The Model 202A Low Frequency Function Generator is a compact, convenient, and versatile source of transient-free test voltages between 1200 and . 008 cycles per second. It is useful for any general purpose low frequency testing application and is particularly valuable in the testing of servo systems, geophysical equipment, vibration and stability characteristics of mechanical systems, electro-medical equipment, and for the electrical simulation of mechanical phenomena. Three types of output waveform are available; sine, square and triangular. Also, a sync output pulse is available for external use. The Model 202A Low Frequency Function Generator contains a type of relaxation oscillator that is particularly advantageous for the generation of very low frequencies. Both a triangular and a squarewave voltage function of time are inherent in the oscillating system. Also, a sinewave function is produced by synthesis from the triangular wave. Output amplitude and distortion are virtually independent of the frequency of operation. This type of oscillating system in inherently a constant amplitude device so that no A. V. C. system, with associated delay in stabilization after frequency changes, is required. The frequency range from . 008 to 1200 cycles per second is covered in 5 bands. The frequency dial is linear. The output system is a direct-coupled amplifier system designed for either single ended or balanced output. It has good stability with respect to direct current in the output and very low hum level. Both the FUNCTION selectro switch and the AMPLITUDE control are so arranged that the characteristics of the amplifier are independent of their position. The internal impedance of the output amplifier is approximately 40 ohms, and the unit is rated to deliver at least 30 volts peak-to-peak to a 4000 ohm load, A negative peak sync pulse of 10 volts into a 2500 ohm load is also provided. It has a duration of less than 5 microseconds and occurs at the crest of the sinewave and at corresponding positions with the other functions.