521H Series | Low Power Handling
Mi-Wave’s 521 Series Fixed Waveguide Attenuators are precision RF components designed to provide accurate, repeatable fixed attenuation across standard waveguide bands from 8 GHz to 220 GHz. These attenuators are engineered for microwave and millimeter-wave applications where stable signal reduction and consistent performance are critical.
Available in standard attenuation values from 6 dB to 30 dB, each 521 Series attenuator is calibrated at the exact frequency specified at the time of order and provides accuracy within 0.1 dB or 1%, ensuring dependable performance in precision RF measurement environments.
All units are designed as H-plane fixed attenuators, making them well suited for integration into waveguide transmission lines where predictable attenuation and low reflection characteristics are required. The 521 Series is commonly used to isolate signal generators from mismatched load effects, extend the usable range of RF power measurement equipment, and provide controlled reduction of signal levels in microwave and millimeter-wave systems.
With robust mechanical construction and reliable electrical performance, the 521 Series offers a practical and dependable solution for engineers requiring fixed attenuation in laboratory, instrumentation, and system-level applications.
The standard models shown represent only part of Mi-Wave’s broader product capabilities. Custom configurations are available to support specific frequency bands, interfaces, and application requirements, enabling optimized solutions for specialized RF, microwave, and millimeter-wave systems.
Features & Specifications
Mi-Wave’s 521 Series Fixed Waveguide Attenuators are engineered to deliver stable, high-accuracy attenuation across microwave and millimeter-wave systems.
Frequency Coverage: 8 GHz to 220 GHz
Available across standard waveguide bands for use in microwave and mmWave applications.
Fixed Attenuation Values: 6 dB to 30 dB
Offered in standard attenuation values depending on waveguide size and application requirements.
High Accuracy Performance
Each unit is calibrated at the specified frequency with accuracy within 0.1 dB or 1%.
H-Plane Fixed Attenuator Design
Designed for waveguide transmission systems requiring stable attenuation and predictable RF performance.
Calibrated at Specified Frequency
Provides precise attenuation reference tailored to the intended operating frequency.
Stable RF Performance
Maintains consistent attenuation characteristics across the operating band.
Reliable Mechanical Construction
Designed for dependable use in laboratory and instrumentation environments.
Supports Signal Isolation and Level Control
Helps reduce reflections and manage signal levels in RF systems.
Applications
Mi-Wave’s 521 Series Fixed Attenuators are used in microwave and millimeter-wave systems where accurate, fixed attenuation is required.
Generator Isolation
Used to isolate RF signal generators from mismatched load conditions, improving measurement stability and protecting equipment.
Signal Level Reduction
Provides controlled and repeatable attenuation to reduce RF signal levels in waveguide systems.
Power Measurement Range Extension
Enables RF power meters and sensors to operate within safe and accurate measurement ranges by reducing input signal levels.
Waveguide Test Systems
Commonly used in laboratory and instrumentation setups for repeatable RF testing and evaluation.
Calibration and Measurement Setups
Supports systems that require known attenuation values for accurate measurement and reference.
Microwave and Millimeter-Wave Applications
Suitable for use across standard waveguide bands from 8 GHz to 220 GHz.
Frequently Asked Questions (FAQ)
What is the 521 Series Fixed Attenuator?
The 521 Series is a fixed waveguide attenuator that provides a constant, calibrated amount of RF signal reduction.
What attenuation values are available?
The 521 Series is available in standard values from 6 dB to 30 dB.
What frequency range does the 521 Series cover?
These attenuators are available across waveguide bands from approximately 8 GHz to 220 GHz.
How accurate are the 521 Series attenuators?
Each unit is calibrated at the specified frequency and is accurate within 0.1 dB or 1%.
What is an H-plane attenuator?
An H-plane attenuator introduces attenuation within the H-plane of a waveguide, providing stable and predictable RF performance.
What are typical applications for the 521 Series?
