Free Space Optics is a medium with high bandwidth which has maximum data rate. Demand for large data speed capacity has been increasing exponentially due to the massive spread of internet services. So with the growing transmission rate and demand in the field of optical communication, the electronic regeneration has become more expensive. With the introduction of power optical amplifiers the cost of converting optical signals to electronic signals has been brought down immensely. This research paper describes the effect of varying duty cycle on BER performance of the FSO link with hybrid amplifier having different attenuation.