The Circuit Designer's Companion - diagramas.diagram...

Grounding and wiring 39of Z o . Thus a shorted line will have a virtually zero impedance λ/2 away from the short,which property can be used to create a distributed tuned circuit.Lossy linesThe preceding discussion assumes zero-loss lines, which in practice are unrealisable.For short line lengths the losses are usually insignificant − see Table 1.7 for typical coaxlosses. Note that these are quoted for the matched condition. If the line is operated withstanding waves, the loss is greater than if it is matched because increased voltages andcurrents are present and the average heat loss is greater for the same power output. Theeffect of attenuation in long lines is to cause an improvement in s.w.r. towards thegenerator, since the effect of a mismatch is attenuated in both directions. In the limit, along cable can make a very good power attenuator!