Active Filters / Aktiva Filter
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Suppliers/ Leverantörer:
Benchtop/Rack Mountable 1, 2 and 4 Channel Models:
| Model 3360 Series |
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0.1 Hz to 200kHz
1, 2 and 4 Channel/4-Pole Butterworth/Bessel
Low-Pass/High-Pass/Band-Pass/Band-Reject
EACH CHANNEL PROVIDES
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DESCRIPTION
The Krohn-Hite Model 3360 Filter Series are one, two or four channel filters
providing ease of operation and the reliability Krohn-Hite has been known
for since 1949; along with a price that will fit any budget.
The 3360 Series provides a tunable frequency range from 0.1Hz to 200kHz,
and with the 002 option, the range is extended to 0.005Hz. The frequency
response characteristic is selectable to either maximally flat (Butterworth)
for clean filtering in the frequency domain, or linear phase (Bessel)
to provide superior pulse for complex filtering.
Each channel of the 3360 Series is a selectable low-pass or high-pass,
4-pole filter providing an input gain to 50dB, and an output gain to 20dB
selectable in 0.1dB steps. The 3360 Series will accept input signals to
±10V peak at 0dB gain and has selectable ac or dc coupling. Memory
is available for storing a set-up of the instrument which can be recalled
with a simple command.
| Model 3380 Series |
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0.1 Hz to 200kHz
1, 2 and 4 Channel/4-Pole Butterworth/Bessel
Low-Pass/High-Pass/Band-Pass/Band-Reject
EACH CHANNEL PROVIDES
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DESCRIPTION
The Krohn-Hite Model 3360 Filter Series are one, two or four channel filters
providing ease of operation and the reliability Krohn-Hite has been known
for since 1949; along with a price that will fit any budget.
The 3360 Series provides a tunable frequency range from 0.1Hz to 200kHz,
and with the 002 option, the range is extended to 0.005Hz. The frequency
response characteristic is selectable to either maximally flat (Butterworth)
for clean filtering in the frequency domain, or linear phase (Bessel)
to provide superior pulse for complex filtering.
Each channel of the 3360 Series is a selectable low-pass or high-pass,
4-pole filter providing an input gain to 50dB, and an output gain to 20dB
selectable in 0.1dB steps. The 3360 Series will accept input signals to
±10V peak at 0dB gain and has selectable ac or dc coupling. Memory
is available for storing a set-up of the instrument which can be recalled
with a simple command.
Benchtop/Remote Controlled/Rack Mountable 1 to 4 Channel
Models:
| GPIB Programmable Tunable
Active Filters Model 3900 |
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1Hz to 99kHz
Dual Channel Low-Pass Elliptical Filter
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INTRODUCTION
The Krohn-Hite Model 3900 programmable, dual channel Elliptical filter/voltage
gain amplifier is one of a family of new programmable filters from Krohn-Hite.
As an elliptical filter, the Model 3900 has two independent filter channels
that have a tunable cutoff frequency range from 1Hz to 99kHz and a rolloff
rate of 115dB/octave. Each filter section has a minimum stopband attenuation
of >80dB and a passband ripple of typically 0.22dB.
The 3900 provides either a single-ended or differential input with a common
mode rejection of >60dB. Input gains up to 40dB in 10dB steps and output
gains to 20dB are also provided. The 3900 will accept input signals of
±10V peak at 0dB gain and has selectable ac or dc coupling. The
filter is GPIB Bus programmable and is complimented with non-volatile
memory for the storage of up to 99 front panel set-ups. Overload detectors
are standard and assist the user in detecting excessive input signals
or incorrect gain settings.