They are used for generator isolation, signal level reduction, power measurement extension, and RF test setups.
Are these attenuators suitable for mmWave systems?
Yes. The 521 Series is designed for both microwave and millimeter-wave applications.
RF Attenuator Calculators
These RF attenuator calculators are designed to support microwave and millimeter-wave engineers working with direct reading precision attenuators, waveguide attenuators, and laboratory RF test setups. Use these tools to quickly convert attenuation values, estimate power levels, evaluate cascaded loss, and analyze impedance match performance for systems spanning X-Band through J-Band.
dB to Power Ratio
Convert attenuation or gain in decibels to a linear power ratio.
Power Ratio to dB
Convert a linear power ratio into decibels.
dBm to Watts
Convert RF power in dBm to watts for test and system-level calculations.
Watts to dBm
Convert watts to dBm for RF signal level analysis.
Cascaded Attenuation Calculator
Add multiple attenuator values together to determine total path attenuation.
VSWR to Return Loss
Estimate return loss from a known VSWR value.
Glossary of Fixed Waveguide Attenuator Terms
Attenuator Fundamentals
Fixed Attenuator
An attenuator that provides a constant, predefined amount of signal reduction.
Waveguide Attenuator
An attenuator designed for use in waveguide transmission systems at microwave and millimeter-wave frequencies.
Fixed Waveguide Attenuator
A waveguide component that reduces RF power by a known, non-adjustable amount.
High Power Attenuator
An attenuator designed to handle greater RF input power without damage or degraded performance.
Electrical Performance
Attenuation (dB)
The reduction of RF signal power expressed in decibels.
Fixed Attenuation Value
The specified amount of signal reduction provided by the attenuator, such as 6 dB, 10 dB, 20 dB, or 30 dB.
Accuracy
How closely the actual attenuation matches the specified attenuation value.
Calibration
The process of verifying attenuation performance at a specified frequency.
Insertion Loss
The total signal loss introduced by a component in an RF path, including intended attenuation effects.
Power Handling
The maximum RF power an attenuator can safely dissipate.
RF and Frequency
Radio Frequency (RF)
Electromagnetic signals used in communications, sensing, and measurement systems.
Microwave Frequencies
Frequencies generally ranging from 1 GHz to 30 GHz.
Millimeter-Wave (mmWave)
Frequencies from 30 GHz to 300 GHz used in high-frequency communications, radar, and test systems.
Frequency Range
The span of frequencies over which the attenuator is designed to operate.
Specified Frequency
The exact frequency at which the attenuator is calibrated for its stated attenuation accuracy.
Waveguide and Design Terms
H-Plane Attenuator
A waveguide attenuator designed with attenuation introduced in the H-plane of the waveguide structure.
Waveguide Transmission Line
A metallic structure used to guide microwave and millimeter-wave energy with low loss.
Waveguide Band
A frequency range associated with a specific standard waveguide size.
Stable Attenuation
Consistent attenuation performance under normal operating conditions.
System and Applications
Generator Isolation
Using attenuation to reduce the effects of reflections from mismatched loads on a signal generator.
Mismatched Load Effects
Performance issues caused by reflections when the load impedance does not match the source or transmission line.
Power Measurement Range Extension
Using an attenuator to lower signal levels so they remain within the usable input range of a power meter or sensor.
Signal Source Output Reduction
Reducing the output power of a source by a known amount for testing, calibration, or system integration.
Test and Measurement
The evaluation of RF and microwave components and systems using instrumentation and controlled setups.
