Midseries and Midshunt Terminations

Figure 4 shows an unbalanced network extending to infinity in both directions. It is desired to select a finite portion of this network to use as a transmission system. Suppose the portion A-B is selected by cutting the network at 1/2Z₁. This will give the network of Fig. 5a, and the network is said to have mid-series terminations, because it "starts" and "ends" in 1/2Z₁.

Another possibility is to select the finite section C-D (Fig. 5b). This network is said to have mid-shunt terminations. The value 2Z₂ is specified because two such impedances in parallel give the impedance Z₂ of Fig. 4. The infinite network could have been cut into at any point; then fractional termination would have resulted.