answersLogoWhite

0


Best Answer

The Bel is far too large for most use, so deciBels have wider application. The upper case has now been dropped except in the abbreviated form. Normally the decibel or dB should always be followed with the reference that the ZERO represents for the simple reason that the reference is variable. It should have been written 0dB wrt 1mW in 600 ohms for the situation it possibly describes. (wrt means, with reference to.)

The normal form is 0dBm or 0dBA or even 0dBV etc, notice how the uppercase returns. The decibel scale is a log scale allowing very wide dynamic changes to be represented, both graphically and intellectually. In the short form, such as 0dBm, the "m" has become an identification for " --wrt-- 1mw in 600 ohms." Similarly with dBV where the reference is one volt. There is a 3dB difference between POWER and VOLTAGE figures so where 6dB represents a change of two in voltage, in power the same doubling, (or halving) is 3dB.

0 dBA represents the threshold of human hearing, often described as a cricket shuffling it's feet in the grass at your feet. This would mean that normal speaking level is about +65 dBA and a jet engine say, +125 dBA. Double or half the power would be a change of 3dB.

User Avatar

Wiki User

14y ago
This answer is:
User Avatar

Add your answer:

Earn +20 pts
Q: What is mean by 0 decibel?
Write your answer...
Submit
Still have questions?
magnify glass
imp