Larson Davis System 824, Техническое справочное руководство

Страница: 200 / 673

6-6 824 Reference Manual 9/29/09
The two possible output signals are on the tip and the ring of
the 3.5mm jack. The sleeve is ground. The selection in the
824 controls settings lists the signal output on the tip first,
followed by the signal output on the ring. The AC output
signal is always amplified or attenuated by the gain or
attenuation selected for the instrument. For example, if one
were using an SSA instrument with 20dB of gain, the AC
output would also have 20 dB of gain from the input*.
*Also take into account a gain of
approximately -0.25 dB in the
PRM902 preamplifier. The DC output voltage is proportional to the SPL specified
by the weighting setting according to this formula
StartLevel is a setting on the Ln settings menu. DC out has a
range of 120 dB.
The output signals will vary based on which instrument type
is used. For LOG and ISM instruments, the following table
defines the output signals.
For SSA instruments, the following table defines the output
signals
(output amplitude based on input Gain setting).
SPL Vout
( )
0.0275
⁄ ( )
StartLevel + =
LOG and ISM Instrument AC and DC Output Settings
824 Menu 3.5mm Connector Tip (Black) 3.5mm Connector Ring (red)
AC-1 AC-2 FLAT AC out FLAT AC out with 30dB gain
AC-1 DC FLAT AC out Weighted DC out
AC-2 DC FLAT AC out with 30 dB gain Weighted DC out
AC-2 AC-1 FLAT AC out with 30 dB gain FLAT AC out
SSA Instrument AC and DC Output Settings
824 Menu 3.5mm Connector Tip (Black) 3.5mm Connector Ring (red)
AC-1 AC-2 FLAT AC out CWT AC out
AC-1 DC FLAT AC out Weighted DC out
AC-2 DC CWT AC out Weighted DC out
AC-2 AC-1 CWT AC out FLAT AC out