On the Amplification of Ultra Short Waves by Thermionic Tube

Abstract

If we try to amplify ultra short waves such as 50 meters or less by a vacuum tube amplifier, the inter-electrode capacity of the said vacuum tube will have important effect and the tube get a tendency toward oscillation accompanied by a diminution of the amplification per stage. So that untill recently, direct H.F. amplification of such ultra short waves deemed impossible or impracticable. There exists only few amplifying method of such short waves, such as regenerative systems and various derivatives of them.
The author is engaging on the research of vacuum tube high frequency amplifier especially of a tuned type for many years and devised the method of preventing inter-electrode capacity coupling, which is employed extensively in the broadcast receiving apparatus since then. Now. I improve and as well as to expand my earlier idea. The improved form proved superior than the simple so called neutrodyne system in the 100-300 meter band and much more effective in the ultra short wave region. The following is the first report of the same.