Abstract: An attenuation measuring system includes a transmitter for generating and transmitting a signal from a first position to a second position, and a receiver adapted to receive the signal at the second position. One of the transmitter and the receiver includes a simple log converter circuit which permits the conversion of an analog signal to a digital signal, so that a time uniform train of pulses is developed, the pulses decreasing in amplitude by equal decibel values. The receiver includes a counter which is counted down from a preset value. The count of the counter is a direct measurement of the loss through a coupling medium between the transmitter and the receiver. The analog-to-digital conversion can be accomplished in either the transmitter or the receiver. When embodied in the receiver, the attenuation meter also can function as an optical power meter.

Abstract: A fiber optic attenuation measuring system includesa transmitter for generating and transmitting a reference signal from a first end of fiber optic cable, and a receiver positioned to receive the signal from a second end of the cable. The receiver compares the transmitted signal with a reference signal to determine attenuation through the cable under test. In the preferred embodiment of the invention, the transmitter and receiver are independent units, which may be positioned separately with respect to one another, and the receiver is constructed to enable it to reproduce the reference signal through the use of a timing pulse transmitted with the test signal from the transmitter. In the alternative, a reference cable may link the transmitter and receiver for comparison with the test transmission.