AMPLIFIER FEATURES
The 3900 is also a programmable voltage gain amplifier for applications
that require a low noise amplifier. The amplifier has a bandwidth of 1MHz
and gains to 60dB, selectable in 10dB steps, and a wideband noise of <100µV.
| GPIB Programmable Tunable
Active Filters Model 3901 |
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1Hz to 99kHz
Elliptical Filter - Two Channel High-Pass/Low-Pass
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As an elliptical filter, the Model 3901 has two filter channels that
have a tunable cutoff frequency range from 1Hz to 99kHz and a rolloff
rate of 115dB/octave. Each channel can be used independently; one as a
high-pass filter and the other as a low-pass filter; or the channels can
be externally connected for band-pass (series) or band-reject (paralleled)
operation. Each filter section has a minimum stopband attenuation of >80dB
and a passband ripple of typically 0.22dB.
The 3901 provides either a single-ended or differential input with a common
mode rejection of >60dB. Input gains to 40dB in 10dB steps and output
gains to 20dB are also provided. The 3901 will accept input signals of
±10V peak at 0dB gain and has selectable ac or dc coupling. The
filter is GPIB Bus programmable and is complimented with non-volatile
memory for the storage of up to 99 front panel set-ups. Overload detectors
are standard and assist the user in detecting excessive input signals
or incorrect gain settings.
AMPLIFIER FEATURES
The 3901 is also a programmable voltage gain amplifier for applications
that require a low noise amplifier. The amplifier has a bandwidth of 1MHz
and gains to 60dB, selectable in 10dB steps, and a wideband noise of <100µV.
| GPIB Programmable Tunable
Active Filters Model 3940 |
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3Hz to 2MHz
Two Channel High-Pass/Low-Pass
Butterworth/Bessel Filter
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DESCRIPTION
The Krohn-Hite Model 3940 programmable, dual channel, Butterworth/Bessel
filter offers a programmable or benchtop filter covering a cutoff frequency
range from 3Hz to 2MHz. It has a frequency response characteristic of
maximally flat (Butterworth) for clean filtering in the frequency domain,
or linear phase (Bessel) to provide pulse signal filtering. The passband
gain is unity, and the attenuation slope is 24dB/octave per channel. The
3940 will accept input signals of ±4.5V peak and provides input
and output gains of 0dB or 20dB which can be selected via the front panel
keyboard or over the GPIB bus.
CONFIGURATIONS
The filter can be programmed to operate in low-pass, high-pass, band-pass
or band-reject modes, or the two channels can be interconnected to achieve
48dB/octave high-pass or low-pass slopes.
STORING SET-UPS
The Model 3940 offers to the user 99 groups of non-volatile memory for
storage of front panel set-ups, which are stored in battery-backed CMOS.
Set-ups can then be recalled with a simple command.
The 3940 also provides a self-test diagnostics upon power-up of its internal
memory to insure the unit is operating properly. If a failure occurs,
the display will indicate which ROM or RAM has failed.
| GPIB Programmable Tunable
Active Filters Model 3944 |
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3Hz to 2MHz
Four Channel High-Pass/Low-Pass/Band-Pass/Band-Reject
Butterworth/Bessel Filter
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DESCRIPTION
The Krohn-Hite Model 3944 is a 4-channel, Butterworth/Bessel filter offers
a programmable or benchtop filter covering a cutoff frequency range from
3Hz to 2MHz, with a frequency response characteristic of maximally flat
(Butterworth) for clean filtering in the frequency domain, or linear phase
(Bessel) to provide superior pulse or complex signal filtering. The passband
gain is unity, and the attenuation slope is 24dB/octave per channel. The
3944 will accept input signals of ±4.5V peak and provides input
and output gains of 0dB or 20dB which can be selected via the front panel
keyboard or over the GPIB bus.
CONFIGURATIONS
The filter can be programmed to operate in any combination of four channels
of high-pass or low-pass; two channels of any combination of band-pass
or band-reject; or one channel of band-pass or band-reject and two channels
of any combination of high-pass or low-pass. The four channels can be
connected to achieve 96dB/octave of high-pass or low-pass.
