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Cecil, W5DXP wrote:
"If a 180 degree reversal in the direction of flow of current ia not a 180 degree reversal in reality, exactly what is it?" From the 1937 second edition of Terman`s "Radio Engineering" page 70: "In the case of both open- and short-circuited receivers (transmission line loads) the voltage and current are substantially 90-degrees out of phase at all places along the line except in the vicinity of the quarter-wave-length points where the phase angle rapidly shifts from nearly 90-degrees on one side of unity power factor to nearly 90-degrees on the other side of unity power factor. The voltages on opposite sides of a voltage minimum are therefore substantially 180-degrees out of phase, as are also the currents on opposite sides of a current minimum. In order to show this change of phase, the voltage and current distributions in circuits with distributed constants are frequently drawn as shown in Fig. 34---." It helps to have Terman`s Figs. 33 and 34 in front of you to be persuaded of the abrupt phase transistions. Terman can be accepted on faith and his truth eventually sinks in. Best regards, Richard Harrison, KB5WZI |
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