Note: Our website contains just a few types of Attenuators we build. Consult with us for your specific needs.
| Model | Band Type | Power Handling | Minimum Frequency (GHz) | Maximum Frequency (GHz) | Attenuation (dB) | Power Handling (CW) | RF Ports | LINK |
|---|---|---|---|---|---|---|---|---|
| 521K-3/595 | K-Band | LOW | 18 | 26.5 | 3 | 10 | WR-42 Waveguide UG-595/U Flange | |
| 521K-6/595 | K-Band | LOW | 18 | 26.5 | 6 | 10 | WR-42 Waveguide UG-595/U Flange | |
| 521K-10/595 | K-Band | LOW | 18 | 26.5 | 10 | 10 | WR-42 Waveguide UG-595/U Flange | |
| 521K-20/595 | K-Band | LOW | 18 | 26.5 | 20 | 10 | WR-42 Waveguide UG-595/U Flange | |
| 521K-30/595 | K-Band | LOW | 18 | 26.5 | 30 | 10 | WR-42 Waveguide UG-595/U Flange | |
| 524K-6/595 | K-Band | HIGH | 18 | 26.5 | 6 | 150 | WR-42 Waveguide UG-595/U Flange | |
| 524K-10/595 | K-Band | HIGH | 18 | 26.5 | 10 | 150 | WR-42 Waveguide UG-595/U Flange | |
| 524K-20/595 | K-Band | HIGH | 18 | 26.5 | 20 | 150 | WR-42 Waveguide UG-595/U Flange | |
| 524K-30/595 | K-Band | HIGH | 18 | 26.5 | 30 | 150 | WR-42 Waveguide UG-595/U Flange | |
| 521A-2/599 | Ka-Band | LOW | 26.5 | 40 | 2 | 10 | WR-42 Waveguide UG-599/U Flange | |
| 521A-3/599 | Ka-Band | LOW | 26.5 | 40 | 3 | 10 | WR-42 Waveguide UG-599/U Flange | |
| 521A-5/599 | Ka-Band | LOW | 26.5 | 40 | 5 | 10 | WR-42 Waveguide UG-599/U Flange | |
| 521A-10/599 | Ka-Band | LOW | 26.5 | 40 | 10 | 10 | WR-42 Waveguide UG-599/U Flange | |
| 521A-20/599 | Ka-Band | LOW | 26.5 | 40 | 20 | 10 | WR-42 Waveguide UG-599/U Flange | |
| 521A-30/599 | Ka-Band | LOW | 26.5 | 40 | 30 | 10 | WR-42 Waveguide UG-599/U Flange | |
| 524A-6/599 | Ka-Band | HIGH | 26.5 | 40 | 6 | 75 | WR-42 Waveguide UG-599/U Flange | |
| 524A-10/599 | Ka-Band | HIGH | 26.5 | 40 | 10 | 75 | WR-42 Waveguide UG-599/U Flange | |
| 524A-20/599 | Ka-Band | HIGH | 26.5 | 40 | 20 | 75 | WR-42 Waveguide UG-599/U Flange | |
| 524A-30/599 | Ka-Band | HIGH | 26.5 | 40 | 30 | 75 | WR-42 Waveguide UG-599/U Flange | |
| 524B-10/383 | Q-Band | HIGH | 33 | 50 | 10 | 20 | WR-22 Waveguide UG-383/U Flange | |
| 524B-20/383 | Q-Band | HIGH | 33 | 50 | 20 | 20 | WR-22 Waveguide UG-383/U Flange | |
| 524B-30/383 | Q-Band | HIGH | 33 | 50 | 30 | 20 | WR-22 Waveguide UG-383/U Flange | |
| 521B-3/383 | Q-Band | LOW | 33 | 50 | 3 | 7 | WR-22 Waveguide UG-383/U Flange | |
| 521B-5/383 | Q-Band | LOW | 33 | 50 | 5 | 7 | WR-22 Waveguide UG-383/U Flange | |
