Oscilloscope adaptor

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Goal: To take input from .3-16v to .3-2.0v

Ideas:

Voltage Divider w/ Zener

  • Use a resistor-based voltage divider that divides by eight, reducing 16 volts to 2 volts.
    • Using precision surface-mount resistors on a PCB with a heat-sink
      • Use body of probe as heatsink, if conductive enough.
  • Use a 2v zener diode with a voltage dependent switch to enable the measuring of voltages less than 2.4v(.3*8)
    • This method would require the child to recognize high(above 1.9v) and low(below 1.9v) voltages, and to adjust a switch accordingly.

Prototype

Schematic of a resistor divider. R1 is connected to Vin and Vout, R2 is connected to Vout and GND

  • Using a voltage divider like the one imaged above, I set the values of R1 to be 700 ohms, and R2 to be 100 ohms, according to the formula: Vout=Vin*(R2/(R2+R1))
    • This gives me a simple voltage divider which divides by a factor of 8
  • I then plan on having a simple switch to switch the path of the input from the voltage divider to a 2v Zener diode.
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