User Interface:
System Level Specifications and Features:
Test Conditions:
1. To test the input power requirements, the circuit will be supplied
with AC power from the wall outlet (into a laboratory
DC power supply) and measure the power drawn
in all operating modes.
2. To test the audio input range, a function generator will be
connected to a speaker (with the proper matching network and power
driver) to produce audible sine, square, and
triangle wave tones from 50 cents flat of C0 to 50 cents sharp of B9 at
the minimum
and maximum amplitudes and verify that the
displays give the correct information in both Manual and Auto tuning modes
within
the maximum response time.
3. To test the audible output, a microphone will be connected
(with appropriate matching networks) to an oscilloscope, and
observe the output for all available pitch
settings.
Senior Project Demo:
In order to verify correct operation of the auto-chromatic tuner, tests must be performed for all modes over the entire range of operation. In other words, the capabilities of the tuner over the range from C0 to B9 must be tested in Auto Tuning, Manual Tuning, and Audible Reference Pitch mode. One practical way to do this would be to connect a function generator to a speaker, which would then sound pitches over the entire range as frequencies were adjusted. A test from a function generator, however, will not be complete. Testing the tuner using actual musical instruments would be a good test, as well. Since I play clarinet, I can bring in my instrument for testing purposes. There are several other electrical engineering majors who play instruments whom I could ask to play into the tuner for a wider variety of sound. The audible reference pitch mode could be tested against a tuner out on the market that covers a comparable range. Also, the Audible Reference Pitch mode should be tested to make sure all of the notes over the range can be heard adequately for tuning by ear. As notes are sounded from a musical instrument or function generator, the Auto Tuning and Manual Tuning modes can be tested. In Auto Tuning Mode the user can play notes and see whether the closest concert pitch is displayed and evaluated correctly. Similarly, Manual Tuning mode may be tested by setting the tuner to a wide variety of pitches, then assuring that the corresponding pitches on the musical instrument coincide.