| 521B-10/383 | Q-Band | LOW | 33 | 50 | 10 | 7 | WR-22 Waveguide UG-383/U Flange | |
| 521B-20/383 | Q-Band | LOW | 33 | 50 | 20 | 7 | WR-22 Waveguide UG-383/U Flange | |
| 521B-30/383 | Q-Band | LOW | 33 | 50 | 30 | 7 | WR-22 Waveguide UG-383/U Flange | |
| 521U-3/383 | U-Band | LOW | 40 | 60 | 3 | 5 | WR-19 Waveguide UG-383/U-M Flange | |
| 521U-6/383 | U-Band | LOW | 40 | 60 | 6 | 5 | WR-19 Waveguide UG-383/U-M Flange | |
| 521U-10/383 | U-Band | LOW | 40 | 60 | 10 | 5 | WR-19 Waveguide UG-383/U-M Flange | |
| 521U-20/383 | U-Band | LOW | 40 | 60 | 20 | 5 | WR-19 Waveguide UG-383/U-M Flange | |
| 521U-30/383 | U-Band | LOW | 40 | 60 | 30 | 5 | WR-19 Waveguide UG-383/U-M Flange | |
| 524U-6/383 | U-Band | HIGH | 40 | 60 | 6 | 10 | WR-19 Waveguide UG-383/U-M Flange | |
| 524U-10/383 | U-Band | HIGH | 40 | 60 | 10 | 10 | WR-19 Waveguide UG-383/U-M Flange | |
| 524U-20/383 | U-Band | HIGH | 40 | 60 | 20 | 10 | WR-19 Waveguide UG-383/U-M Flange | |
| 524U-30/383 | U-Band | HIGH | 40 | 60 | 30 | 10 | WR-19 Waveguide UG-383/U-M Flange | |
| 521V-3/385 | V-Band | LOW | 50 | 75 | 3 | 5 | WR-15 Waveguide UG-385/U Flange | |
| 521V-6/385 | V-Band | LOW | 50 | 75 | 6 | 5 | WR-15 Waveguide UG-385/U Flange | |
| 521V-10/385 | V-Band | LOW | 50 | 75 | 10 | 5 | WR-15 Waveguide UG-385/U Flange | |
| 521V-20/385 | V-Band | LOW | 50 | 75 | 20 | 5 | WR-15 Waveguide UG-385/U Flange | |
| 521V-30/385 | V-Band | LOW | 50 | 75 | 30 | 5 | WR-15 Waveguide UG-385/U Flange | |
| 524V-6/385 | V-Band | HIGH | 50 | 75 | 6 | 10 | WR-15 Waveguide UG-385/U Flange | |
| 524V-10/385 | V-Band | HIGH | 50 | 75 | 10 | 10 | WR-15 Waveguide UG-385/U Flange | |
| 524V-20/385 | V-Band | HIGH | 50 | 75 | 20 | 10 | WR-15 Waveguide UG-385/U Flange | |
| 524V-30/385 | V-Band | HIGH | 50 | 75 | 30 | 10 | WR-15 Waveguide UG-385/U Flange | |
| 521E-3/387 | E-Band | LOW | 60 | 90 | 3 | 2 | WR-12 Waveguide UG-387/U Flange | |
| 521E-6/387 | E-Band | LOW | 60 | 90 | 6 | 2 | WR-12 Waveguide UG-387/U Flange | |
| 521E-10/387 | E-Band | LOW | 60 | 90 | 10 | 2 | WR-12 Waveguide UG-387/U Flange | |
| 521E-20/387 | E-Band | LOW | 60 | 90 | 20 | 2 | WR-12 Waveguide UG-387/U Flange | |
| 521E-30/387 | E-Band | LOW | 60 | 90 | 30 | 2 | WR-12 Waveguide UG-387/U Flange | |
| 524E-6/387 | E-Band | HIGH | 60 | 90 | 6 | 10 | WR-12 Waveguide UG-387/U Flange | |
| 524E-10/387 | E-Band | HIGH | 60 | 90 | 10 | 10 | WR-12 Waveguide UG-387/U Flange | |
