BRUEL & KJAER 2672, Руководство пользователя

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Chapter 2 — Controls and Connectors
Front Panel
Sound Quality Conditioning Amplifier Type 2672
User Manual
BE 1461 –11
2
−
3
2.1.3 Input
Select: Two 3-position sliding switches for selection of:
Pre.: Preamplifier input via Preamp. connector.
Dir.: Direct input via Dir./CCLD connector.
CCLD: Constant current line drive input via Dir./CCLD connec-
tors for use with DeltaTron
®
preamplifiers.
Preamp.: Two 7-pin LEMO connectors for input of preamplifier signals
from, for example, Head and Torso Simulator Type 4100. The con-
nectors also provide the microphone polarization voltage and
charge injection calibration signal. Pin designations are given in
Fig.2.2.
Pin
1 Calibration output
2 Signal ground
3 Pol. voltage
4 Signal Input
5 Not connected
6 Power supply positive
7 Power supply negative/ground
Casing Connected to instrument chassis
Fig.2.2 Pin designations for 7-pin LEMO
Preamp. connector (external view)
Dir./CCLD: Two BNC connectors for input of direct (electrical) signals, or sig-
nals from DeltaTron
®
preamplifiers as used, for example, with
Head and Torso Simulator Type 4100 D. The connector provides a
constant current of 4 mA. The function of the connector is deter-
mined by the position of the Setting switch.
Pol. Voltage: 3-position sliding switch for selection of 0, 28 or 200 V microphone
polarization voltage.
Note: The same polarization voltage is applied to both left- and
right-hand channels.
CIC: 4-position sliding switch for selection of the signal to use for
charge-injection calibration (CIC) of Head and Torso Simulator
Type 4100. The signal is applied to both Preamp. inputs (see
Fig.2.2). Settings are:
1 6
2
3 4
7 5