Thread: Vincent antenna
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Old December 17th 07, 04:12 PM posted to rec.radio.amateur.antenna
Cecil Moore[_2_] Cecil Moore[_2_] is offline
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First recorded activity by RadioBanter: Mar 2007
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Richard Clark wrote:
Are you still ignorant of which of two phases?


I have spelled out the desired phases three times now.
This will be the forth time.

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

The phase shift we are looking for is between Vfor1
and Vfor2. I might as well perform the calculations
for you since you seen to be incapable of doing so.

If we assume a reference of 100 volts at zero degrees
incident upon the open end of the stub, then back at
the impedance discontinuity:

Vfor2 = 100 volts at -10 deg.
Vfor1 = 143.33 volts at -46.6 deg

The phase shift between Vfor1 and Vfor2 is 36.6 degrees
just as it has to be for a 90 degree phase shift to
occur end to end in the above 1/4WL stub.

Vref2 = 100 volts at 10 deg
Vref1 = 143.33 volts at 46.6 deg
--
73, Cecil http://www.w5dxp.com