Automatic Tuning, Simplified Circuits, and Design Practice

  title={Automatic Tuning, Simplified Circuits, and Design Practice},
  author={D.E. Foster and S.W. Seeley},
  journal={Proceedings of the Institute of Radio Engineers},
  • D. FosterS.W. Seeley
  • Published 1 March 1937
  • Engineering
  • Proceedings of the Institute of Radio Engineers
The principles underlying automatic frequency control of the oscillator in superheterodyne receivers have been outlined in previous papers given before the Institute of Radio Engineers. This paper deals with simplification and improvements in operation of frequency control circuits and their application to automatic (electronic) tuning control. A new type of "discriminator" which differentiates between mis-tuned signals on the high-frequency side of resonance and those on the low-frequency side… 

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