Before revision: History alt=Schematic diagram shows six vacuum tubes|A TRF receiver using a grid leak detector (V1) Early applications of triode tubes (Audions) as detectors usually did not include a resistor in the grid circuit.CDR S. S. Robison, Manual of Wireless Telegraphy for the use of Naval Electricians, Annapolis, MD: United States Naval Institute, 1911, p .125 J .
After revision: History alt=Schematic diagram shows six vacuum tubes|A TRF receiver using a grid leak detector (V1) Early appplications of triode tubes (Audions) as detectors usually did not include a resistor in the grid circuit.CDR S. S. Robison, Manual of Wireless Telegraphy for the use of Naval Electricians, Annapolis, MD: United States Naval Institute, 1911, p .125 , 132J .