STORING SET-UPS
The Model 3944 offers to the user 99 groups of non-volatile memory for
storage of front panel set-ups, which are stored in battery-backed CMOS.
Set-ups can then be recalled with a simple command.
The 3944 also provides a self-test diagnostics upon power-up of its internal
memory to insure the unit is operating properly. If a failure occurs,
the display will indicate which ROM or RAM has failed.
| GPIB Programmable Tunable
Active Filters Model 3945 |
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3Hz to 25.6MHz
Three Channel High-Pass/Low-Pass/Band-Pass/Band-Reject
Butterworth/Bessel Filter
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DESCRIPTION
The Krohn-Hite Model 3945 programmable filter provides one Butterworth
channel of low-pass, tunable over the range from 170Hz to 25.6MHz; and
two independent Butterworth or Bessel channels of low-pass, high-pass
or bypass, one channel of band-pass or band-reject, tunable over the range
from 3Hz to 2MHz.
The 3945 has been specifically designed for applications requiring high
frequency band-pass filtering. The high cutoff may be set to any frequency
between 170Hz and 10MHz, and the lower cutoff to any frequency between
3Hz and 2MHz.
50MHz LOW-NOISE AMPLIFIER
One channel of the 3945 can operate as a low-noise amplifier, bypassing
the filter, delivering a bandwidth of 50MHz and gains up to 46dB. This
is useful to users wanting to increase the gain of the signal and improve
signal-to-noise ratio before filtering. The other two channels of the
3945 furnish Bessel or Butterworth transfer functions and can be programmed
to operate as two low-pass, high-pass, one band-pass or band-reject filter
with gains to 40dB per channel.
NON-VOLATILE MEMORY
The 3945 offers 99 groups of non-volatile memory for storage of front
panel set-ups, which are stored in battery-backed CMOS. Set-ups can be
recalled with a simple command. Self-test diagnostics occur upon power-up
insuring that all internal memory is operating properly. If a failure
occurs, the display will indicate which ROM or RAM has failed.
| GPIB Programmable Tunable
Active Filters Model 3955 |
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170Hz to 25.6MHz
Dual Channel Low-Pass Butterworth or Bessel Filter
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DESCRIPTION
The Krohn-Hite Model 3955 programmable, dual channel, low-pass filter
is the first dual low-pass programmable filter of its kind, covering the
wide cutoff frequency range from 170Hz to 25.6MHz with 2 digits of resolution.
The 3955 is a 4-pole, maximally flat (Butterworth) filter, with an attenuation
slope of 24dB/octave and a stopband attenuation of >100dB referred
to 1Vrms input. The filter has selectable ac or dc coupling and selectable
1M or 50 ohm input impedance. Programmable input gains to 20dB and output
gains to 26dB are standard.
AMPLIFIER MODE
The Model 3955 also has the capability to be configured in an "amplifier
bypass" mode to operate as an amplifier, bypassing the filter. This
gives the user the ability to amplify without filtering when so desired.
| GPIB Programmable Tunable
Active Filters Model 3988 |
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0.03Hz to 1MHz
Two Channel High-Pass/Low-Pass/Band-Pass/Band-Reject
Butterworth/Bessel Filter
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DESCRIPTION
The Krohn-Hite Model 3988 Butterworth/Bessel dual channel filter is one
of a family of filters carefully designed with the user in mind, providing
ease of operation, reliability and price competitiveness.
The 3988 provides a tunable frequency range from 0.03Hz to 1MHz in the
low-pass mode and 0.03Hz to 300kHz in the high-pass mode. Both modes are
extended down to 0.003Hz with the 002 option. The frequency response characteristic
is either maximally flat (Butterworth) for clean filtering in the frequency
domain, or linear phase (Bessel) to provide superior pulse filtering.
Each channel of the 3988 is an 8-pole, wide range, low-pass/high-pass
filter or an amplifier providing gains to 70dB in 0.1dB steps. The 3988
will accept input signals of æ10V peak at 0dB gain and has selectable
ac or dc coupling. Overload detectors are standard and assist the user
in detecting input signals or incorrect gain settings. Ninety-nine groups
of non-volatile memory for storage of front panel set-ups are stored in
battery-backed CMOS which can be recalled with a simple command.
BAND-PASS/BAND-REJECT OPERATION
With the Model 3988, the user can simply connect two channels in series
to achieve band-pass operation or two in summed parallel for band-reject
operation.
Manual/Remote Controlled Multichannel Systems 1 to 32 Channels:
| GPIB Programmable Tunable
Active Filter Systems Model 3905B Model 3916B |
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5 and 16 Slot Chassis
Filter/Amplifier Mainframe Chassis
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DESCRIPTION
The Models 3905B and 3916B are Programmable Multichannel Filter Systems
which can be configured with many types of filter cards; Elliptical filters
for anti-aliasing, Butterworth filters for clean filtering in the frequency
domain, and Bessel filters which provide superior or pulse or complex
signal filtering. Filter cards that provide selectable frequency cutoffs
as low as 0.01Hz and as high as 25.6MHz with rolloff rates of 24dB to
115dB/octave make each System unique to any application. The System concept
was designed with the user in mind, providing ease of operation, flexibility
and performance.
SYSTEM CONFIGURATIONS
Two mainframes are available, the Model 3905B and the Model 3916B. The
3905B accommodates up to 5 plug-in filter cards in only 3" of rack
spacing. Both front and rear panel input and output BNC connectors are
standard, permitting convenient bench top or rack mounting use. The 3916B
accommodates up to 16 plug-in filter cards for the larger system user;
and used with the Model 34 filter card will give the user a maximum of
32 channels of filtering in one mainframe. Changing or adding cards to
either mainframe is accomplished with no modifications to the System.
Each mainframe incorporates an GPIB interface, for remote programming,
power supply, microprocessor, front panel keyboard, displays and indicators.
Extra large, independent keyboard, displays and indicators. Extra large,
independent displays are provided for input and output gain, cutoff frequency,
channel selection and overload detection. These independent displays present
all the most pertinent information simultaneously for maximum operator
convenience.
Plug-In Filter/Amplifier Cards:
| (GPIB) Programmable
Tunable Active Filter Systems Model 30A |
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1Hz to 99kHz
Elliptical Low-Pass Filter/Amplifier
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DESCRIPTION
The Model 30A Series low-pass, elliptical filter/voltage gain amplifier
is one of many plug-in filter cards used in the Models 3905B/3916B Programmable
Filter Systems chassis.
FILTER FEATURES
As an elliptical filter, the Model 30A Series has a tunable cutoff frequency
range from 0.01Hz to 99kHz, a rolloff rate of 115dB/octave and a minimum
stopband attenuation of >80dB. Passband ripple is typically 0.22dB.
The 30A provides either a single-ended or differential input with a common
mode rejection of >60dB. Input gains up to 40dB in 10dB steps and output
gains to 20dB are also provided. The 30A will accept input signals of
±10V peak at 0dB gain and has selectable ac or dc coupling. Overload
detectors are standard and assist the user in detecting excessive input
signals or incorrect gain settings.
| (GPIB) Programmable
Tunable Active Filter Systems Model 31A |
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1Hz to 99kHz
Elliptical Filter - Two Channel High-Pass/Low-Pass
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DESCRIPTION
The Model 31A Series high-pass, elliptical filter/voltage gain amplifier
is one of many plug-in filter cards used in the Models 3905B/3916B Programmable
Filter Systems chassis.
FILTER FEATURES
As an elliptical filter, the Model 31A Series has a tunable cutoff frequency
range from 0.01Hz to 99kHz, a rolloff rate of 115dB/octave and a minimum
stopband attenuation of >80dB. Passband ripple is typically 0.22dB.
The 31A provides either a single-ended or differential input with a common
mode rejection of >60dB. Input gains up to 40dB in 10dB steps and output
gains to 20dB are also provided. The 31A will accept input signals of
±10V peak at 0dB gain and has selectable ac or dc coupling. Overload
detectors are standard and assist the user in detecting excessive input
signals or incorrect gain settings.
| (GPIB) Programmable
Tunable Active Filter Systems Model 34A |
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3Hz to 2MHz, Dual Channel
Butterworth/Bessel (24dB/Octave)
Low-Pass/High-Pass/Band-Pass/Band-Reject Filter/Amplifier
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DESCRIPTION
The Model 34A dual channel, Butterworth/Bessel, plug-in filter card is
one of a family of filter cards used in Krohn-Hite Programmable Filter
System Mainframe Chassis. It was carefully designed with the user in mind,
providing ease of operation, reliability and price competitiveness
FEATURES
The 34A provides a tunable cutoff frequency range from 3Hz to 2MHz, with
a frequency response characteristic of maximally flat (Butterworth) for
clean filtering in the frequency domain, or linear phase (Bessel) to provide
superior pulse or complex signal filtering. The passband gain is unity
(standard on all Krohn-Hite filters), and the attenuation slope is 24dB/octave
per channel.
The filter can be programmed to operate in the low-pass, high-pass, band-pass,
band-reject or by-pass modes; or the two channels can be externally interconnected
to achieve 48dB/octave high-pass or low-pass slopes. The 34A also offers
input and output gains of 0dB or 20dB.
MAINFRAME CHASSIS
The 34A is a plug-in filter card for two mainframe chassis; Models 3905B
and 3916B. The 3905B is a 3" high chassis, allowing up to 5 filter/amplifier
cards. The 3916B allows up to 16 cards. With the Model 34A, this allows
the user to configure either a 10 channel or 32 channel filter system.
All backed with the quality Krohn-Hite has provided in tunable active
filters since 1949.
| (GPIB) Programmable
Tunable Active Filter Systems Model 35 |
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170Hz to 25.6MHz
Butterworth(24dB/Octave) Low-Pass Filter/Amplifier
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DESCRIPTION
The Krohn-Hite Model 35 Tunable Active, Low-Pass Filter Card is the first
programmable filter of its kind to cover the wide frequency range of 170Hz
to 25.6MHz with 2 digits of resolution. The Model 35 is a 4-pole, maximally
flat (Butterworth) filter, with an attenuation slope of 24dB/octave and
a stopband attenuation of 100dB referred to 1Vrms input.
FEATURES
The filter card has selectable AC or DC coupling and selectable 1M or
50 ohm input impedance. Programmable input gains of up to 20dB and output
gains up to 26dB are standard.
The Model 35 also has the capability to be configured in an Amplifier
By-Pass mode to operate as an amplifier, by-passing the filter. This gives
the user the ability to amplify without filtering when so desired.
SYSTEM CAPABILITY
The Model 35 filter card is part of an ever expanding line of filter cards
used to create a filtering system when plugged into mainframes Model 3905B
(3 1/2" high which will accept up to 5 filter cards) and the Model
3916B (which will accept up to 16 filter cards).
| (GPIB) Programmable
Tunable Active Filter Systems Model 38 |
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0.03Hz to 1MHz
Butterworth/Bessel (48dB/Octave)
Low-Pass/High-Pass/Band-Pass/Band-Reject Filter/Amplifier
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DESCRIPTION
The Krohn-Hite Model 38 Butterworth/Bessel, plug-in filter card is one
of a family of filter cards used in Krohn-Hite Programmable Filter System
Mainframes. It is carefully designed with the user in mind, providing
ease of operation, reliability and price competitiveness.
