Contents

The following Help Topics are available:

Selection Screen:	General Functions:

Resonant Frequency Input 	Save Design File

Resonator Geometry Selection	Open Design File

Resonator Support Selection	Printing the Design

Resonator Material Selection	Changing Units

Cavity Selection

Cavity Configuration Screen:	Trans-Tech:

Calculated/Desired Frequency	About Trans-Tech

Resonator Part Number	Custom Services

Dielectric Resonator Parameters 	Other Trans-Tech Products

Dielectric Resonator Re-Selection 	Sales Offices

Auto Tune 	References and Application Notes

Coupling to Microstrip

Package Dimensions 	About CARD:

Substrate Parameters 	About Computer Aided Resonator Design

Dielectric Support Parameters

Tuning Screw Extension

For Help on Help, Press F1


Resonant Frequency Input

The first data required by CARD is the desired resonant frequency of the cavity.  The frequency can be entered as MHz or GHz, depending on your preference.  Typing a number in the entry box, then pressing the enter key or clicking on one of the selection buttons will display the proper units for the frequency entered.

The frequency units can be changed by selecting either MHz or GHz under the Units, then Frequency Menu


Resonator Geometry Selection

Trans-Tech offers both disc and cylinder dielectric resonator geometries.  To select the desired geometry, click on the picture/button of either the disc or cylinder, so that check mark appears.  As you change your selection, the number of dielectric materials may increase or decrease.  The disc is initially selected to give the greatest number of catalog possibilities.

If a catalog part is not available in the cylindrical geometry and the cylindrical geometry is desired, use the disc geometry at the selection screen, then create a custom part at the cavity configuration screen.  Entering a number greater than 0 in the dr  entry box will create a custom cylindrical part.


Resonator Support Selection

Trans-Tech offers assembly configurations for all of the cylindrical resonators.  If the cylindrical geometry is selected and the support button is selected, the assembly type catalog data will be used.  If the disc geometry is selected and the support button is selected, the program will select an appropriately sized support for the resonator required for the desired resonant frequency.

Cylindrical (solid) resonators will generally use cylindrical (solid) supports, but where disc geometry is chosen for the resonator for screw mounting, a matching hole may be specified for the support.  The influence of a hole in the support upon the calculated frequency is very minor.  However, the thermal expansion coefficient of the support can have a profound effect upon the circuit resonant frequency, particularly for small height (Ls) supports.  In the latter case, the choice of support material can substantially alter the effective temperature cofficient of resonant frequency.  For best stability of resonant frequency, attention must be given to the influence of the support as well as the tolerance on the resonators's temperature coefficient.  CARD may be used in an iterative fashion to estimate the effect on frequency of expansion of the support, by varying Dielectric Support Parameters .

Note that CARD that the support is on the surface of the substrate, although in practice better dimensional and thermal stability may be effected by bringing the support from the resonator completely to the mounting surface, e.g. through the substrate.  In this case, order the support length L= Ls + Lsub.  Analyze the effect upon frequency in CARD by entering the total length L (Ls + Lsub) as Lsub, then reduce the Dielectric Support Parameters  to zero.

The cylindrical supports with Ds > .138 in are made of Cordierite with the following specifications:

Material	Cordierite (Mg, Al, Silicate)

Dielectric Constant 	4.5

Dielectric Loss at 10 GHz	<0.0002

Temperature Coefficient of Dielectric Constant (τε') (ppm/°C)	100

Volume Resistivity (Ohm-cm) at 20 °C	10^14

Coefficient of Thermal Expansion (ppm/C) at 25 - 200 °C	2.4

Thermal Conductivity (cal/cm sec °C) at 25 °C	0.010

Water Absorption	<.01

The cylindrical supports with Ds < .138 in are made of Forsterite with the following specifications:

Material	Forsterite (Mg, Silicate)

Dielectric Constant 	6.3

Dielectric Loss at 10 GHz	<0.0002

Temperature Coefficient of Dielectric Constant (τε') (ppm/°C)	107

Volume Resistivity (Ohm-cm) at 20 °C	10^14

Coefficient of Thermal Expansion (ppm/C) at 25 - 200 °C	2.4

Thermal Conductivity (cal/cm sec °C) at 25 °C	0.009

Water Absorption	<.6


Resonator Material Selection

Several kinds of materials are available at different frequency bands.  CARD will show the materials that are useful at the desired frequency.  The approximate Unloaded Q, diameter (Dr), and length (Lr) of the dielectric resonator is shown to help select the appropriate material. To select the desired material, click on the picture/button of the desired material, so that check mark appears.

Click on the material series for more information:

4500 Series Temperature Stable Dielectric Resonators

8300 Series Temperature Stable Dielectric Resonators

8600 Series Temperature Stable Dielectric Resonators

8700 Series Temperature Stable Dielectric Resonators

8800 Series Temperature Stable Dielectric Resonators


4500 Series
4500 Series Temperature Stable Dielectric Resonators

Description

The 4500 Series is designed for frequency operation form 800 MHz to 13.5 GHz.  This series offers a reduced size while maintaining a higher Q along with temperature stability relative to materials in the 30- 40 Er range.

Material Characteristics

Dielectric Constant	44.7 - 36.5

Temperature Coefficient of Resonant Frequency (τf) (ppm/°C)	-6 to +6

Q (1/tan δ) Min. at 850 MHz	>26,000

Q (1/tan δ) Min. at 4300 MHz	>9,500

Coefficient of Thermal Expansion (ppm/°C) (20 - 200 °C)	6.5

Thermal Conductivity (cal/cm sec °C) at 25 °C	0.005

Density (g/cc)	4.95

Water Absorption (%)	<0.01

Composition	Zirconium Titanate Based

Color	Dark Brown


8300 Series
D8300 Dielectric Resonators for Base Station Applications

Description

Trans-Tech's patented D8300 material represents our best product for UHF cellular radio applications, and has the best Q, vs. cost trade-off for PCS/PCN applications near 1.9 GHz.  A wide variety of temperature coefficients are available.

