6. TEST CERTIFICATION
6.2. Design input: The input signal was generated using a function generator because it was easy to set the input frequency. The function generator gave us the exact input we needed for the design. This was simply done by hooking a function generator up to the input of our design. Also the oscilloscope was used to monitor the input signal from the function generator.
6.2. Design output: The output signal was tested and measured by using an oscilloscope and digital multimeter. All we had to do was to observe the output on both the oscilloscope and multimeter.
6.3.Temperature/heat: The voltage rails used were big. The heat dissipated by circuit was high. However, throughout the testing and implementation the amplifier was always attached to the heat sink and the cooling fans were always on. We did not allow the heat dissipated by the amplifier to affect or circuit or output. Just to measure the amount of heat dissipated, we ran the amplifier at full load for ten minutes without the heat sink and measured its temperature, and it was 169oF. The temperature met our constraints.
6.4. Harmonic distortion: The harmonic distortion of the circuit
was tested only in our Pspice simulation. Our target of 0.1 % (THD) was met on the schematic level. However, we could not physically measure the THD of our amplifier because we did not have the equipment to measure it.
Frequency response: The frequency response of the amplifier was measured manually. When the amplifier was in operation we varied the frequency from about 1Hz to 10kHz and calculated the gain. A graph of the gain vs. frequency was plotted to show the type of frequency response we were getting from the amplifier. We had a flat response from .95Hz to 9.5kHz.