WW2Y and K2WI decided to compete with W2GD on topband. W2GD and his crew would setup at the end of Sandy Hook NJ. They had full wave loops, and Beverages, etc for 160 meters on a spit of land stuck out on the Atlantic Ocean.
These are seasoned CW contest and DXpedition operators. They had FT1000s and Drake 4Cs with N9EWO mods. >From a residential lot in Princeton WW2Y and K2WI started by installing an inverted L in the trees for 160 meter. That became four inverted Ls in a trapezoid aimed to the northeast fed with transmission line transformers to correctly phase the elements for extra gain. When they built and installed the beverages they noticed they had just as much noise as the other antennas if not more. I modeled the Beverage and discovered it was a very high loss antenna. The soil was the lossy element and if you tried to reduce the loss by tuning the termination and matching networks you compromised the front to back ratios and lost directionality. The performance of the Beverage was dependent on soil characteristics and difficult to model and variable to to due to rain etc. We put an oscillator in the park behind Princeton shopping center. Before a contest the termination and matching was tweaked to null the oscillator in the park while favoring European stations. The Beverage is a lossy antenna with the least loss in the desired direction when correctly terminated and matched for the soil conditions. Even with the lossy antenna the AM broadcast band still interfered with the receivers. So we added traps both lumped element and transmission line coax. They were able to protect the receivers, but the noise figure of all that insertion loss plus antenna loss was now compromising the sensitivity even for 160 meters reception. An amplifier using a 2N3866 was designed for low noise at 1.8MHz and placed just after the Beverage, but because it was 5 Watt device it could be biased up to handle the AM broadcast signal without losing linearity. Its low noise and high gain fed the lossy traps and filters that protected the receivers while getting the system noise figure and sensitivity back were it was required. They also found that they could now insert a trap after the 2n3866 amp at the transmitter frequency and listen while they were transmitting a few KHz away. This search Drake 4C N9EWO receiver was used by a second operator to tune around the band looking for stations not yet worked. Then handing the main transceiver operator the frequency it the station was calling CQ. Or if the station was actually calling them switch the audio to the main stations headphones so he could work him. BCNU DE N2LO~>
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