Accession Number : AD0663708

Title :   LOW FREQUENCY SUB-AUDIO TRIPLEXER.

Descriptive Note : Technical rept.,

Corporate Author : TEXAS UNIV AUSTIN DEFENSE RESEARCH LAB

Personal Author(s) : Hamblin,Herbert A.

Report Date : 02 JAN 1968

Pagination or Media Count : 59

Abstract : A low frequency sub-audio triplexer was designed and built for use with a thermal writing paper oscillograph machine. The purpose of the triplexer is to enable one channel of a recording system to record three different input signals; this is accomplished by electronically switching the output circuit to each of three input circuits, one at a time. Each input base line can be controlled as can the time duration during which a given input is sampled. Also, a coding signal is provided for positive identification of each signal. The one output circuit and the three input circuits are balanced with respect to ground; with both sides floating, the input signals can be triplexed. The frequency response of this circuit is from dc to 3 dB down at 360 kHz with better than 60 dB of isolation (measured at 15 Hz) between the various input circuits. Also, a 5 M ohms ladder attenuator is provided on each input so that large signals may be triplexed. The circuit input impedance is 5 M ohms and the output impedance is about 100 ohms. The dynamic range is approximately 92 dB with the maximum allowable input signal equal to 11.5 V peak-to-peak. (Author)

Descriptors :   (*RECORDING SYSTEMS, *MULTIPLEXING), EXTREMELY LOW FREQUENCY, OSCILLOGRAPHS, RECORDING PAPER, COUNTING METHODS, GATES(CIRCUITS), LOGIC CIRCUITS, SWITCHING CIRCUITS

Subject Categories : Recording and Playback Devices

Distribution Statement : APPROVED FOR PUBLIC RELEASE