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I am trying to determine the average dBA of a key fob. I found on your website, from a previous Q&A session, that the frequency of a key fob is approximately 315 mHz +/- 2.5 mHz. Can decibels be calculated from frequency? If so, can you please offer the equation and an explanation?

Thank you for your time!

Can decibels be calculated from frequency?

NO, the frequency does not force the amplitude. You can have 120 volt at 60 Hz, or 2.2 kV at 60 Hz, as example, same frequency, different amplitude.

YES, in part, since dbA is about the perception from a human point of view and the perception can differ when the frequency is changed. But again, the frequency ALONE does not define de source.

Thank you for your response. If the maximum allowable dBA is 76, then would the average frequency of the key fob (315 mHz +/- 2.5 mHz) exceed the maximum allowable dBA? If there is not enough information to figure out the solution, do you know where I can begin searching. I have looked everywhere for the average dBA of a key fob and can't find anything.

There are somehow a reference scale at many sites, such as at Noise Level Chart where you can compare your case with the supplied examples ( a little bit like Richter scale was for a long time about earthquacke).

Thanks again and I appreciate your help! I will check the Noise Level Chart and see what I can find there.

Actually I just realized that I am looking for the dBA a vehicle makes when it is being unlocked with a key fob, not the key fob itself, DUH! Anyway, thanks for your help.