Pendulum Electromagnetics, Inc. (PendEl)

Vacuum Electron Device Engineering, Fabrication, and Related Processes

PendEl designs and manufactures unique, high-power continuous wave (CW) and pulse traveling-wave tubes (TWT) and related vacuum electron device assemblies. Located in Raleigh, North Carolina, near the renowned Research Triangle Park, we provide production and custom broadband microwave vacuum electron devices, electron guns, and other vacuum assemblies for a variety of commercial and military applications worldwide.

Pendulum Logo

Design

Manufacturing

Testing

Refurbishment

Engineering Guided by Experience

PendEl’s core competitive TWT technology rests on the use of brazed beryllia blocks to support the helix circuit (slow-wave structure) in the tube body rather than the traditional compression-fit dielectric rod topology employed by others. The resultant block-supported structure exhibits much greater tolerance to both heat and reflected power.

Electron Gun Fabrication

PendEl eguns are modeled using modern particle trajectory codes and fabricated in our well-equipped VED facility.

Klystron Repair

PendEl has been successful refurbishing production quantities of high-powered CW klystrons.

Helix Comparison

Compare PendEl’s brazed block technology to conventional rod-supported technology in this side-by-side view.

PendEl Brazed Block Circuits

See the PendEl difference in this close-up detail of the superior PendEl brazed block technology for helix circuit support.

TWT Fabrication

Explore the components, processes, and systems comprising PendEl’s meticulous and precise VED fabrication activity.

Operating Principle

Check out this live visual representation of velocity modulation of the electron beam in a coupled-cavity TWT.

About PendEl

PendEl was founded in 1994 for the purpose of repairing klystrons and traveling-wave tubes (TWTs). Our highly experienced staff built on that foundation to expand activities, broaden the customer base, and grow the product line. Today, we are focused on growing the TWT catalog beyond the present suite of high-power L-Band devices, marketing a variety of electron gun designs, and supplying general vacuum electron device process services.

PendEl possesses all the infrastructure and equipment necessary to fabricate and process vacuum electron devices, including braze furnaces, RF induction brazing system, helium leak detector, laser welder, exhaust stations, chem lab, mechanical measuring instruments, magnet charger, network analyzers, and high-voltage test stands. And most important, PendEl possesses a talented and adroit technical staff capable of fully exploiting these resources in dedicated service to our customers.

Services

Design

Our expert team combines experience with sophisticated computer modeling to design state-of-the-art TWTs, electron guns, and related subassemblies.

Manufacturing

Our modern Raleigh, NC facility possesses the latest (and earliest) fabrication technology, including vacuum and atmosphere batch brazing furnaces, a push-through atmosphere furnace, RF induction brazing system, 6000W-peak laser welder, double-vacuum exhaust stations, and a small but well-equipped machine shop.

Testing

Our test and processing infrastructure comprises several CW and pulse high voltage/power test stands, Agilent scalar and vector network analyzers, RF sweep generators, time domain relectometer, RF power meters, and an extensive variety of high-power couplers and loads.

Repair

The reliable refurbishment of klystrons and traveling-wave tubes (TWTs) has been a core activity since 1994. Thorough mechanical analysis, attention to detail, and rigorous electrical testing and processing enhance the life and performance of any device we repair or rebuild.

Optimizing Technology for Today’s VED Requirements

With a firm foundation as a reliable repair facility for klystrons, traveling-wave tubes (TWTs), and other vacuum electron devices since 1994, we have leveraged our knowledge, experience, and technology to grow our product line and broaden our customer base. Today, PendEl is a trusted supplier in the design, manufacture, and testing of niche TWTs, electron guns, and related vacuum device services.

Case Study

Jefferson Lab

When The Thomas Jefferson National Accelerator Facility (TJNAF) in Newport News, VA, a high-level physics laboratory investigating quarks and gluons, the fundamental particles comprising all matter, needed a repair facility in 1995 to rebuild and refurbish a population of 150 high-power CW klytrons, they selected PendEl. In what was to become a recurring theme, the assessment by Jefferson Lab personnel was that PendEl performance far exceeded expectations. We continue to work with JLAB as a klystron repair facility.

Case Study

US Army

One aspect of the mostly classified mission of the Army’s Albuquerque, NM, Big Crow Program Office was electromagnetic vulnerability assessment and radar threat simulation. In the immediate aftermath of 9/11 in 2001, PendEl was tasked with providing, on short notice, a suite of two L-Band traveling wave tube amplifiers for use (we later learned) in an upcoming black operation in Afghanistan. A TWTA is a TWT combined with the power supply and peripheral electronics all in one chassis — a transmitter, essentially. Without any formal design on paper, the PendEl team proceeded to fabricate two 1kW CW L-Band TWTA units. The first unit was built from scratch over a period of three days, with key members of the team literally working for 48 hours straight, without any sleep. We did not have time to burn in these units or perform any rigorous testing, so our usual confidence was tempered somewhat upon delivering the transmitters. Nevertheless, we later learned both units had been deployed in land vehicles and aircraft and had performed flawlessly and without incident. So impressed was Big Crow, they visited our facility to present a small award and express their appreciation.

Case Study

US Navy

To this day, PendEl punches well above its weight. When the US Navy expressed a requirement in 2019 to supplement their inventory of a specific solenoid-focused, hollow beam, high-power CW TWT for use aboard its EA-18G Standoff Jammer platform, the AN/ALQ-99, PendEl not only demonstrated the ability to repair existing devices to full specification, but also to fabricate from scratch brand-new devices using existing 1980s documentation (blueprints). PendEl’s performance exceeded expectations at every level of Navy AN/ALQ-99 program management.*

 
*Approved for public release: distribution is unlimited.

“While our services and product line have changed since 1994, our assiduous attention to detail, engineering innovation, and especially, customer service have not”

Facility

PendEl is based in Raleigh, North Carolina, in the renowned Research Triangle area, minutes from RDU international airport.

Location

6304-D Westgate Road, Raleigh, NC 27617

Phone

919-571-9970