[TenTec] dbm and VU units of audio measurement

["Tom North" <tomnorth@airmail.net>]

Lots of confusion abt how the dB standard has been applied and used over the
years. My HP-606A SG uses the DBM range referencing 0db=10 dB below 1V (.3V)
into a 50 Ohm load. This has been a standard for some years, but impedance
can throw a curve.

dBm referenced to 1 mV as a unit of power is pretty well spelled out, both
in reason and formula, in the ARRL Handbook; page 17.2 in the 1999 edition.
Used as a reference, for reasons discussed in the handbook, for very low
power levels. Ran across it in use most recently with a MMIC device
associated with TT's little RF preamp kit.

GL & 73'

Tom  N5OZQ