October 29, 2026

Low VSWR or Tight Accuracy at 67 GHz? URF’s 1.85mm Attenuators Deliver Both

Achieving low VSWR and tight attenuation accuracy at the same time across the entire DC to 67 GHz is still one of the harder problems for 1.85mm fixed attenuators on the market today.

URF’s 1.85mm male to female fixed attenuators were built to solve it. The series, 1, 3, 6, 10, and 20 dB, holds a 1.30:1 maximum VSWR and ±0.3 dB typical accuracy throughout the entire band, built for high-frequency network analyzers, signal analyzers, and high-speed digital test setups.

Performance by attenuation value

Attenuation	Part number	VSWR, max	Accuracy, typ	Accuracy, max
1 dB	FA67G-1W01-185MF	1.30:1	±0.3 dB	±0.5 dB
3 dB	FA67G-1W03-185MF	1.30:1	±0.3 dB	±0.5 dB
6 dB	FA67G-1W06-185MF	1.30:1	±0.3 dB	±0.6 dB
10 dB	FA67G-1W10-185MF	1.30:1	±0.3 dB	±0.7 dB
20 dB	FA67G-1W20-185MF	1.30:1	±0.3 dB	−0.8 dB to +1.5 dB

Shared specifications for the series

Parameter	Value
Frequency range	DC to 67 GHz
Impedance	50 Ω
Average power	1 W continuous
Connectors	1.85mm male to 1.85mm female
Outer conductor	Stainless steel, passivated
Center conductor	Beryllium copper, gold plated
Dielectric	PEI
Dimensions	Ø 9 × 22.2 mm
Weight	7 g or less
Mating durability	500 cycles minimum
Operating temperature	−55 °C to +85 °C
Storage temperature	−55 °C to +100 °C
Custom option	VSWR below 1.25:1 for special applications

See the full series in our 67 GHz 1.85mm fixed attenuator collection.

How URF achieved low VSWR and tight accuracy together

URF designed the attenuator chip and the 1.85mm connector as one system, rather than pairing an off-the-shelf chip with a separately sourced connector. The team characterized the connector's own insertion loss and built parameter compensation into the chip for each target attenuation value, so the specified attenuation holds at the connector reference planes instead of drifting by the connector loss. Input and output matching were optimized together across the full band to hold VSWR at or below 1.3:1.

Working within our production process, the design went through multiple rounds of prototyping, testing, and iteration before release. The result is a series that holds both specs at the same time from DC to 67 GHz, instead of trading one for the other.

Measured performance in action

VSWR and attenuation vs. frequency, DC to 67 GHz, URF 10 dB 1.85mm fixed attenuator DC to 67 GHz, 1.85mm, 10 dB Fixed Attenuator data shown above.

Applications for a 67 GHz fixed attenuator

67 GHz VNA measurements. Padding test ports to improve effective source and load match and reduce mismatch uncertainty in S-parameter measurements.
Analyzer, scope, and BERT input protection. Keeping instrument inputs within their linear range when testing high-power or high-gain DUTs.
112G/224G PAM4 SerDes and interconnect test. Setting signal levels in 67 GHz bandwidth channels without degrading return loss.
5G FR2-2 and 6G V-band research. Precise level control for receiver sensitivity, linearity, and link budget testing up to 67 GHz.
60 GHz radio and sensing. Repeatable path loss for 802.11ad/ay link and short-range radar development.
Amplifier and mixer characterization. Isolating stages and suppressing standing waves when measuring gain, compression, and conversion loss.
Satellite and aerospace mmWave subsystems. Inter-satellite link and payload testing, with a −55 °C to +85 °C operating range.

Get the right attenuator for your 67 GHz setup

Every value in the series holds 1.30:1 max VSWR and ±0.3 dB typical accuracy from DC to 67 GHz. Browse the 67 GHz 1.85mm fixed attenuator collection, or contact our team for volume pricing and custom low-VSWR options.