RF/Microwave Filters
Trilithic manufactures a complete line of fixed frequency filter products including Bandpass, Lowpass, Highpass and Bandreject. These filters are available in a wide variety of formats including Surface Mount, PC Mount, Coaxial, Cavity and Tunable.
Trilithic's capabilities are a fusion of engineering and design capabilities of Trilithic and two of the most senior filter companies in the world, CIR-Q-TEL and Texscan Instruments Division. The CIR-Q-TEL and Texscan portions of our company have been custom designing and manufacturing filters continuously since the early 1960's.
The following fixed filter products outline our capabilities and standard packaging formats. In addition to the products and design guidelines shown, we are usually able to solve unique technical problems not covered in this catalog.
Filters - Fixed Frequency
Tunable Filters
Other Filters
Trilithic Cavity Bandpass Filters exhibit lower losses and narrower bandwidths than most coaxial filters.
The series CH and CR filters cover a frequency range from 30 MHz to 3,000 MHz. Percent 3 dB bandwidth ranges from 0.2% to 3%. The CR series uses 1 /4 wavelength resonant structures while the CH series uses a helical coil design to achieve lower frequency operation.
Units are available with two through six sections providing a Chebyshev response with low insertion loss. VSWR is less than 1.5:1. Each unit is housed in a high "Q" sturdy aluminum case. Cavities are iris coupled and shielded to minimize RF leakage.
| CH - Filters |  |
Helical Cavity | 30 to 400 MHz | 0.2% to 3% | See Page 50 | Large | Very Low |
| CR - Filters |  |
1 /4 Wave Cavity | 400 to 3,000 MHz | 0.2% to 3% | See Page 50 | Large | Very Low |
Download Cavity Filter Catalog Pages
The combline style of filter offers the systems designer an extremely low insertion loss filter in the medium to wide bandwidth ranges. Typical losses are less than 1 dB for most designs with bandwidths of 5% or more.
| CC - Filters |  |
1 /4 Wave Cavity | 300 to 18,000 MHz | 0.2% to 60% | See Page 52 | Small to Large | Very Low |
Download - Combline Cavity Filter Catalog Pages
Trilithic Tubular Bandpass Filters are a low ripple Chebyshev design and are available with 2 thru 12 sections in frequency ranges from 25 to 6,000 MHz with relative band-widths from 2% to 50%.
Six different sizes and frequency ranges allow for the selection of an optimal design for each requirement. Almost any type of input or output connection is available as a standard item.
BE Series
1 1/4 " Diameter
Mounting hardware available. See Mounting Options.
| Specifications | Standard | Special |
|---|---|---|
|
Electrical |
||
| Center Frequency MHz | 40 to 600 | 25 to 1,000 |
| Number of Sections | 3 to 8 | 9 to 12 |
| Nominal Impedance | 50 Ohms | 50/75 Ohms |
| Maximum VSWR | 1.5:1 | 1.2:1 |
| Percent 3 dB BW | 3-40% | 1-70% |
| Maximum Input Power (Average Watts to 10,000 ft.) | See (1) Below | See (1) Below |
| Maximum Input Power (Peak Watts to 10,000 ft.) | See (1) Below | See (1) Below |
| Environmental | ||
| Shock | 15 G's | 75 G's |
| Vibration | 5 G's | 30 G's |
| Relative Humidity | 90% | 100% |
| Altitude | Unlimited | Unlimited |
| Operating Temperature | -20 to 50 C | -55 to 125 C |
| Non-operating Temperature | -54 to 70 C | -55 to 150 C |
| Mechanical | ||
| Approximate Weight | 1.5 Oz./ln. | 1.5 Oz./ln. |
(1) Dependent upon center frequency and percent bandwidth. Please consult factory for rated power.
Download Tubular/Coaxial Filter Catalog Pages
BD Series
3/4" Diameter
Mounting hardware available. See Mounting Options.
| Specifications | Standard | Special |
|---|---|---|
|
Electrical |
||
| Center Frequency MHz | 80 to 1,000 | 40 to 1,700 |
| Number of Sections | 3 to 8 | 9 to 12 |
| Nominal Impedance | 50 Ohms | 50/75 Ohms |
| Maximum VSWR | 1.5:1 | 1.2:1 |
| Percent 3 dB BW | 3-40% | 1-70% |
| Maximum Input Power (Average Watts to 10,000 ft.) | See (1) Below | See (1) Below |
| Maximum Input Power (Peak Watts to 10,000 ft.) | See (1) Below | See (1) Below |
| Environmental | ||
| Shock | 15 G's | 75 G's |
| Vibration | 5 G's | 30 G's |
| Relative Humidity | 90% | 100% |
| Altitude | Unlimited | Unlimited |
| Operating Temperature | -20 to 50 C | -55 to 125 C |
| Non-operating Temperature | -54 to 70 C | -55 to 150 C |
| Mechanical | ||
| Approximate Weight | 1 Oz./ln. | 1 Oz./ln. |
(1) Dependent upon center frequency and percent bandwidth. Please consult factory for rated power.
