know the stub causes a 90 degree phase shift end to
end. Since there is 43.4 deg phase shift in the 600 ohm
line and 10 deg phase shift in the 10 ohm line, guess
what the phase shift in the forward voltage has to be
at the impedance discontinuity?

Also previously explained, if you prefer - in s-parameter
terms: What is the phase shift between a1 and b2 in the
s-parameter equation:

b2 = s21*a1 + s22*a2
--
73, Cecil http://www.w5dxp.com