What does 0 decibel millivolt (dBmV) equal?

0 decibel millivolt (dBmV) is defined as the voltage level in millivolts (mV) referenced to a specific load impedance. In the case of 0 dBmV, it equals 1 mV when measured across a 75-ohm load. This is a standard reference in the telecommunications industry, particularly in the context of cable and RF systems, where 75 ohms is a common characteristic impedance for coaxial cables used in video distribution and cable television.

The decibel millivolt scale is a logarithmic representation of the actual voltage, and 0 dBmV indicates a baseline measurement where the signal is exactly 1 mV. Hence, when dealing with measurements in decibel millivolts, it is essential to know the impedance across which the voltage is referenced, as it can change the effective voltage readout.

In summary, 0 dBmV corresponds to exactly 1 mV across the standard 75-ohm load, making it the correct interpretation of the unit in this context.