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Eric Rodgers

The purpose of this project is to find out the amount of loss in frequency and amplitude of an audio signal, if any, results when the audio signal is transmitted through a fiber optic cable at different degrees of bend diameter. I believe that the audio signal will lose frequency and amplitude when transmitted through fiber optic cable with a smaller degree of bend diameter.

The fiber optic transmission system was set up and was run into a scopemeter. Three different frequency values were used to test the frequency and amplitude loss 1 Khz, 10 Khz, and 1 Mhz. For each trial, the amplitude of the wave was set at around 10 volts peak to peak and was wrapped around wooden dowels ranging in diameter from 1" to 1/8" in 1/8" increments. The values were recorded and the amplitude of the wave was then set to 5 volts peak to peak and the same process was repeated to find the amplitude loss with this new constant amplitude value. This process was done with the three different frequencies. The percentage of amplitude lost was then calculated for each trial.

The results of my experiment did not support my hypothesis. When transmitted through a fiber optic cable with a smaller degree of bend diameter, the signal lost only amplitude and the frequency was unaffected. The highest percentage of loss of amplitude occurred when the signal was transmitted through the cable with a constant amplitude of 5 volts peak to peak. Regardless of the bend diameter, the amplitude loss percentage was still greater than the signal with the constant 10 volts peak to peak amplitude with the same bend diameter.  

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