This experiment follows a previous measurement of an 80 foot length of 9” spaced AWG #28 wire, fixtured using 1:3.8 and 3.8:1 lumped flux-coupled transformers which have been calibrated in a reference impedance of 754 ohms at the line connection plane as depicted in Figure 1.
This experiment is different from the previous one because one of the line conductors has been cut in the middle of the 80’ span and the ends allowed to gradually slope away from the supports so that several feet near the tips could lie on wet sod. Previous measurement of Loop-on-Earth antennasi using similar sod showed that this arrangement can be expected to be a reasonably good broad band absorber of energy conducted by the line.
Beginning at a point 16’ from each end, one line conductor was gently sloped downward and laid on wet grass as shown in the block diagram in Figure 2. This left only 48’ of the other line continuing between DUT measurement planes.
This change in configuration converted the central portion of the previous balanced transmission line into a single conductor transmission line. Figure 2 shows this new configuration and a schematic representation of it.
For this measurement calibration was performed with an open, short and 754 ohm resistive load at the balanced line connection points.