Material Characteristics

Dielectric Constant	35.0 - 36.5

Temperature Coefficient of Resonant Frequency (τf) (ppm/°C)	-3 to +9

Q (1/tan δ) Min. at 850 MHz	>28,000

Q (1/tan δ) Min. at 4300 MHz	>9,500

Insulation Resistance (Volume Resistivity) (Ohm-cm) at 25 °C	10^13

Coefficient of Thermal Expansion (ppm/°C) (20 - 200 °C)	10

Thermal Conductivity (cal/cm sec °C) at 25 °C	0.0045

Density (g/cm)	>4.65

Water Absorption (%)	<0.01

Composition	Barium Titanate

Color	Rust


8600 Series
8600 Series Temperature Stable Dielectric Resonators

Description

The 8600 series is designed for frequency operation from 0.7 GHz to 3.6 GHz in applications, where size reduction is an essential design requirement.  This series offers a wide selection of temperature coefficients of resonant frequency for easier circuit compensation, a dielectric constant of 80 for dramatic miniaturization, and a Q of 3,000 at 3 GHz.

Material Characteristics

Dielectric Constant at 0.7 GHz	80.0

Temperature Coefficient of Resonant Frequency (τf) (ppm/°C)	+3 to +9

Q (1/tan δ) Min. at 3.0 GHz	>3,000

Insulation Resistance (Volume Resistivity) (Ohm-cm) at 25 °C	>10^12

Coefficient of Thermal Expansion (ppm/°C) (20 - 200 °C)	8.5

Thermal Conductivity (cal/cm sec °C) at 25°C	0.005

Specific Heat (cal/g °C)	0.13

Density (g/cm)	5.75

Water Absorption (%)	<0.01

Vickers Hardness No. (kg/mm)	700

Flexural Strength (psi)	11,000

Composition	Ba, Lanthanides, Ti-oxide

Color	Tan


8700 Series
8700 Series Temperature Stable Dielectric Resonators

Description

The 8700 series is designed for use from 5.5 GHz to 32 GHz and features excellent loss characteristics.  This series offers a wide selection of temperature coefficients of resonant frequency for easier circuit compensation and a Q greater than 10,000 at 10 GHz for high stability DRO designs up to millimeter wave frequencies.

Material Characteristics

Dielectric Constant	28.2 - 31.0

Temperature Coefficient of Resonant Frequency (τf) (ppm/°C)	0 to +4

Q (1/tan δ) Min. at 10.0 GHz	>10,000

Insulation Resistance (Volume Resistivity) (Ohm-cm) at 25 °C	>10^14

Coefficient of Thermal Expansion (ppm/°C) (20 - 200 °C)	10

Thermal Conductivity (cal/cm sec °C) at 25°C	0.006

Specific Heat (cal/g °C)	0.07

Density (g/cm)	7.6

Water Absorption (%)	<0.01

Vickers Hardness No. (kg/mm)	700

Flexural Strength (psi)	10,000

Composition	Ba, Zn, Ti-oxide (perovskite)

Color	Yellow


8800 Series
8800 Series Temperature Stable Dielectric Resonators

Description

The 8800 series is designed for operation from 2.9 GHz to 5.2 GHz.  Most importantly, this resonator series features a homogeneous composition and high Q performance with excellent process control for applications that require large sizes.

Material Characteristics

Dielectric Constant	36.6 - 38.6

Temperature Coefficient of Resonant Frequency (τf) (ppm/°C)	+4

Q (1/tan δ) Min. at 4.5 GHz	>6,000

Insulation Resistance (Volume Resistivity) (Ohm-cm) at 25 °C	>10^14

Coefficient of Thermal Expansion (ppm/°C) (20 - 200 °C)	9.2

Thermal Conductivity (cal/cm sec °C) at 25°C	0.005

Specific Heat (cal/g °C)	0.15

Density (g/cm)	4.5 - 4.7

Water Absorption (%)	<0.01

Vickers Hardness No. (kg/mm)	800

Flexural Strength (psi)	11,000

Composition	Barium titanium-oxide

Color	Cream


Cavity Selection

The final choice before moving to the cavity configuration screen is the cavity type.  Two types of cavity are available, which CARD uses to make a better choice of resonator from the catalog parts available.

The ideal cavity uses the following parameters:

Air cavity (εr=1) above and below resonator.

Diameter (Do) 3 times the resonator diameter (Dr).

Length (Lo) from the bottom of the resonator to the top of the cavity is 2 times the resonator length (Lr).

Length (thickness) of the substrate (Lsub) is equal to the length of the resonator (Lr).

The thin substrate cavity uses the following parameters:

Air cavity (εr=1) above the resonator and 99% alumina (εr=9.8) below.

Diameter (Do) 3 times the resonator diameter (Dr).

Length (Lo) from the bottom of the resonator to the top of the cavity is 2 times the resonator length (Lr).

Length (thickness) of the substrate (Lsub) is 0.050 inches.

These parameters can and should be edited at the cavity configuration screen to resemble, as close as possible, the actual cavity configuration.  If significant changes are made at the cavity configuration screen, the Re-Select DR button should be clicked to change to the closest catalog part with a resonant frequency lower than the desired resonant frequency.


Calculated/Desired Frequency

Desired Frequency:

The desired frequency is transferred from the selection screen in the frequency units selected.  The Auto Tune function uses the desired frequency as the goal for its tuning algorithms (Resonator Lapping, Tuning Screw Extension, or the optimum combination).  If the desired frequency is changed, a new resonator will be selected from the same material series.  If the desired frequency is not available in the current material series, CARD will return you to the selection screen to select the appropriate material, geometry, and support.  The cavity sizes, substrate, etc. will not change unless insufficient room is available for the newly selected dielectric resonator.

Calculated Frequency:

The calculated frequency is the predicted resonant frequency for the cavity configuration given by the user.  Any changes to any parameter will cause an update to the calculated frequency.  CARD calculates the resonant frequency using the variational method by D. Kajfez (c) 1986.  The accuracy of this method is typically better than 2%.


Resonator Part Number

The current dielectric resonator part number is displayed below the calculated resonant frequency on the cavity configuration screen.

The part number can be decoded as follows:

Example:  C8812-0975-439-162

C88	Cylinder geometry from 8800 series material.

