About Frequency Electronics, Inc.

Over 60 years of precision timing innovation. From atomic clocks for GPS III to defense-critical synchronization systems.

Our History

Founded in 1961 and headquartered on Long Island, New York, FEI has spent more than six decades advancing the science and engineering of precision timing and frequency control.

From its earliest days, the company established itself as a trusted provider of highly specialized timing, synchronization, and frequency generation technologies for some of the world's most demanding applications. As communications, navigation, defense, and space systems became increasingly dependent on precise timing, FEI developed the expertise and products required to meet stringent performance, reliability, and environmental requirements.

Over the years, the company evolved from a defense-focused contractor into a leading developer of advanced timing and frequency solutions supporting commercial, government, aerospace, and military customers worldwide. Its technologies have been deployed across terrestrial, airborne, maritime, and space-based platforms where accuracy, stability, and resilience are mission-critical.

Today, FEI designs and manufactures atomic clocks, precision frequency references, synchronization systems, microwave subsystems, and advanced positioning, navigation, and timing solutions. Through its family of specialized operating companies, the organization serves a broad range of applications including satellite communications, military communications, radar systems, electronic warfare, aerospace platforms, secure government networks, and critical infrastructure.

The company's longstanding reputation is built on deep engineering expertise, a commitment to technical excellence, and a proven ability to solve complex timing and synchronization challenges in environments where failure is not an option.

As new technologies emerge—including resilient positioning, navigation and timing systems, advanced space architectures, electronic warfare platforms, and next-generation sensing applications—FEI continues to innovate, applying decades of precision timing expertise to the challenges of the future.

Executive Leadership

Thomas A. McClelland, Ph.D.

Thomas A. McClelland, Ph.D.

President & CEO

Dr. McClelland brings 30+ years of aerospace and defense engineering leadership. Doctorate in Physics from Columbia University, pioneer in quantum sensing and precision timing systems.

Steven L. Bernstein

Steven L. Bernstein

Chief Financial Officer

CFO since 2016, joined as Controller in 2010. CPA with 15+ years in financial reporting, budgeting, and auditing. Honors graduate, Queens College CUNY.

Oleandro Mancini

Oleandro Mancini

Senior Vice President, Business Development

Sr. Vice President of Business Development since 2000, with prior VP roles at Satellite Transmission Systems, Cardion Inc. (Siemens), and VP Engineering at Cardion.

Certifications & Standards

FEI maintains rigorous quality, compliance, and security standards across all operations. Our certifications reflect decades of commitment to manufacturing excellence, defense-grade security, and environmental responsibility.

  • ISO 9001:2015ISO
  • AS9100DSAE International
  • ITAR RegisteredU.S. State Dept.
  • RoHS CompliantEU Directive
RF engineers characterising phase noise performance on FEI oscillator hardware
FEI-NY atomic clock module assembly

Facilities & Offices

Corporate Headquarters

Uniondale, NY

Main manufacturing and R&D facility. Home to atomic clock production, frequency standard qualification labs, and advanced research teams.

55 Charles Lindbergh Boulevard, Uniondale, New York 11553

+1 (516) 794-4500

FEI-Zyfer, Inc.

Garden Grove, CA

GPS-based timing and network synchronization. Specializing in assured PNT solutions and telecom timing applications.

7321 Lincoln Way, Garden Grove, CA 92841-1428

+1 (714) 933-4000

FEI - Colorado

Boulder, CO

Focuses on quantum solutions and time and frequency engineering — advancing next-generation capabilities for precision timing and navigation.

2830 Wilderness Place, Boulder, CO 80301

+1 (516) 794-4500

FEI-NJ

Northvale, NJ

Advanced RF, microwave, and electronic-warfare technologies for mission-critical applications.

260 Union Street, Northvale, NJ 07647

+1 (201) 767-8030

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Ready to work with FEI?

Explore our solutions, view products, or contact our team to discuss your mission-critical timing requirements.