1. Wave Solutions Inc. “Power Amplifier” Final Project By: Bryan Garofalo, KonradGornicki, Xiang Lin, GuilhermeMota, Andrew Small
2. Assembly Attempted to improve on given schematic fro pre-amp and was unsuccessful. Proto-board layout was organized and making sure of the proper component values was key. Also we minimized the amount of connecting wires in order to easily trouble shoot the circuit and cut down on noise. Both amps driven by the same power source. Power–amp assembly adjusted.
5. Testing Testing of each amp was performed separately. Initial testing of Power amp produced only positive wave signal. Pre-amp output had a large amount of noise. When combined using one input source, the completed amp had some noticeable noise as seen on the oscilloscope.
6. Alterations Power amp Adjusted (resistor value 12k to 6.8k). Capacitors added to Pre-amp and Power amp in order to filter out certain higher frequencies contributing to noise (1 micro F). In order to cancel cascading noise through the amplifiers, each Amp was driven off of a separate input (proto-board).
7. Final Testing After alterations, the completed amp worked as expected. Further testing was done to emphasize the properties of the amp. Speaker replaced with a load resistance, Voltage output was only nominally affected showing the reactance looking into the amp was much greater than the load resistance (stability). By placing an audio signal through the power amp alone, the function of the pre-amp was noted (Lows and highs were missing without pre-amp).
12. Conclusion The function and necessity of the pre-amp was noted by driving an audio signal through the power amp alone. A respect for the intricacies of circuit design was gained as we had to alter the circuit in certain ways in order to get the amp to. function optimally. Our Amplifier worked and was relatively efficient.
13. Conclusion The efficiency of our complete amplifier was calculated using the following values: Input: I= 275mA V(peak to peak) = 24V P= IV Pin= 6.6Watt Output: V(peak to peak)=18V V(rms)= 6.36Vrms R(load)= 10Ω P=V2/R= 6.362/10 Pout = 4.05W Efficiency = Pout/Pin = 4/6.6 Efficiency= 61.4%
