Psophometric voltage is a circuit

Electronic circuit

An electronic circuit is composed of individual electronic components, such as resistors, transistors, capacitors, inductors and diodes, connected by conductive wires or traces through which electric current can flow...

 noise voltage

Voltage

Voltage, otherwise known as electrical potential difference or electric tension is the difference in electric potential between two points — or the difference in electric potential energy per unit charge between two points...

 measured with a psophometer

Psophometer

In telecommunications, a psophometer is an instrument that provides a visual indication of the audible effects of disturbing voltages of various frequencies.A psophometer usually incorporates a weighting network...

 that includes a CCIF-1951 weighting network

Weighting filter

A weighting filter is used to emphasise or suppress some aspects of a phenomenon compared to others, for measurement or other purposes.- Audio applications :...

.

"Psophometric voltage" should not be confused with "psophometric emf," i.e., the emf in a generator or line

Line (electrical engineering)

In electrical engineering, a line is, more generally, any circuit of an electrical system. This electric circuit loop , consists of electrical elements connected directly by conductor terminals to other devices in series....

 with 600 Ω internal resistance. For practical purposes, the psophometric emf is twice the corresponding psophometric voltage.

Psophometric voltage readings, V, in millivolts, are commonly converted to dBm

DBm

dBm is an abbreviation for the power ratio in decibels of the measured power referenced to one milliwatt . It is used in radio, microwave and fiber optic networks as a convenient measure of absolute power because of its capability to express both very large and very small values in a short form...

(psoph) by dBm(psoph) = 20 log₁₀V- 57.78.