Tim Williams wrote:

"Michael A. Terrell" wrote in message
...
dB without a reference is meaningless. How can you have a ratio
without a reference?

Easy. "dB" in general usually refers to acoustic power, where the reference
is some ungodly small power level (10^-12W/m^2 IIRC?).

I forget if there's a similar radio context used...


You need to do a lot of studying on how to use the dB. Without a
reference, it is meaningless. The classic use in audio was 1 mW into
600 Ohms = 0 dBm, and yes, there are a number of RF uses for the dB.
Either in reference to one of several different reference levels, or as
an absolute ratio, such as the input to output level of an amplifier.

--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida