9AAU - 9ZK 1926 St. Louis, MO

This 1926 Christmas card from 9AAU and 9ZK shows father and son.
Father: Dr. Charles L. Klenk, MD is shown on the left. He was not licensed. 
C. W. Klenk was his son Carl W. Klenk.

Carl W. Klenk, W0ZK, ex-W9ZK, 9AAU, 9ZK and 9DS, was a radio engineer for an aircraft manufacturing company in St. Louis, Missouri in 1930 and 1940.
A 1924 issue of Radio Age magazine had an article about his station: "9AAU was well known for his consistent DX work in both receiving and transmitting and he was heard in every district in the United States."
Carl was born November 26, 1907 in St. Louis, Missouri and became a Silent Key in May 1966.

QSL W2BTD Collection
Photo courtesy of W5ODD
From the estate of W5JC
Info courtesy of W5KNE