12	Type of material based on temperature coefficient of resonant frequency (τf).

0975	Diameter of resonator (Dr) in mils.

439	Length of resonator (Lr) in mils.

162	Inner diameter of cylinder (dr) in mils.


Dielectric Resonator Parameters

CARD initially chooses the dielectric resonator parameters, which conform to the geometry and desired frequency selected.  The cavity designer may adjust any of the resonator parameters by selecting the appropriate parameter and typing the new value in the units (mm/in) selected.  Special considerations should be taken, however, to maintain a catalog part with minimal changes, to maintain the economy and speed of delivery the catalog parts offer.  Varying any of the resonator parameters, except lapping (reducing the length) of the resonator, creates a custom part.  Changing the resonator dimensions should be viewed as a last resort to tune the cavity resonant frequency after support length (Ls), tuning screw length (Lt), substrate length (Lsub) and resonator lapping (Lr).

Dielectric Resonator Diameter (Dr):

The diameter of the resonator is chosen from a list of standard catalog diameters for each material type in the units selected.  The ratio of Lr to Dr should be kept between 0.35 and 0.45.  Changing the diameter of the 4500, 8300, 8600, 8700, and 8800 series material creates a custom part.  Any parts made of 8300 series material below 1475 MHz or 4500 series material below 1350 is currently a custom order designated by the (C) after the part number.

Dielectric Resonator Length (Lr):

The length of the resonator is chosen from a list of standard catalog lengths for each material type in the units selected, so the cavity resonant frequency falls below the desired frequency.  Standard parts can be lapped (reduced in length) to increase their resonant frequency by using the Auto Tune function or by manually reducing the resonator length (Lr).  The ratio of Lr to Dr should be kept between 0.35 and 0.45.  Adding to the length of the standard catalog part creates a custom part.

Dielectric Resonator Inner Diameter (dr):

The inner diameter of the cylindrical resonator is chosen from a list of standard catalog diameters for each material type in the units selected.  The addition of a hole in the disc resonator has the effect of a small resonant frequency increase.  The ratio of dr to Dr should be less than 0.5.  Changing an inner diameter of a cylindrical resonator or adding an inner diameter to a disc resonator standard catalog part creates a custom part.

Dielectric Resonator Dielectric Constant (εr) and τf :

The dielectric constant of the resonator is determined by the formulation of the ceramic material.  Different temperature coefficients of resonant frequency (τf ) have varying dielectric constants.  Changing the τf has the effect of changing the dielectric constant of the material and therefore the cavity resonant frequency.


Dielectric Resonator Re-Selection

Whenever significant changes have been made to the cavity configuration, clicking the Re-Select DR button will search for the catalog resonator with a lower resonant frequency in the cavity than the desired frequency.  Only for the 8300 series material below 1475 MHz and the 4500 series material below 1325 MHz, CARD recalculates the diameter (Dr) and length (Lr) of the resonator to keep the ratio of Lr to Dr at the optimum number of 0.4.  The reselect function is automatically activated for any change in the desired frequency.


Auto Tune

The auto tune function uses the two methods of tuning (lapping and tuning screw) available to the designer after the cavity has been fully configured.

Lapping:

The auto tune function calculates the resonant frequency for the range of dielectric resonator lengths (Lr) from 0.35 Dr to 0.45 Dr, plotting the total tuning range from resonator lapping.  Lapping (reducing the dielectric resonator length Lr) the resonator is the best way to change the resonant frequency with respect to unloaded Q.  However, material cannot be added, only taken away.  For this reason, CARD always chooses a resonator, which has a resonant frequency below the desired frequency.

Tuning Screw:

The metal tuning screw is the only external means of frequency tuning the cavity available in CARD. The auto tune function calculates the resonant frequency for the range of tuning screw lengths (heights) from the top of the cavity to the top of the resonator, plotting the total tuning range from tuning screw extension.  Care should taken not to rely on the tuning screw for greater than 5% tuning range.  At the 5% maximum number, the cavity Q has typically dropped to 75% of its initial value.  A total of 20% tuning range is achievable, but at the expense of significantly reduced unloaded cavity Q.

Optimum Combination of Lapping and Tuning Screw:

This method of tuning combines resonator length reduction with minimal tuning screw deflection.  CARD uses the tuning ranges developed from lapping and extending the tuning screw to first lap the resonator to within the 5% tuning range, then adjusts the tuning screw to achieve the desired resonant frequency.  Using this method of tuning should give enough margin for material tolerances and errors in the calculations.


Coupling to Microstrip

CARD supports coupling a dielectric resonator to straight microstrip transmission line.  The coupling coefficient (β) is primarily controlled by the distance (D) of the center of the dielectric resonator to the center of the microstrip.

Coupling Parameters:

D:  The distance from the center of the microstrip to the center of the dielectric resonator.  All output parameters are plotted as a function of D.  Vary the distance to realize the desired coupling coefficient (β).

β:  The coupling coefficient is the ratio of the unloaded quality factor to the external quality factor (Qu/Qe) or [(Qu/Ql) - 1].  Also the coupling coefficient is the ratio of the reflected energy to the transmitted energy at resonance (S11O/S21O).

Q:  (1/tand) The quality factor is a figure of merit for assessing the performance or quality of a resonator.  The quality factor (Q) is a measure of energy loss or dissipation per cycle as compared to the energy stored in the fields inside the resonator.  Q factor is defined by:

Q = 2π (Max Energy Stored) / (Average Energy Dissipated per Cycle)

Qu:  The unloaded Q is obtained when only the incidental dissipation of the system elements is present.  Qu is defined by the following equation:

1/Qu = 1/Qc+1/Qd+1/Qr	where:

Qc = Q of cavity conductor

Qd = Q of dielectric material

Qr = Radiation Q factor

Ql:  The loaded Q is obtained when the system is coupled to an external device that dissipates energy.  Ql is defined by the following equation:

1/Ql = 1/Qu+1/Qe	where:

Qe = Q of external coupling to microstrip

S21:  The transmission coefficient at resonance for the given value of D.

S11:  The reflection coefficient at resonance for the given value of D.


Package Dimensions

The package dimensions are initially set by the cavity selection button pressed at the selection screen.  Enter your actual cavity dimensions in the units selected.  The calculated frequency will be updated as the values change.

Do:  The package diameter is set to 3 times the diameter of the dielectric resonator (Dr).  CARD does not use this parameter in any of the resonant frequency calculations, but is displayed as a guideline to the designer.  Reducing Do will have the effect of reducing the unloaded Q of the cavity and is not recommended.

Lo:  The package length is defined as the length from the bottom of the substrate to the bottom of the cavity cover.  Lo is initially set to 3 times the length of the dielectric resonator (Lr) for the least impact to the unloaded Q factor.  Lo should be set from the bottom of the tuning screw in its fully retracted position to the bottom of the substrate.


Substrate Parameters

The substrate parameters are initially set by the cavity selection button at the selection screen.  Enter your actual substrate length (thickness) in the Lsub text box in the units selected.  The calculated frequency will be updated as the values change.

Lsub:  The substrate length (thickness) is set to the length of the dielectric resonator (Lr) in the case of the ideal cavity and to 50 mils in the case of the thin substrate.  Keeping the combination of support length (Ls) and substrate length (Lsub) greater than Lr will keep the metal base of the cavity from negatively impacting the unloaded Q.

εsub:  The substrate dielectric constant is set to 1.0 for air in the case of the ideal cavity and to 9.8 for 99% alumina in the case of the thin substrate.  The designer can select a new substrate material by selecting the substrate type from the Type pull-down box.  The substrate dielectric constant will be automatically updated to correspond to the new substrate material.  If your substrate is not on the list or differs in dielectric constant from those on the list, simply enter substrate dielectric constant in the εsub text entry box.


Dielectric Support Parameters

The dielectric support parameters are initially set by support selection button at the selection screen.  Enter your actual support length (thickness) in the Ls text box in the units selected.  The calculated frequency will be updated as the values change.

Ds:  The support diameter is set to the standard catalog value associated with the assembly dielectric resonator configuration.  CARD does not use this parameter in any of the resonant frequency calculations, but is displayed as a guideline to the designer.  Reducing Ds will have the effect of reducing the effective dielectric constant below the resonator.

Ls:  The support length (thickness) is set to the standard catalog value associated with the assembly dielectric resonator configuration.  Keeping the combination of support length (Ls) and substrate length (Lsub) greater than Lr  will keep the metal base of the cavity from negatively impacting the unloaded Q.

The thermal expansion coefficient of the support can have a profound effect upon the circuit resonant frequency, particularly for small height Ls supports.  In the latter case, the choice of support material can substantially alter the effective temperature cofficient of resonant frequency.  For best stability of resonant frequency, attention must be given to the influence of the support as well as the tolerance on the resonators's temperature coefficient.  CARD may be used in an iterative fashion to estimate the effect on frequency of expansion of the support, by varying Ls.

εs:  The support dielectric constant is set to 4.5 for Cordierite or 6.3 for Forsterite.  The designer can select a new support material by entering a new dielectric constant.


Tuning Screw Extension

The tuning screw extension is the only external means of varying the resonant frequency of the cavity supported by CARD.  The screw is initially set to 0, which means fully retracted to the cover of the cavity.  If the Auto Tune function is used and the designer chooses to accept the Auto Tune recommendations, the tuning screw extension will be set automatically.  The tuning screw can be moved manually by either entering the desired tuning screw extension in the units selected or by using the slide bar.  It is recommended that you use the Auto Tune function to view the full tuning range of the tuning screw.  Also, any tuning greater than 5% of the resonant frequency will result in a significant reduction in the unloaded cavity Q (5% tuning = approx 75% of maximum unloaded Q).


Save Design File

CARD will save your current design, along with units settings, to a file with the extension [*.ttf].  To save a design, select the Save Design entry under the File menu at the Cavity Configuration Screen.  After selecting the appropriate disk and directory, type the name of the file and the ttf extension will be added automatically.  The design file contains the current status as written to a text file, which can be viewed by any text editor.  The file can be opened later using the Open Design menu pick also under the File menu.


Open Design File

CARD will restore a design saved using the Save Design menu pick under the File menu using the Open Design menu pick also under the File menu. Only files with the extension [*.ttf] should be used.  To open a design, select the Open Design menu pick under the File menu at the Cavity Configuration Screen.  After selecting the appropriate disk and directory, select the name of the file with the ttf extension corresponding to the desired cavity configuration.  The current status will be changed to stored cavity configuration.


Printing the Datasheet

To print a design, select the Print Datasheet menu pick under the File menu at the Cavity Configuration Screen.  A picture of the current cavity configuration will be sent to the current Windows printer.


Changing Units

Frequency Units (MHz/GHz):

To change the frequency unit, select the Frequency menu pick under the Units menu at the Resonator Selection or the Cavity Configuration Screen.  Choose either MHz or GHz from the list and all frequency displays will be converted using the new frequency unit.  A check mark next to the frequency unit shows the frequency unit currently in use.

Length Units (inches/mm):

To change the length unit, select the Length menu pick under the Units menu at the Resonator Selection or the Cavity Configuration Screen.  Choose either inches or mm from the list and all length displays will be converted using the new length unit.  A check mark next to the length unit shows the length unit currently in use.


About Trans-Tech
Trans-Tech

A Subsidiary of Alpha Industries

Introduction:

An established world leader in the technical ceramic industry, Trans-Tech's ceramic materials include GPS patch antennas, microwave ferrites, microwave garnets, and microwave dielectrics, as well as dielectric and coaxial resonator materials and filters.  Additional materials and services include technical ceramic powders and thick- and thin-film metallization.

Trans-Tech can provide large-scale, automated processing as well as custom work;  the Adamstown, Maryland facility can handle production runs from 10 pieces to 10 million with a state-of-the-art electronics measurements laboratory for rigorous quality assurance testing.

Trans-Tech's experience in microwave ceramics has led to an increasing number of requests for custom research and development services.  To accommodate these requests, as well as provide internal, in-process quality control, Trans-Tech offers a fully equipped engineering R&D lab.

Cornerstones of Our Success:  Process Control

Trans-Tech believes that the best way to assure consistency and reproducibility is to thoroughly understand and control the entire ceramic process.  From formulating and blending raw materials, through firing and finishing the final product, Trans-Tech controls quality by controlling the entire manufacturing process, including designing and building its own dies and kilns.

The manufacturing process includes:

Qualifying --> Blending --> Forming --> Firing --> Finishing --> Quality

Excellent Technology and Customer Service

Trans-Tech is a manufacturing company built on outstanding ceramic technology tailored to satisfy customer requirements.  Our materials have established a reputation for quality, reproducibility and unsurpassed performance.  Our experienced applications engineers and sales staff team work with customers to provide the highest quality solutions for the best value.

•	Diverse, highly-trained technical staff, including electrical engineers, physicists, chemists, and ceramists.

•	Advanced forming and firing techniques based on proprietary processes and equipment.

•	Control of the entire ceramic process.

•	Our Commitment:  100% Customer Satisfaction.

•	Timely delivery of quality products.

•	Partnerships in product development.

•	Largest selection of RF/Microwave materials in the industry.

•	World-wide sales network for direct customer contact.

Continuous Quality Improvement

•	TQM -- Total Quality Management is an on going effort with each employee accepting responsibility to continuously improve our products, processes, and procedures.

•	Training -- Trans-Tech continually invests in its people with on going training.

•	Active Quality Assurance Group that oversees the analyzing and resolving of manufacturing problems.

•	The industry's most demanding customers, among them Motorola, Ericsson, Allen Telecom, and Lucent Technologies, have found Trans-Tech's Quality Systems satisfy their high standards. They have included our products in their select vendor status and ship-to-stock programs.

Alpha/Trans-Tech -- Your Single Source

In 1981, Trans-Tech became a wholly owned subsidiary of Alpha Industries.  Based in Woburn, Massachusetts, Alpha produces an extensive selection of RF GaAs integrated Circuits; amplifiers, attenuators, mixers, directional couplers, and power dividers, and Semiconductor Discretes; chip capacitors, FET fixed pad attenuators, receiving diodes, and varactors.  Our combined world-wide sales network enables Trans-Tech to service customers worldwide.  As a team, we can provide a variety of solutions to the design engineer.

Total Product Solution

Antennas

Ceramic

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Attenuators

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Switches

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Space

Die

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MMIC

Packaged

Trans-Tech

A Subsidiary of Alpha Industries


Qualifying

Raw materials are carefully analyzed for purity, particle size and distribution, reactivity, density, chemical analysis, and microstructure, to ensure the quality of the incoming powders.


Blending

Raw materials are blended, presintered, milled, spray-dried, and screened to create an optimal particle size.


Forming

After adding a binder, pressure or heat is applied to form material into required shapes.


Firing

The kilns are microprocessor controlled to assure consistency of the finished product.


Finishing

The fired ceramic is diamond ground, polished or lapped according to customer specifications to guarantee precise dimensions and close tolerances.


Quality

On-line Inspection and Continuous Statistical Review enables Trans-Tech to identify and resolve problems at the source, thereby minimizing rework, controlling costs, and maintaining our commitment to superior quality.


Other Trans-Tech Products

In addition to Dielectric Resonators, Trans-Tech offers the following products:

(Click on name to see more information.)

Ceramic Bandpass Filters

Trans-Tech offers ceramic bandpass filters in the frequency range of 200 MHz to 2.5 GHz.  They exhibit definite advantages in comparison to other filter technologies -- Cavity, Discrete Component, Helical, Microstrip, and SAW.

Microwave Ferrites

Microwave Garnets

Microwave Dielectrics

Non-Microwave Ferrites

Technical Ceramic Powders

Advanced Technical Ceramics (ATC) consists of a multi-faceted production line ranging from abrasion-resistant and thermal barrier materials to new applications and new product development.Trans-Tech is a strong research, development, and manufacturing company with a proven ability for scale-up production of new products.

Each powder can be synthesized in a number of modifications, either by conventional synthesis and processing or by state-of-the-art chemical precursor techniques.  Powders are available as fully reacted, flowable materials suitable for thermal spray processing.  They can also be custom prepared in sinterable form or as submicron particulates  for fabrication of monolithic ceramics and composites.  Specialized chemistries and purity, phase and particle surface area can be obtained depending on the specific application.

These powders are useful for a variety of specialized techniques and applications ranging from custom powders for research to high quality materials for thermal spraying, E-Beam deposition, and processing of semiconductor or dielectric composites.

Trans-Tech

A Subsidiary of Alpha Industries


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Advanced Technology Marketing

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Chelmsford, MA 01824

Telephone:  (978) 458-0200

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FAX: (205) 883-9516

Serving Georgia and Eastern Tennessee:

Atlanta, GA

Telephone:  (404) 256-9640

FAX: (404) 256-1938

Serving Central and Southern Florida and Puerto Rico:

Longwood, FL

Telephone:  (407) 788-1155

FAX: (407) 788-1176

Serving North and South Carolina:

Raleigh, NC

Telephone:  (919) 787-0330

FAX: (919) 781-8431


Koebert Associates

Serving Delaware, Eastern Pennsylvania and Southern New Jersey:

Glenside, PA  19038

Telephone:  (215) 887-2310

FAX:  (215) 576-1329

Email: kobert@cyberix.com

Serving Northern Virginia, West Virginia and Western Maryland:

Jefferson, MD  21755

Telephone:  (301) 371-8578

FAX:  (301) 371-6915

Southern Virginia:

Carrboro, NC  27510

Telephone:  (919) 932-5366

FAX:  (919) 932-5856


Chas Group

Serving Indiana, Kentucky, Ohio,

Michigan, and Western Pennsylvania:

Fort Wayne, IN  46804

Telephone:  (219) 459-1971

FAX:  (219) 459-1972


Cain-Forlaw

Serving Illinois, and Wisconsin:

Palatine, IL 60067

Telephone:  (847) 202-9898

FAX: (847) 202-9896

E-mail: cainforlaw@aol.com

Serving Minnesota; North Dakota; South Dakota

Burnsville, MN 55337

Telephone:  (612) 882-4090

FAX: (612) 882-4088

Serving Kansas; Nebraska; Missouri; Iowa

Merriam, KS 66202

Telephone:  (913) 789-9896

FAX: (913) 789-9897

E-mail: cainforkc@aol.com


Phase Com

Serving Texas except El Paso (97543), Arkansas, and Oklahoma

Ft. Worth, TX 76126

Telephone:  (972) 664-0442

FAX:  (817) 249-4421


Y & O Associates

Serving Arizona and New Mexico; El Paso, TX

Phoenix, AZ  85044

Telephone:  (800) 515-1554

FAX:  (800) 515-1574


Cain-Pollock, Inc.

Serving Colorado and Utah:

Parker, CO  80134

Telephone:  (303) 805-2515

FAX: (303) 805-2514

Email: S.M.Pollock@worldnet.ATT.net


Sea-Port Technical Sales

Serving Oregon and Washington:

Redmond, WA  98053

Telephone:  (425) 391-6714

FAX:  (425) 391-6715


Y & O Associates

Serving Southern California:

Tustin, CA  92680

Telephone:  (714) 838-5114

FAX:  (714) 838-5321

E-Mail: contactus@yando.com


Cain-Sweet, Co.

USA Office for Cain-Sweet, Co.:

Bellevue, CA  98004

Telephone:  (425) 462-2118

FAX:  (425) 451-9418

Serving British Columbia:

Burnaby, B.C.  V3J 1R6

Telephone:  (604) 420-6511

FAX:  (604) 420-6511

Serving Alberta, Saskatchewan and Manitoba:

Calgary, Alberta  T2E 6K9

Telephone:  (403) 250-7288

FAX:  (403) 250-7289

Serving Winnepeg and Ontario:

Ottawa, Ontario  K2B 1A5

Telephone:  (613) 820-2606

FAX:  (613) 820-2709

Serving Quebec, New Brunswick, Nova Scotia and Newfoundland:

Dollards Des Ormeaux, QC  H9B 2N4

Telephone:  (514) 421-0848

FAX:  (514) 421-1324


Disman Bakner

Serving Northern California and Nevada:

Mountain View, CA 94043

Telephone: 650-969-3010

FAX: 650-969-5620

Website: www.dbsales.com


Microwave Ferrites

Magnesium Ferrites with Saturation Magnetization (4pMs) from 750 to 3000 Gauss.

Nickel Ferrites with Saturation Magnetization (4pMs) from 500 to 5000 Gauss.

Lithium Ferrites with Saturation Magnetization (4pMs) from 600 to 4800 Gauss.

Millimeter Wave Ferrites

Nickel-Aluminum Ferrites

Nickel-Zinc Ferrites

Magnesium-Aluminum Ferrites

Magnesium-Zinc Ferrites


Microwave Garnets

Yttrium-Iron Garnets

Yttrium-Aluminum-Iron Garnets

Yttrium-Gadolinium-Iron Garnets

Yttrium-Gadolinium-Aluminum-Iron Garnets

Calcium Vanadium


Microwave Dielectrics

Cordierite (er=4.5)

Fosterite (er=6.3)

Alumina (er=9.5)

Magnesium Titanate (er=13 to 16)

Barium Tetratitanate (er=38, 50)

Titania (er=100)

Nickel Aluminum Titanates (SMAT Series er=9 to 14)

Magnesium Calcium Titanates (MCT Series er=18 to 140)

Spinel Material (er=71, 78, 98, & 110)


Non-Microwave Ferrites

Lithium-Zinc and Nickel-Colbalt Ferrites for non-microwave latching applications.

Pressure-sintered Manganese-Zinc and Nickel-Zinc Ferrites for record head applications.

Manganese-Zinc high permeability ferrites for shielding applications


Technical Ceramic Powders

Lanthanide Chromites and Ferrites

Yttrium oxide

Zirconia Materials

Conductive Spinels

Magnesium Aluminate Spinel

Alumina-Chromia

Ferrite 50 (For Radiation Absorption)


References and Application Notes

For further information, call your Alpha/Trans-Tech sales representative for any of the following:

(Click name for more information)

Coaxial Line Elements

Voltage Controlled Oscillator (VCO)

DR Coupling

Dielectric Resonator Oscillator

DR Q-Factor

Filters

General/Miscellaneous


About Computer Aided Resonator Design

Computer Aided Resonator Design was developed for Trans-Tech by:

ScillaSoft Consulting

102 Holiday Court

Mount Laurel, NJ  08054

Phone/FAX: (609) 222-1279

Email: 	scillasoft@aol.com

Variational Method of Resonant Frequency Calculation by D. Kajfez, Dielectric Resonators.  Artech House, Inc.  1986.

Microstrip Coupling Model by Patrick Champagne, "Better Coupling Model of DR to Microstrip Ensures Repeatability,"Microwaves & RF, September 1987, pp 113-118.


Ceramic Bandpass Filters

Two Pole Filters:

Cellular/NMT900/E-AMPS

Frequencies (MHz):  836.5, 881.5, 902.5,947.5

Cordless Telephone

Frequencies (MHz):  886.0, 914.5, 931.0

Spread Spectrum

Frequencies (MHz):  915.0, 922.0, 926.5

GPS

Frequencies (MHz):  1227.0, 1575.0

Three Pole Filters:

Cellular/NMT900/E-AMPS

Frequencies (MHz):  836.5, 881.5, 902.5,947.5

Cordless Telephone

Frequencies (MHz):  886.0, 914.5, 931.0

Spread Spectrum

Frequencies (MHz):  915.0, 922.0, 926.5

GPS

Frequencies (MHz):  1227.0, 1575.0


Trans-Tech, Inc.

Serving Alaska, Hawaii, Idaho, Montana and Wyoming:

Adamstown, MD

Telephone:  (301) 695-9400

FAX:  (301) 695-7065


Electronic Development Sales Pty., Ltd

Serving Australia:

Australia

Telephone:  011-61-2-9418-6999

FAX:  011-61-2-9418-6550

E-Mail: esaus@ozemail.com.au


Tech Partner A/S

Serving Denmark:

Denmark

Telephone:  011-45-874-61600

FAX:  011-45-874-61616


Alpha Industries Ltd.

Serving England, Ireland, Scotland, and Wales:

England

Telephone:  011-44-1628-475562

FAX:  011-44-1628-474078


Millimondes

Serving France and Belgium:

France

Telephone:  011-33-1-45-37-12-30

FAX:  011-33-1-46-32-81-06

E-Mail:  millimondes@wanadoo.fr


Integrated Electronics Oy Ab

Serving Finland and Russia:

Finland

Telephone:  011-358-9-586-1770

FAX:  011-358-586-1771

E-Mail: info@ieoy.fi


Alpha Industries GmbH
Municom

Serving Germany, Austria, Yugoslavia, Switzerland, and Eastern Europe:

Germany

Telephone:  011-49-8641-9585-0

FAX:  011-49-8641-3039

E-Mail: municom@dcinet.de


Kostas Karayannis S.A.

Serving Greece:

Greece

Telephone:  011-301-68-00-4601

FAX:  011-301-68-53-522


Semi Dice International BV

Serving The Netherlands, Luxembourg and Vlamish Belgium:

The Netherlands

Telephone:  011-31-075-6476968

FAX:  011-31-075-6408795


Aarjay International Pvt Ltd.

Serving India:

India

Telephone:  (91) 80-5262874

FAX: (91) 80-5274616

Elkay International, Inc.

Serving USA India:

Succasunna, NJ  07876

Telephone:  (973) 927-8647

FAX:  (973) 927-5370


Ormic Components, Inc.

Serving Israel:

Israel

Telephone:  011-972-3-649118

FAX:  011-972-3-6471942


Microelit S.P.A.

Serving Italy:

Milan, Italy

Telephone:  011-39-2-481-7900

FAX:  011-39-2-481-3594

E-Mail: microeli@mbox.vol.it

Rome, Italy

Telephone:  011-39-6-86894323

FAX:  011-39-6-8275270

E-Mail:  microeli@mbox.vol.it


M-RF Co., Ltd.

Serving Japan:

Tokyo, Japan

Telephone:  011-81-3-5821-3623

FAX:  011-81-3-5821-3625

E-Mail:  mrftokyo@2.mbn.or.jp

Osaka, Japan

Telephone:  011-81-6-313-7180

FAX:  011-81-6-313-7182

E-Mail:  mrfosaka@az.mbn.or.jp


S-Tec International Co. Ltd.

Serving Korea:

Korea

Telephone:  011-82-2-784-9898

FAX:  011-82-2-784-8600

E-Mail:  stec@kotis.net


DATA MATIK A/S

Serving Norway:

Norway

Telephone:  011-47-22-301730

FAX:  011-47-22-300273

E-mail: datamatik@sn.no


Vermont Representatives Commercial S/C Ltda

Serving Brazil:

Brazil

Telephone:  011-55-11-846-7372

FAX:  011-55-11-846-0308

E-Mail:  vermont@sanet.com.br


Iberica de Componentes, S.A.

Serving Spain:

Spain

Telephone:  011-34-919-2970

FAX:  011-34-1-6531019

E-Mail:  ibercom2@mad.servicom.es


Compomill AB
Nordimar

Serving Sweden:

Sweden

Telephone:  011-46-8-753-3760

FAX:  011-46-8-622-6304


Ameleks Corp.

Serving Taiwan:

Taiwan

Telephone:  011-886-2-2758-6958

FAX:  011-886-2-2758-6987

E-Mail: ameleks@ms9.hinet.net


Pangaea (HK) Limited

Serving Hong Kong and People's Republic of China:

Hong Kong

Telephone:  011-852-2836-3301

FAX:  011-852-2834-7340

email: panagaea@wlink.net


Pangaea Corporation Philippines
Pangaea Corporation

Serving Philippines:

Philippines

Telephone:  011-632-810-5809

Fax: 011-632-818-0603

E-Mail: pangaea@compass.com.ph

USA Office for Pangaea:

Littleton, MA  01460

Telephone:  (508) 486-0942

FAX:  (508) 486-4647

E-Mail:  pangaeaus@internetMCI.com

S&T Enterprises

Serving Singapore:

Singapore

Telephone: 011-65-745-8910

FAX: 011-65-741-8200


Eltronik Incorporated

Serving Turkey:

North Bergen, NJ  07047

Telephone: (201) 453-0401

FAX: (201) 453-0959

Eltronik Elektronik Sanayli Ve Ticaret Ltd. Sti

Serving Turkey:

Turkey

Telephone:  011-90-312-467-9952

FAX:  011-90-312-467-9828


Components & Instruments, Ltd.

Serving New Zealand:

Telephone:  011-644-237-5632

FAX:  011-644-237-8392


Simm Electronics

Serving South Africa:

South Africa

Telephone:  011-27-11-802-7808

FAX:  011-27-11-802-7875

E-Mail:  pengel@cis.co.za


Mexitek, S.A.

Serving Mexico:

Mexico

Telephone:  011-525-575-0269

FAX:  011-525-575-9981

E-mail: 74173.757@compuserve.com


US Sales Offices

Click on the area of interest in the United States for contact information:


European Sales Offices

Click on the area of interest in Europe for contact information:


Asian and Australian Sales Offices

Click on the area of interest in Asia for contact information:


Custom Services

Ulimately the designer may require more precise frequency control and may wish Trans-Tech to size the resonator(s) to a specified frequency.  We typically adjust the height (Lr) in this case to accomodate variations in dielectric constant and minor dimensional differences.  Trans-Tech establishes a correlation between in-circuit performance (measured by designer) and resonance of the same part as determined in our precision reference cavities.


Coaxial Line Elements

Trans-Tech Application Notes:

1009	Computer Simulation of Coaxial Resonators

1010	Frequency Tuning Coaxial Resonators

1014	The Characteristic Impedance of Coaxial Resonators

1015	Measuring SRF and Q of Coaxial Resonators

Selected Articles and Books:

T. Moreno, "Microwave Transmission Design Data," ARTECH House, ISBN 089-006-346-X

G. Matthaei, L. Young, and E. Jones, "Microwave Filters, Impedance-Matching Networks, and Coupling Structures, "ARTECH House, ISBN 089-006-099-1.

K. Hano and K. Sawamoto, "A Bandpass Filter Using Direct-Coupled Quarter-Wavelength Coaxial Dielectric Resonators," Microwave Journal, November 1987, pp. 141-160.


Voltage Controlled Oscillator (VCO) References

Trans-Tech Application Notes:

1008	Coaxial Resonators for VCO Applications

1017	The Influence of Coaxial Inductors on VCO Tuning Bandwidth

1021	Empirically Determining the VCO Inductor

Selected Articles and Books:

D. Rosemarin, "Design improves linearity of PLL synthesizers, "Microwaves & RF, December 1991. [includes VCO calculations for tuning range]

B. Kelly, N. Evans, and B. Burns, "1.8 Ghz direct frequency VCO with ACD assessment, " RF Design, February 1993, pp.29-38.