The 38 provides a tunable frequency range from 0.03Hz to 1MHz in the low-pass
mode and 0.03Hz to 300kHz in the high-pass mode. Both modes are extended
down to 0.003Hz with the 002 option. The frequency response characteristic
is either maximally flat (Butterworth) for clean filtering in the frequency
domain, or linear phase (Bessel) to provide superior pulse or complex
filtering is operator selectable.
The 38 is an 8-pole, wide range, low-pass/high-pass filter or an amplifier
providing gains to 70dB in 0.1dB steps. The 38 will accept input signals
of ±10V peak at 0dB gain and has selectable ac or dc coupling.
Overload detectors are standard and assist the user in detecting input
signals or incorrect gain settings.
APPLICATIONS
Applications of the Model 38 are ultra-sound measurements, random noise
testing, sound recording, suppressing interference in audio communications
and related fields of medical, geological, geophysical, oceanographic,
military and many more.
MAINFRAMES
The 38 is a plug-in card for two mainframes; Models 3905B and 3916B. The
3905B is a 3" high chassis, allowing up to 5 filter/amplifier cards.
The 3916B allows up to 16 cards. All backed with the quality Krohn-Hite
has provided in tunable active filters since 1949.
Fixed Frequency Systems and Modules 1 to 128
Channels:
| 128 Channel Signal Conditioning
Filter/Amplifier System Model 39128 |
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1Hz to 100kHz - Butterworth/Bessel (6dB to 48dB/Octave)
Low-Pass, High-Pass, Band-Pass
Input and Output Gains From 1 to 100
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DESCRIPTION
The NEW Krohn-Hite Model 39128 Multichannel Filter/Signal Conditioning
System is a mainframe chassis that houses up to sixteen, 8-channel plug-in
filter/amplifier cards providing as many as 128 channels of cost effective
signal conditioning over the frequency range from 1Hz to 100kHz.
Each plug-in card can be a filter, an amplifier or a mix of filters with
gain or amplifiers. The individual channels of the Model 39128 can be
a low-pass, high-pass and band-pass filter with either Butterworth or
Bessel responses. The attenuation slope of each channel can also be specified
between 6dB to 48dB/octave, with cutoff frequencies in the range from
1Hz to 100kHz.
The flexibility of the design also allows for each channel to be a filter
with pre and post-filter gain from 1 to 100 in 1% increments. Input configurations
may also be differential or single-ended.
INPUT AND OUTPUT CONNECTIONS
The Model 39128 is provided with two options for input and output connections.
The first option uses thirty-two 25-pin D-connectors for all input and
output connections. A pair of connectors accommodates an eight channel
plug-in card (one for input and one for output).
The second option, uses two screwdown 12-position plugs for eight input
channels for a total of 32 input plugs, two for each plug-in card. The
output connections are made through four 64-pin DIN connectors (3 row
format). Each connector provides the outputs for four 8-channel cards
or 32 channels.
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Fixed Frequency Filter Modules
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DESCRIPTION
The NEW 3A, 3B and 3C Series of continuous-time fixed-frequency precision
active filter modules from Krohn-Hite provide filtering in a 1 to 8-pole
compact package, with the choice of cutoff frequencies selectable within
the frequency range from 1Hz to 600kHz.
Choose between Butterworth or Bessel responses, user-defined input and
output gain from 1 to 100 in 1% increments (0dB to 40dB). Functions of
low-pass, high-pass and band-pass. Each one factory tuned to a user-specified
cutoff frequency, number of poles, response, function, single-ended or
differential input gains and output gains.
APPLICATIONS
Applications include: anti-alias filtering, data acquisition systems,
aerospace (sonar and navigation), sound and vibration testing, medical
electronics, communication systems, real and compressed time data analysis,
noise elimination and signal reconstruction.
AVAILABLE FILTER MODULES
- 3A Package: 1 to 4-pole.
- 3B Package: 1 to 4-pole with input gain and output gain; 5 to 8-pole, with no gain.
- 3C Package: 1 to 8-pole, single-ended or differential with input gain
and/or output gain.