How do I Calculate the Ratio of Two Voltages in Decibels Using the DLM2000 User-Defined Math?

For the DLM2000 with user-defined math (G2 Option), you can calculate the ratio of two voltages in decibels. The formula for calculating the ratio of two voltages in dB is:

                  dB = 20*Log(Voltage1/Voltage2)

Follow the procedures listed below to perform the calculation:

  1. Press MATH/REF » Mode » Math1 soft buttons to select CH1 math
  2. Press Operation » User Define soft buttons to set the operation to user defined math
  3. Press Expression soft button and enter the formula:
  4. Press Enter to confirm the expression

Please view the attached file for an example screenshot and the calculation result.

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