Svantek SVAN 979, Руководство пользователя

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SVAN 979 User Manual - Appendixes
Mounting for acoustical tests
The microphone must be mounted on the preamplifier.
Preamplifier can be connected with SVAN 979 in two ways:
•
directly attached to the meter or
•
with the SC 93/5 extension cable (with the microphone preamplifier holder mounted on tripod).
Electrical substitute for the microphone To obtain a BNC Class electrical input, the microphone
must be replaced by an electrical microphone impedance
ST 02 with the serial capacitance 18
pF ± 10%.
Note: For the electrical conformance tests or the conformance tests with the acoustic coupler, all
compensation filters must be Off (path: <Menu> / Measurement / Compensation Filter).
Note: For the conformance of acoustical tests, the Free Field compensation filter should be switched
on and the Windscreen position must be Off (path: <Menu> / Measurement / Compensation Filter).
If the case of Windscreen testing the Windscreen position must be On.
Note: Installation of the SC 93 preamplifier extension cable is automatically detected by the
instrument. When SC
93 is installed the “case compensation” filter is switching off.
Periodical test upper frequency 8 kHz
Linear Operating Ranges
Two measurement
ranges are available: “LOW” and "HIGH".
The starting point at which tests of level linearity shall begin is 94.0 dB for the frequencies specifies below.
Table C.1.1. Linear operating range:
“LOW” for the sinusoidal signal and microphone sensitivity 50 mV/Pa
[dB]
L
AS/F
L
BS/F
L
CS/F
L
ZS/F
L
AeqT
L
BeqT
L
CeqT
L
AE
L
Cpeak
(t
int
= 2 s)
from to from to from to from to from to from to from to from to from to
31,5 Hz
22 80 22 103 22 117 38 120 22 80 22 103 22 117 25 83 50 120
500
Hz
22 116 22 119 22 120 38 120 22 116 22 119 22 120 25 119 50 123
1 kHz
22 120 22 120 22 120 38 120 22 120 22 120 22 120 25 123 50 123
4 kHz
22 121 22 119 22 119 38 120 22 121 22 119 22 119 25 124 50 122
8 kHz
22 119 22 117 22 117 38 120 22 119 22 117 22 117 25 122 50 120
12.5
kHz
22 115 22 114 22 114 38 120 22 115 22 114 22 114 25 118 50 117