[TowerTalk] ++ High SWR and Modern Transceivers

[Tom Rauch]

> Consider the case of a conventional T network matching an 
> impedance lower than the lowest obtainable surge impedance of 
> the network. With 220pF capacitors, that would be about 3000 
> ohms on 160 (1500 ohms on 80 meters, 750 ohms on 40 meters, 
> and so on).

Woops, the results are correct but I described the impedance 
wrong.

In this case the surge impedance of the network would be the 
geometric mean of the input and output impedance. Phase shift 
would be 90-degrees, and the network would appear as the 
electrical equiv of a transmission line 90 degrees long with an 
impedance of the square root of 50*3000, or 387 ohms in the 160 
meter example I posted.

In this example, all components are adjusted to have the same 
reactance. This is the lowest possible operating Q matching 
system between a source and load resistance.
73, Tom W8JI
W8JI@contesting.com 

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