what is difference between pre- amplifier and post- amplifier (booster)?
Answers
Pre amps are primarily used very next to input device like microphone etc. Preamp amplifies signal just balanced enough to be fed to next amplification stage. Power amps drive the Speaker directly. Most amplifiers have preamp built-in the main circuit.
Pre-Amplifier is usually installed at the receiver end of the DWDM network to amplify the optical signal to the required level to ensure that it can be detected by the receiver. The following picture shows a typical diagram for a duplex 10G DWDM network that can support 80km. A pre-amplifier is installed at each receiving end of this network. There will be great power loss after the optical signal goes through the 80km optical fiber. Then, a pre-amplifier installed at the receiver end is necessary. Generally, a pre-amplifier should offer high gain to ensure that the optical signal is detectable.