U. Rhode, "Oscillator design for lowest phase noise, " Microwave Engineering Europe, May 1994, pp. 31-40. [900 Mhz example]

U. Rhode and S. Joshi, "Compact PLLs cut current in portable systems, " Microwaves & RF, July 1995, pp. 115-120.

D. Polidi, "Design method for a coaxial-resonator oscillator," RF Design, October 1995, pp. 66-68. [2.3 Ghz example]

U. Rhode, "Digital PLL frequency synthesizers - theory and design, " Prentice-Hall, Englewood Cliffs, NJ, 1983.

W. Hayward, "Introduction to radio frequency design, " ARRL, 1994, ISBN 0-87259-492-0.

R. Rhea, "Oscillator design and computer simulation, " Noble Publishing, 1995, ISBN 1-884932-30-4.

"A comparison of microstrip & coaxial resonator voltage controlled oscillator design approaches, " Synergy Microwave Corporation (Paterson, NJ) 1996 Supplementary Catalog.


DR Coupling References

Selected Articles and Books:

R. Boneti, A. Atia, "Analysis of Microstrip Circuits Coupled to Dielectric Resonators, " IEEE Trans. Microwave Theory Tech., Vol. MTT-29, No. 12, December 1981, pp. 1333-1337. [single curved microstrip line]

J. Brand and J. Ronnau, "Practical Determination of Dielectric Resonator Coupling Coefficients, " Microwave Journal, November 1986, pp. 141-144.  [Empirical image technique for finding coupling coefficients]

P. Champagne, "Better Coupling Model of DR to Microstrip Insures Repeatability,"Microwaves & RF, September 1987, pp. 113-118. [coupling to single line]


Dielectric Resonator Oscillator Reference

Trans-Tech Application Notes:

1030	Optimize DRO's for Low Phase Noise

Selected Articles and Books:

J. Walworth, "Theory of operation of the DRO," RF Design, January 1985, pp. 26-31.[coupling to one or two lines, equivalent circuits, empirical determination of coupling]

K. Agarwal, "Applications of GaAs Heterojunction Bipolar Transistor in Microwave Dielectric Resonator Oscillators, " Microwave Journal, November 1986, pp. 177-182. [phase noise comparison]

U. Rhode, "Designing a Low Noise Oscillator Using CAD Tools, " Microwave Journal, December 1986, pp. 140-144. [Noise reduction by locking 13 Ghz DRO. Example of author's CAD program]

R. Jaques, "Paving the way for stabilized DR oscillators," Microwaves & RF, September 1987, pp.103-108. [temperature drift analysis]

A. Murphy and P. Murphy, "Computer Program Aids Dielectric Resonator Feedback Oscillator Design," Microwave Journal, September 1988, pp.131-148. [FORTRAN, feedback configuration]

A.P.S. Khanna, "A Highly-Stable 36 Ghz GaAs FET DRO with Phase-Lock Capability,"Microwave Journal, July 1989, pp.117-122.

A.P.S. Khanna, "Understand DRO design methods and operation," Microwaves & RF, April 1992, pp.120-124. [Fundamentals, operating principles, dielectric material choices]

A.P.S. Khanna, "Picking devices for optimum DRO performance,"Microwaves & RF, May 1992, pp.179-182. [Active devices and various circuit topologies]

H. Ashoka, "Directly-modulated DRO drives S-band video links,"Microwaves & RF, June 1992, pp.89-90. [Varactor coupled to DR, 20 Mhz tuning at 3.45 GHz]

A.P.S. Khanna, "Design a wide range of quiet DRO circuits,"Microwaves & RF, July 1992, pp.95-98. [Various circuit configurations]

J. Floch, "Technique allows simple design of microwave DROs,"Microwaves & RF, March 1995, pp.107-112. [Series feedback example near 10 GHz]


DR Q-Factor Reference

Selected Articles and Books:

A. Podcameni et al, "Unloaded quality factor measurement for MIC dielectric resonator applications,"Electronic Letters, 3rd September 1981, Vol. 17, No. 18, pp. 656-657. [network analyzer measurement of DR's coupled to 50-ohm microstrip]

A.P.S. Khanna, "Q Measurement of microstrip-coupled dielectric resonators,"Microwaves & RF, January 1984, pp. 81-86. [equivalent circuit, network analyzer measurement of DR's coupled to 50-ohm microstrip]


Filter References

Trans-Tech Application Notes:

1012	A Notch Filter Using A Coaxial Resonator

1013	A Bandpass Filter Using A Coaxial Resonator

1016	A Ceramic Waveguide Highpass Filter

Selected Articles and Books:

S. Cohn, "Microwave Bandpass Filters Containing High-Q Dielectric Resonators, " IEEE Trans. Microwave Theory Tech., Vol. MTT-16, No. 4 April 1968, pp. 218-227. [experimental coupling coefficents and simplified formula for DR's in waveguide]

A. Podcameni et al, "Design of microwave oscillators and filters using transmission-mode dielectric resonators coupled to microstrip lines, " IEEE Trans. Microwave Theory Tech., Vol. MTT-33, No. 12, December 1985, pp. 1329-1332. [equivalent circuit for transmission-mode, coupling to two lines]


General/Miscellaneous References

Selected Articles and Books:

Courtney, W.E., "Analysis and evaluation of a method of measuring the complex permittivity and permeability of microwave insulators, " IEEE Trans. Microwave Theory Tech., Vol. MTT-18, pp. 476-485, August 1970. [descriptiion of the Courtney test fixture for Er measurement]

T. Higashi and T. Makino, "Resonant frequency stability of the dielectric resonator on a dielectric resonator on a dielectric substrate," IEEE Trans. Microwave Theory Tech., Vol. MTT-29, pp. 1048-1052, October 1981. [approximate formulas, temperature stability on substrate]

D. Kajfez, P. Guillon, "Dielectric Resonators,"ARTECH House 1986, ISBN 0-89006-201-3

D. Kajfez, "PC Program evaluates higher-order modes in shielded dielectric resonators," Microwave Journal, May 1988, pp. 345-355. [Introduction to FOAM program]

R. Mongia, "Easy resonant frequency computations for ring resonators," Microwave Journal, November 1992, pp. 105-108. [effects of center axial hole on frequency].

N. Klein et al, "Properties and applications of HTS-shielded dielectric resonators: state-of-the-art report," IEEE Trans. Microwave Theory Tech., Vol. MTT-44, No. 7, July 1996, pp. 1369-1373. [results of superconducting experiments]