Power Venturi Tube, Double Throat, AN5807-1, Type B-4A Short Stirling Oil Pressure

Oil Pressure

and post WWII

otherwise each page is clean

According to the Graphic Survey of Radio And Radar Equipment Used By The Army Air Forces dated July 1945:

This edition contains a misprint of pages 201-239 covering about 10 pages of the Scintilla chapter and most of the Friez test/recording instruments chapter

Power Venturi Tube, Double Throat, AN5807-1, Type B-4A Short Stirling Oil PressureThis is a nice specimen of the Double Throat Power Venturi Tube used across US military aircraft of the US Army Air Corps Force and US Navy before, during, and post WWII. Made by Sperry, part number 640600. Power venturi tubes provide a source of vacuum for the operation of air driven instruments such as directional gyros, gyro horizons, and turn and bank indicators. The venturi is a tube shaped like a double "V" and has a small opening, called a