Mallory Service Encyclopedia 

  Mallory and Mallory / Yaxley Service Guides from 1937 to 1946

The Mallory Radio Service Encyclopedia was published from 1937 to 1946, with the War years of 1942 to 1945 being a hiatus for the duration. A final issue was published in 1946.
"For years it has been the Mallory-Yaxley pledge to retain leadership in furnishing constructive, helpful information, and assistance to the Radio Service Fraternity-and to make that information worthy of its confidence. In this, the first Radio Service Encyclopedia, there is ample evidence of this pledge."

Credits
Thanks to John O for the 6th edition!
 
Mallory Yaxley Service Encyclopedia
1930's 1936 1938 1939
Mallory Yaxley
Service Encyclopedia
Edition 1
Mallory Yaxley
Service Encyclopedia
Edition 2
Mallory Yaxley
Service Encyclopedia
Edition 3
1940s 1941  
 Mallory Radio Service Encyclopedia Edition 4 Suspended during the War years.
1940s 1946 1947
  Mallory Radio Service Encyclopedia Edition 5   Mallory Radio Service Encyclopedia Edition 6  Ceased Publication