Differences
This shows you the differences between two versions of the page.
| Both sides previous revision Previous revision | Next revision Both sides next revision | ||
|
wind_sensor:meeting_minutes_may_19_2017 [2017/05/20 00:35] mwu [Ultrasonic Wind Sensor] |
wind_sensor:meeting_minutes_may_19_2017 [2017/05/20 01:12] mwu [Ultrasonic Wind Sensor] |
||
|---|---|---|---|
| Line 7: | Line 7: | ||
| * Implemented non-inverting amplifier with DC bias. Currently attempting to send just one pulse, so using a gain of about 110 V/V. {{ :wind_sensor:one_pulse_amplifier.jpg?direct&600 |}} | * Implemented non-inverting amplifier with DC bias. Currently attempting to send just one pulse, so using a gain of about 110 V/V. {{ :wind_sensor:one_pulse_amplifier.jpg?direct&600 |}} | ||
| * The disadvantage to having this amplifier is that the noise is also amplified which causes the voltage comparator to trigger falsely. | * The disadvantage to having this amplifier is that the noise is also amplified which causes the voltage comparator to trigger falsely. | ||
| - | * Attempting to use the Schmitt Trigger to "qualify" the signal before registering it as a valid response. This should solve the above problem. | + | * Attempted to use the Schmitt Trigger to "qualify" the signal before registering it as a valid response. |
| + | * The trigger's threshold levels were experimentally determined to be: Vth = 1.95V, Vtl = 1.15V. The idea was to center the signal at one of the thresholds and use the other threshold as the trigger. This would've solved the issue since the signal would have to satisfy one threshold before it changes the output of the trigger (qualification). | ||
| + | * The signal was centered at 1.95V, but the result was inconsistent. Sometimes the signal would register while other times it wouldn't. | ||
| * To Do: | * To Do: | ||