Download Tubular/Coaxial Filter Catalog Pages
BC Series
1/2" Diameter
Mounting hardware available. See Mounting Options.
| Specifications | Standard | Special |
|---|---|---|
|
Electrical |
||
| Center Frequency MHz | 100 to 2,000 | 60 to 3,000 |
| Number of Sections | 3 to 8 | 9 to 12 |
| Nominal Impedance | 50 Ohms | 50/75 Ohms |
| Maximum VSWR | 1.5:1 | 1.2:1 |
| Percent 3 dB BW | 3-40% | 1-70% |
| Maximum Input Power (Average Watts to 10,000 ft.) | See (1) Below | See (1) Below |
| Maximum Input Power (Peak Watts to 10,000 ft.) | See (1) Below | See (1) Below |
| Environmental | ||
| Shock | 15 G's | 75 G's |
| Vibration | 5 G's | 30 G's |
| Relative Humidity | 90% | 100% |
| Altitude | Unlimited | Unlimited |
| Operating Temperature | -20 to 50 C | -55 to 125 C |
| Non-operating Temperature | -54 to 70 C | -55 to 150 C |
| Mechanical | ||
| Approximate Weight | .75 Oz./ln. | .75 Oz./ln. |
(1) Dependent upon center frequency and percent bandwidth. Please consult factory for rated power.
Download Tubular/Coaxial Filter Catalog Pages
BBA Series
1/4" Diameter
Mounting hardware available. See Mounting Options.
| Specifications | Standard | Special |
|---|---|---|
|
Electrical |
||
| Center Frequency MHz | 400 to 4,000 | 200 to 6,000 |
| Number of Sections | 3 to 6 | 7 to 8 |
| Nominal Impedance | 50 Ohms | 50 Ohms |
| Maximum VSWR | 1.5:1 | 1.2:1 |
| Percent 3 dB BW | 3-40% | 1-70% |
| Maximum Input Power (Average Watts to 10,000 ft.) | See (1) Below | See (1) Below |
| Maximum Input Power (Peak Watts to 10,000 ft.) | See (1) Below | See (1) Below |
| Environmental | ||
| Shock | 15 G's | 75 G's |
| Vibration | 5 G's | 30 G's |
| Relative Humidity | 90% | 100% |
| Altitude | Unlimited | Unlimited |
| Operating Temperature | -20 to 50 C | -55 to 125 C |
| Non-operating Temperature | -54 to 70 C | -55 to 150 C |
| Mechanical | ||
| Approximate Weight | .375 Oz./ln. | .375 Oz./ln. |
(1) Dependent upon center frequency and percent bandwidth. Please consult factory for rated power.
Download Tubular/Coaxial Filter Catalog Pages
Click on the link above to go to the Ultraminature LC Filters page
Bandreject filters (or notches) are used to pass a large operating band of frequencies, while rejecting a narrow band of frequencies. This band of frequencies may have a 3 dB bandwidth as small as 0.5% or as large as 30 or 40%. The band reject filter is designed for each customer's specific frequency applications.
Trilithic provides bandreject filters in many configurations:
Lumped Component
Used for wider bandwidth notches - 10% to 30 or 40% - and for frequencies below 150 MHz.
Helical Resonator
Used for narrow bandwidth notches - 0.5% to 5% - and center frequencies of 30 to 400 MHz.
Coaxial Resonator
Used for narrow bandwidth applications - 0.5% to 5% - for center frequencies of 400 to 3,000 MHz.In each of these configurations, certain electrical performances may be modified or improved. These may include insertion loss, VSWR, power handling, and/or extended passbands.
The following outlines our capabilities and standard packaging formats. In addition to the products and design guidelines shown, we are usually able to solve unique technical problems not shown here.
| Series | Picture | Format | Frequency Range | Average Power | Relative Size | Relative Loss |
|---|---|---|---|---|---|---|
| Ultraminiature LC |  |
PC Mount or Coaxial Various Packages | 4 to 4,500 MHz | 1 Watt | Very Small | Medium to High |
| Standard LC |  |
PC Mount or Coaxial Various Packages | 0.1 to 200 MHz | to 50 Watts | Small to Medium | Medium |
| LE |  |
1 1/4" Dia. Coaxial | 20 to 1,000 MHz | to 700 Watts | Large | Very Low |
| LEA Non-standard |
 |
1 1/8" Dia. Coaxial | 40 to 2,000 MHz | to 700 Watts | Large | Very Low |
| LD |  |
3/4" Dia. Coaxial | 60 to 3,000 | to 100 Watts | Medium | Low |
| LC |  |
3/8" Dia. Coaxial | 100 to 4,000 MHz | to 50 Watts | Small | Medium |
| LB Non-standard |
 |
1/2" Dia. Coaxial | 30 to 400 MHz | to 20 Watts | Small | Medium |
| LBA |  |
1/4" Dia. Coaxial | 200 to 18,000 MHz | to 5 Watts | Very Small | Medium |
| LEC |  |
Very High Power Coaxial | 25 to 1,000 MHz | to 2.5 KW | Very Large | Very Low |
Download Lowpass & Highpass Filters Catalog Pages
Trilithic
VF Series tunable bandpass filters cover a frequency range from 3 MHz to 4,000
MHz with any single model covering an octave. Standard units are available with
either a three or five section response and have a 3 dB bandwidth of 5%
&plumn;1%* with low insertion loss values from 0.2 dB through 1.5 dB. VSWR
is less than 1.5:1. Each unit is housed in a sturdy aluminum case with high
"Q" cavities.
