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A generator of the harmonic signal is described for frequencies in the acoustic region with the reference stabilized amplitude, linear frequency scale and total harmonic distortion below 2 10. The signal is produced as the solution of the corresponding differential equation where the constant amplitude is maintained by periodic control of the first derivative value x(t) at the moments when x(t) crosses zero and has a positive slope. [ABSTRACT FROM AUTHOR]

A new variable frequency oscillatory system is described. For certain system conditions the circuit produces a sine wave oscillation whose frequency is varied over a wide range from a very low to a high value simply by varying the gain of an amplifier rather than by changing the circuit time constant and accordingly no ganged condensers are used. Another important feature of the circuit is that the generation of a very low frequency oscillation is possible without incorporating a large value of the RC product. The oscillator utilizes air amplitude stabilizer operating on the controlled linear resistance of the initial region of the characteristic of a junction FET. The frequency relation is derived and the results are compared with experiment and found in agreement. [ABSTRACT FROM AUTHOR]

While generating very low frequency sinusoidal voltage, using operational amplifiers, one experiences difficulties in stabilizing the amplitude and every endeavour has been made to get a satisfactory solution. The paper describes one method by which stable oscillation can be obtained to a frequency as low as 0.01 c/s. The oscillator consists of two integrators and one sign changer interconnected in the form of a closed loop so as to solve a second-order differential equation. The amplitude is stabilized with the help of an extra stabilizing loop which consists of a squaring network. A brief analysis of the oscillator has been carried out and the precautions that have to be taken for improving the oscillator performance are discussed. [ABSTRACT FROM AUTHOR]

Investigates the performance of the Darlington composite transistor oscillator. Research on the Darlington composite transistors; Analysis on the schematic diagram of the Darlington transistor oscillator; Assessment on the frequency oscillation of single stage transistor oscillator.

Discusses a frequency modulated phono-oscillator which can reduce records through a frequency modulation receiver without wired connections in the article 'FM 'Wireless' Record Player uses Capacity Phono-Pickup,' by Arthur Trauffer.

Presents an article 'A New Direct Crystal-Controlled Oscillator with Ultra-Short-Wave Frequencies,' by W.P. Mason and I.E. Fair, published in the October 1942 issue of the journal, 'Proceedings of the I.R.E.'