Preamplifier?BNC adapter Nor1447/ L0 pages
Product Data
Preamplifier–BNC adapter
Nor1447/L
The adapter Nor1447/L consist of a
normally
self noise of a preamplifier or a sound
screened capacitor for connecting a
ships with a coupling capacitance of
The
Nor1447
adaptor
level meter, as specified in international
signal to a 1/2” microphone preamplifier
18 – 20pF which corresponds to the
standards for sound level meters IEC
like Nor1201. A BNC socket is used as
capacitance of most 1/2” microphones.
60651 and IEC61672.
the input terminal.
The device may therefore be used to test
On order, the unit can be delivered
The main application of the adaptor is
the frequency response of a preampli-
for the testing of preamplifiers and sound
fier, but be sure to use a source imped-
level meters as described in iec 60651
ance corresponding to a microphone
the adapter with a very low attenuation
and iec 61672, but it may just as well be
cartridge. If the BNC input connector
since the stray capacitance is low. The
used to connect a transducer like an ac-
is short-circuited, the device may also
Nor1447/L has a very low capacitance
celerometer to the high impedance input
serve as a microphone cartridge equiv-
and is mainly used to measure the input
of a microphone preamplifier.
alent (“dummy microphone”) to test the
capacitance of a microphone preamplifier.
with other capacitance values.
The
screened
design
provides
Specifications:
External diameter: 12,7±0,1 mm
Internal diameter for thread:
11.7 mm
Thread: 60 UNS-2B
Maximum voltage: 200 V
Input connector: BNC
Preamplifier interface:
Preamplifiers compatible with
the mechanical requirements of
IEC61094-4: Measurement microphones, Part 4, Specifications for
working standard microphones.
The inner shield
Threads to fit
preamplifier
(to make it act
like a cartridge)
The outer shield
Inner shield is connected to
signal on the low impedance
side – this will reduce stray
capacitances drastically
Capacitance: Normally 1–3 pF,
individually calibrated. Other values
in the range 2–1000 pF on request.
Stray capacitance (BNC input –
ground): 11 pF typically
Other versions available:
1147/1: C= 40 pF (1/1” mic. equivalent)
1447/2: C= 20 pF (1/2” mic. equivalent)
1447/4: C= 6.8 pF (1/4” mic. equivalent)
Certificate of calibration
Adapter type Nor1447
Serial No.:
Capacitance:tt
pF
Sign:
PD 1447/1 Ed.2 Rev.0 English 11.09
Inner shield is insulated
from the casing
Capacitor
BNC connector
in this end