| 524E-20/387 | E-Band | HIGH | 60 | 90 | 20 | 10 | WR-12 Waveguide UG-387/U Flange | |
| 524E-30/387 | E-Band | HIGH | 60 | 90 | 30 | 10 | WR-12 Waveguide UG-387/U Flange | |
| 521W-3/387 | W-Band | LOW | 75 | 110 | 3 | 2 | WR-10 Waveguide UG-387/U-M Flange | |
| 521W-6/387 | W-Band | LOW | 75 | 110 | 6 | 2 | WR-10 Waveguide UG-387/U-M Flange | |
| 521W-10/387 | W-Band | LOW | 75 | 110 | 10 | 2 | WR-10 Waveguide UG-387/U-M Flange | |
| 521W-20/387 | W-Band | LOW | 75 | 110 | 20 | 2 | WR-10 Waveguide UG-387/U-M Flange | |
| 521W-30/387 | W-Band | LOW | 75 | 110 | 30 | 2 | WR-10 Waveguide UG-387/U-M Flange | |
| 524W-6/387 | W-Band | HIGH | 75 | 110 | 6 | 10 | WR-10 Waveguide UG-387/U-M Flange | |
| 524W-10/387 | W-Band | HIGH | 75 | 110 | 10 | 10 | WR-10 Waveguide UG-387/U-M Flange | |
| 524W-20/387 | W-Band | HIGH | 75 | 110 | 20 | 10 | WR-10 Waveguide UG-387/U-M Flange | |
| 524W-30/387 | W-Band | HIGH | 75 | 110 | 30 | 10 | WR-10 Waveguide UG-387/U-M Flange | |
| 521F-3/387 | F-Band | LOW | 90 | 140 | 3 | 0.1 | WR-8 Waveguide UG-387/U-M Flange | |
| 521F-6/387 | F-Band | LOW | 90 | 140 | 6 | 0.1 | WR-8 Waveguide UG-387/U-M Flange | |
| 521F-10/387 | F-Band | LOW | 90 | 140 | 10 | 0.1 | WR-8 Waveguide UG-387/U-M Flange | |
| 521F-20/387 | F-Band | LOW | 90 | 140 | 20 | 0.1 | WR-8 Waveguide UG-387/U-M Flange | |
| 521F-30/387 | F-Band | LOW | 90 | 140 | 30 | 0.1 | WR-8 Waveguide UG-387/U-M Flange | |
| 524F-6/387 | F-Band | HIGH | 90 | 140 | 6 | 5 | WR-8 Waveguide UG-387/U-M Flange | |
| 524F-10/387 | F-Band | HIGH | 90 | 140 | 10 | 5 | WR-8 Waveguide UG-387/U-M Flange | |
| 524F-20/387 | F-Band | HIGH | 90 | 140 | 20 | 5 | WR-8 Waveguide UG-387/U-M Flange | |
| 524F-30/387 | F-Band | HIGH | 90 | 140 | 30 | 5 | WR-8 Waveguide UG-387/U-M Flange | |
| 521D-3/387 | D-Band | LOW | 110 | 170 | 3 | 0.1 | WR-6 Waveguide UG-387/U-M Flange | |
| 521D-6/387 | D-Band | LOW | 110 | 170 | 6 | 0.1 | WR-6 Waveguide UG-387/U-M Flange | |
| 521D-10/387 | D-Band | LOW | 110 | 170 | 10 | 0.1 | WR-6 Waveguide UG-387/U-M Flange | |
| 521D-20/387 | D-Band | LOW | 110 | 170 | 20 | 0.1 | WR-6 Waveguide UG-387/U-M Flange | |
| 521D-30/387 | D-Band | LOW | 110 | 170 | 30 | 0.1 | WR-6 Waveguide UG-387/U-M Flange | |
| 524D-36/387 | D-Band | HIGH | 110 | 170 | 36 | 2 | WR-6 Waveguide UG-387/U-M Flange | |
| 524D-10/387 | D-Band | HIGH | 110 | 170 | 10 | 2 | WR-6 Waveguide UG-387/U-M Flange | |
| 524D-20/387 | D-Band | HIGH | 110 | 170 | 20 | 2 | WR-6 Waveguide UG-387/U-M Flange | |
| 524D-30/387 | D-Band | HIGH | 110 | 170 | 30 | 2 | WR-6 Waveguide UG-387/U-M Flange | |
| 521G-3/387 | G-Band | LOW | 140 | 220 | 3 | 0.1 | WR-5 WaveguideUG-387/U-M Flange | |
| 521G-6/387 | G-Band | LOW | 140 | 220 | 6 | 0.1 | WR-5 WaveguideUG-387/U-M Flange | |
| 521G-10/387 | G-Band | LOW | 140 | 220 | 10 | 0.1 | WR-5 WaveguideUG-387/U-M Flange | |
| 521G-20/387 | G-Band | LOW | 140 | 220 | 20 | 0.1 | WR-5 WaveguideUG-387/U-M Flange | |
| 521G-30/387 | G-Band | LOW | 140 | 220 | 30 | 0.1 | WR-5 WaveguideUG-387/U-M Flange | |
| 524G-6/387 | G-Band | HIGH | 140 | 220 | 6 | 1 | WR-5 WaveguideUG-387/U-M Flange | |
| 524G-10/387 | G-Band | HIGH | 140 | 220 | 10 | 1 | WR-5 WaveguideUG-387/U-M Flange | |
| 524G-20/387 | G-Band | HIGH | 140 | 220 | 20 | 1 | WR-5 WaveguideUG-387/U-M Flange | |
| 524G-30/387 | G-Band | HIGH | 140 | 220 | 30 | 1 | WR-5 WaveguideUG-387/U-M Flange | |
| 521H-3/387 | H-Band | LOW | 170 | 260 | 3 | 0.1 | WR-4 Waveguide UG-387/U Flange | |
| 521H-5/387 | H-Band | LOW | 170 | 260 | 5 | 0.1 | WR-4 Waveguide UG-387/U Flange | |
| 521H-6/387 | H-Band | LOW | 170 | 260 | 6 | 0.1 | WR-4 Waveguide UG-387/U Flange | |
| 521H-10/387 | H-Band | LOW | 170 | 260 | 10 | 0.1 | WR-4 Waveguide UG-387/U Flange | |
| 521H-20/387 | H-Band | LOW | 170 | 260 | 20 | 0.1 | WR-4 Waveguide UG-387/U Flange | |
| 521H-30/387 | H-Band | LOW | 170 | 260 | 30 | 0.1 | WR-4 Waveguide UG-387/U Flange | |
| 524H-6/387 | H-Band | HIGH | 170 | 260 | 6 | 0.5 | WR-4 Waveguide UG-387/U Flange | |
| 524H-10/387 | H-Band | HIGH | 170 | 260 | 10 | 0.5 | WR-4 Waveguide UG-387/U Flange | |
| 524H-20/387 | H-Band | HIGH | 170 | 260 | 20 | 0.5 | WR-4 Waveguide UG-387/U Flange | |
| 524H-30/387 | H-Band | HIGH | 170 | 260 | 30 | 0.5 | WR-4 Waveguide UG-387/U Flange | |
| 521J-3/387 | J-Band | LOW | 220 | 325 | 3 | 0.05 | WR-3 Waveguide UG-387/U Flange | |
| 521J-5/387 | J-Band | LOW | 220 | 325 | 5 | 0.05 | WR-3 Waveguide UG-387/U Flange | |
| 521J-6/387 | J-Band | LOW | 220 | 325 | 6 | 0.05 | WR-3 Waveguide UG-387/U Flange | |
| 521J-10/387 | J-Band | LOW | 220 | 325 | 10 | 0.05 | WR-3 Waveguide UG-387/U Flange | |
| 521J-20/387 | J-Band | LOW | 220 | 325 | 20 | 0.05 | WR-3 Waveguide UG-387/U Flange | |
| 521J-30/387 | J-Band | LOW | 220 | 325 | 30 | 0.05 | WR-3 Waveguide UG-387/U Flange |



