Attended: Mengyuan, Creighton, Scott

• Updates:
• To Do:

• Updates:
  • Built an amplifier and placed it in between the 40kHz square wave output of the 555 timer circuit and the emitter. Hooked up the signal at the output of the amplifier to an oscilloscope as well as the signal at the receiver. Our experimental setup as well as the results are shown below:
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    • Our results were problematic. For one, the output of the amplifier was heavily distorted (it should've been a clean square wave), though the amplitude was still around 13Vpp (which it should've been). Furthermore, the received signal was much weaker than expected. We were only getting 72mVpp, when we expected much more.
  • Developed an algorithm that involves using the Teensy to generate the 40kHz square wave instead of using the 555 timer. This is mainly due to avoid the possibility of a current bottleneck with trying to drive the transducer using the 555 timer.
    • The algorithm involves the Teeny sending 10 25us pulses and then using thresholding and ADC to record the pulses. Since the tof of a pulse is longer than the time it takes the Teensy to send the pulses, we don't have to worry about potentially trying to record while still sending. Average a bunch of samples and we should have a result.
• To Do: