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Decibel Calculator

A decibel calculator for the ham.

Computing decibel values from power or voltage can be an intricate task.


For example:

You know two power values, what is the decibel value?

You know two voltage values, and what is the decibel value?

You know one power or voltage value and a decibel value, what is the other power or voltage?

You know a transmitter's output power and the SWR, how much power will be reflected?


This screenshot shows an example, known two power values 85 and 1000 Watts, the decibel relation between them is calculated to 10.7 dB.

If your output power is 100 W on a transmission line with antenna showing a VSWR of 2.2:1, the reflected power will be 14.1 W.


The same goes for the other dB approaches in the calculator.

Download the decibel calculator here, it's free, and needs no installation - just put the program in a folder of your choice!
(, 209kB)