Photo courtesy N6AW
Don Wallace, W6AM (SK) was one of the world's most visible amateurs during most of a ham career that spanned 75 years. As 9ZT, Don was awarded the 1923 Hoover Cup for "the notable efficiency of your radio station and your activity in amateur radio work."
This transmitter used a single Radiotron UV-204 (later replaced by the UV-206, which had a 500-watt plate dissipation and could comfortably be run at 1500 watts input), and operated on 215 meters (1395kHz) and 115 meters (2600kHz). Don's transformer was a burned-out 3KW line transformer, whose 6000-volt tap was used into a 124-jar aluminum and lead rectifier. His rectifier solution was made up of ten gallons of battery water, two pounds of Twenty Mule Team Borax, and a teaspoon of household ammonia.