These cavities are iris coupled and shielded to minimize RF leakage. A constant filter response is maintained from the low end of the tuning cycle to the high end by varying the loaded capacitance of each section inversely as the frequency is increased. The tuning arm is coupled directly to the driving mechanism which incorporates a precision vernier with a 6:1 ratio. An engraved dial which is calibrated directly in frequency indicates the center frequency of each filter response with resettability to within 0.5%, thereby eliminating calibration charts or guesswork. With the excellent filtering characteristic of the VF bandpass series, they are ideally suited wherever precision laboratory measurements are required.
They are used for noise and harmonic reduction, diplexing and channel selection, and wherever a high level of attenuation is required below and above the signal band.
Height is approximately 3".
Download Tunable Bandpass Filter Catalog Pages
The VNF Series of tunable bandreject filters are available as high "Q", three section, tunable cavity filters. The series covers the frequency range of 25 MHz to 2,500 MHz. Each model is tunable over an octave bandwidth with notch depths of at least 45 dB. The units are tuned via a knob with a dial calibrated in MHz and accurate to 1%. Passband loss is typically less than 0.5 dB and passband VSWR is typically less than 1.2:1.
These filters can be used to eliminate undesired signals as close to the passband as 500 kHz for the low band unit and 3 to 8 MHz for the 500 to 1,000 MHz band. For special requirements not covered by these standard models, please contact the factory.
Download Tunable Bandreject Filter Catalog Pages
Trilithic offers the most comprehensive line of RF preselectors for broadband coaxial testing and production applications. For these requirements, the VF series is used as a bandpass preselector to eliminate intermodulation mixing caused by multiple carriers present on a broadband system. The medium selectivity VF-1 (55-440 MHz) and VF-3 (55-880 MHz) are designed for forward path only systems where economy is important and adjacent channel rejection is of less concern. The industry standard models VF-2 (55-440 MHz) and VF-4 (55-880 MHz) have high selectivity rejection for forward path only systems that are at or near channel capacity. The high selectivity VF-5 (7-880 MHz) is the only preselector of its type that combines both forward and return path preselection. Return path preselection below 55 MHz is accomplished with a set of six fixed channel filters. Channels T7 through T12 are standard and others are available upon request. The forward path uses the identical tunable filters built for the VF-4 model.
Features:
- Automated Forward and Return Preselection
- GPIB and Front Panel User Control
- Switchable T7 - T13 Channel Filters
- Tunable From 55 - 880 MHz
- High-Selectivity Shape Factor
- Integrated 20 dB Preamplifier
- Switchable Aux Signal Ports for Special Testing Requirements
The Trilithic DCVF-5 Automated Preselector Filter is designed for quick, accurate and repeatable measurements of key CATV system network performance specifications.
Based on the popular VF-5 Manual Preselector, the DCVF-5 offers automation capabilities of switching signal paths through the T7 - T13 fixed filters and tuning the 55 - 880 MHz variable filter bank under GPIB or Front Panel user control. Signal bypass and termination modes are provided as well as an integrated 20 dB preamplifier for quick and flexible testing configurations.
The advantage in using the Trilithic DCVF-5 Automated Preselector provides the preselection needed for the accurate measurement of composite triple beat, cross modulation and other spurious signals in a working CATV system.
The DCVF-5 preselector placed between a test instrument and the CATV system test point blocks all un-needed signals, passing only the carrier or spectrum to be analyzed to the instrument's input. By eliminating input overload, a DCVF-5 can improve an instrument's reliable measurement range as much as 30 dB. By using the GPIB control bus interface, the preselection filter is tuned concurrent with the test instrument significantly reducing the time to obtain data for complex measurements such as composite triple beat, cross modulation, and spurious signals.
The DCVF-5 Automated Preselector can also be used to extend the range and accuracy of fiber optic measurements. Composite second order and system noise tests require filters with the best possible selectivity and shape factors. The DCVF-5 filter banks easily meet these stringent requirements for testing modern CATV systems using fiber optic transport.
Custom filter arrangements for the DCVF-5 are also
available.
Call us for specialized testing requirements.
Download Automated Preselector Filter Catalog Pages
- Bandpass Coaxial Filter Design Considerations
- Lowpass Highpass Design Considerations
- Lowpass Coaxial Filter Design Considerations