Oscilloscope adaptor

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

• 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: V_out=V_in*(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.