VSWR meter

1-18 — elektor january 1980 VSWR meter VSWR meter Fortunately, it is not too difficult to avoid mismatching. Provided you know what you"re doing, that is! If you buy a transmitter ready-built, the output impedance is usually specified. The same is true for transmitting aerials: the op manufacturer will normally specify the impedance. The idea is that you use an aerial with an impedance that matches the output impedance of the transmitter, and that you use connecting cable with the same characteristic impedance. For instance, if the transmitter output is specified as 75 C2 the obvious thing to do is to use 7512 coax cable and a 75 aerial. However, life is not always so simple. Many amateurs not only build their own transmitter; the transmitting aerial, too, is often the result of personal exper- iment. In this case both impedances are unknown, so that optimum energy transfer from transmitter to aerial can only be obtained by experimenting. Why? The simplest possible equivalent ci...