Second Coil Test and Success!

The second iteration of testing the prototype was a success. We re-coiled the transmitting coil to give it a stronger hold on the container as well as add a few more turns for transmission strength. The test circuit was very basic, as shown in figure 1. The output signal was identical to the input signal in frequency, but varied in phase and amplitude. In figure 2, the received signal is shown in yellow on top and the transmitted is shown in green on the bottom.
To test the effectiveness of this system in a metal detecting capacity, we held metal objects over the coils and saw what happened on the oscilloscope screen. The result was a small change in amplitude on the receiving coil, but no perceptible change in phase was seen.


Figure 1: Test Circuit Diagram

Figure 2: Transmitted and Received signals

Figure 3: Circuit setup

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