Larson Davis System 824, Техническое справочное руководство

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F-6 824 Reference Manual 9/29/09
1
Combination of electronic and thermal noise of the
microphone at 20
°
C measured in a sealed cavity and
vibration isolated.
2
Electronic noise of the instrument with an ADP005 adaptor
in place of the microphone
Maximum Sound Pressure
Level:
The highest sound pressure level the Larson Davis 824 is
designed to accommodate at the level of overload is 128 dB.
The peak-to-peak voltage at this level is 6.25 Vpp input
through the ADP005.
Power Supply Voltage Range:
The battery power supply voltage range for which the
System 824 conforms to this standard is 2.3 to 4.8 volts.
The System 824 will shut down if the battery is below 2.3
volts when used with alkaline batteries and below 3.3 volts
when used with NiMH batteries.
Display Device
The display device will display all levels over the entire
linear operating range on all ranges.
Stabilization Time Following
Changes of Environmental
Conditions:
The typical time interval needed to stabilize after changes in
environmental conditions is as follows:
• For a temperature change of 5
°
C, the time is 30 minutes
• For a static pressure change of 5 kPa, 15 seconds
• For a humidity change of 30% (non-condensing), 30
minutes
Electric Field Strength Above
10 V/m:
The Larson Davis model 824 was not tested for field
strengths greater than 10 V/m.
Greatest Radio Frequency
Emission Levels:
NOTE: For the specification of emission
of and susceptibility to, radio frequency
fields, the System 824 is classified as
group X sound level meter.
The mode of operation of the 824 that produced the greatest
radio frequency emission levels was with the 824 set to ISM
mode and with an EXA010 (10' microphone extension
cable) used to connect the PRM902 to the 824. All ranges
were the same. Radio frequency emission in other modes