Model 820 Technical Reference Manual
Detector Time Weightings
A-7
Detector Time Weightings
The available RMS detector time weightings are FAST,
SLOW, and IMPULSE. There are also two available PEAK
detectors (Weighted Peak, Unweighted Peak).
• Weighted Peak Detector Rise Time: 60 µs
• Unweighted Peak Detector Rise Time: 30 µs
Effects of Temperature
The SPL level varies ð 0.5 dB when the complete instrument is
tested over the -10° C to 50° C temperature range. The refer-
ence reading, for this test, is taken at 20° C and 36% relative
humidity (RH); the input signal is at 1000 Hz.
Effects of Humidly
The SPL level varies ð 0.5 dB when the complete instrument is
tested over the 30% to 90% RH range. This test is performed
at 40° C, with an input signal of 1000 Hz.
Limits of Temperature and Humidity
Permanent damage can occur when stored or operated above
60° C or below -20° C. Condensation of moisture will make
readings inaccurate but will be correct when moisture has dis-
sipated.
Microphone Extension Cables
When measuring signals below 20 kHz, up to a 12 foot micro-
phone extension cable may be used with the Model 820.
