A new method for treating electron tubes when used as superregenerative detectors: Part III. Experimental investigation of superregenerative circuits

This is the third of a series of papers dealing with a comprehensive study of superregenerative detection. In the first paper1 the analysis under no-signal condition was given. In the second paper2 the analysis under signal condition was presented. In the present paper, an experimental investigation on superregenerative receiving circuits is carried out to clarify most of the phenomenon involved in these circuits, among which are: the selectivity, the sensitivity, the optimum quench frequency, and the most important phenomena, namely, the synchronization with the signal voltage at the signal frequency ω1/2π and the semisynchronization or the synchronization with one of the equivalent side bands (that is, the synchronization at a frequency equal to (ω1 ± np)/2π', p/2π = quench frequency). In this way, the operating mechanism of superregenerative detectors is clearly explained. For proper reception, free oscillations are generally suppressed. The experimental results are in good agreement with the theoretical predictions given in the preceding papers.1, 2