Accelerometers; Microphone Power Supplies - B&K 2627 Instructions And Applications

The Condenser Microphone Type 4148 can not be used with more than
120 Volts Polarization.
The Piezoelectric Microphone Type 4117 can not be used with the
Type 2627 Preamplifier.
~2.ACCELEROMETERS
All 8 & K accelerometers may be used with the Type 2627 Preamplifier
provided the adapters JJ 2612 and JP 0028 are used. The JJ 2612 adapter is
provided with the Type 2627 Preamplifier. The adapter JP 0028 allows the
connection of the 8 & K accelerometer cables to the 2627.
The voltage sensitivity of the accelerometers, complete with cable, is
given in the calibration chart supplied with each accelerometer. If a cable
different from the one used in the calibration, is employed, then the voltage
sensitivity of the new combination will be different from that given on the
calibration chart. The new sensitivity Sv' is given by
where
s '
v
Sv
Sv (Ct
+
Cc)
(Ct
+
Cc')
the calibrated voltage sensitivity with cable
capacitance Cc
the accelerometer capacitance
the new cable capacitance.
4.3. MICROPHONE POWER SUPPLY TYPES 2801 & 2807
The Microphone Power Supplies are intended for use with the 8 & K
condenser microphones and preamplifiers where 8 & K Measuring Ampli-
fiers or Analyzers are either not available or not necessary.
The Type 2801 is a single channel power supply. The Type 2807 is a two
channel power supply with a built-in attenuator. The two channels may be
used simultaneously or either channel may be selected by manual or auto-
matic (internal or external) switching to enable only one set of instrumenta-
tion to be used at the output.
The power supply units are heavily stabilized for variations in line voltage
and may be operated from power out lets in a voltage range 1 00 to
240 Volts (50 to 400 Hz).
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