The document is a resume for Christian Holmstedt summarizing his experience and skills. It outlines his broad experience in radio astronomy systems and receivers, including analog and digital electronics design, electromechanical systems, automation, RF testing, vacuum technology, and clean room work. It also lists his technical skills and work history developing and testing cryogenically cooled low noise receivers for radio telescopes.

1. C H R I S T I A N H O L M S T E D T
holmstedt.christian@gmail.com
(520) 270 6021
http://www.linkedin.com/in/christianholmstedt
S U M M A R Y
Broad experience gained from involvement in several projects related to Radio Astronomy Systems and Receivers at
both component and system level. Especially interested in interdisciplinary design work and problem solving in the
fields of Analog and Digital Electronics, Electromechanical Systems, and Automation.
Comfortable with taking responsibility for a design and taking it from the concept and definitions stage all the way
through design, prototyping, system verification, production, and delivery followed by technical support to the end
user.
Experience with following common engineering design flow processes (design reviews, acceptance testing, acceptance
review, product documentation). Has been involved in both sides of a design review.
• Electronic Design – Mixed signal analog digital design.
• Development of automated test systems – RF test systems, Electromechanical systems, PCB testing.
• Cryogenically cooled low noise receivers – Design, characterization, troubleshooting.
• RF Testing – Scalar & Network Analyzers, Noise measurements, Amplifier testing.
• Vacuum technology – HV & UHV systems (Pumps, Sputters, RIE, Evaporators).
• Clean room work – Micro fabrication (SIS junctions), Photo lithography.
• Programming / Instrument control – LabVIEW, RS-232, CAN, GPIB, TCP-IP, Xilinx CPLD
• Schematic design – OrCAD (Hierarchical design).
• Mechanical drafting – AutoCAD, DesignCAD 3D MAX
• Technical Writing – Test reports, Specifications, Interface Control Documents, Design reports and related
documentation needed for a successful project completion.
S K I L L S
LabVIEW
Data Acquisition
Instrument control
RF / Microwave Engineering
Calibration
System Design
Hardware
Circuit Design
Electrical Engineering
Instrumentation
Network Analyzers
Spectrum Analyzers
Testing
Analog Circuit Design
OrCAD Capture
Automation
System Verification
Technical Writing
Design Reviews
Xilinx CPLD
Test Equipment
Hands-On lab skills
Electromechanical design

2. W O R K E X P E R I E N C E
Adams & Garth Staffing 12 / 2012 - 12 / 2014
Electrical Engineer
Part of the pool of people available on a short to long term basis depending on the clients needs in the field of Electrical
Engineering. Available for both Technician and Engineer level jobs.
New Jersey Institute of Technology 12 / 2013 - 02 / 2014
RF / Electrical Engineer
Responsible for Production and Commissioning of the $1M Analog System for the Expanded Owens Valley Solar Array
(EOVSA) being built at Owens Valley Radio Observatory in California.
Finalized production and tested all assemblies on site at Owens Valley Radio Astronomy (OVRO) in California.
NRAO – National Radio Astronomy Observatory 03 / 2013 - 09 / 2013
Electrical Engineer
Responsible for production, testing, delivery and support of the $1M Analog system (Front End and Back End) for the
Expanded Owens Valley Solar Array (EOVSA) in collaboration with NJIT and OVRO.
Took over responsibility of the analog system after the first prototypes had been designed, tested, delivered, and
reviewed. Implemented needed design changes to improve performance and simplify production. Responsible for
handling procurement of all components, production planning, and (lastly but not least) to build all assemblies.
NRAO (through Adams & Garth Staffing) 12 / 2012 - 03 / 2013
Electronics Technician / Engineer
Joined the Expanded Owens Valley Solar Observatory (EOVSA) project as an Electronics Technician to assemble and
test three prototype Front End and Back End receivers. These were used to gather field data in preparation for the CDR
(Critical Design Review) required to go ahead with production of the systems.
Attended the CDR at the site in Owens Valley and presented the production schedule for these receivers. The work on
this project continued at NRAO where I took over the responsibility for production, testing, and delivery of these
receivers.
NRAO – National Radio Astronomy Observatory 01 / 2002 - 10 / 2012
Electrical Engineer
The Atacama Large Millimeter/sub-millimeter Array (ALMA), an international partnership of Europe, North America and
East Asia in cooperation with the Republic of Chile, is the largest astronomical project in existence. ALMA will be a
single telescope of revolutionary design, composed initially of 66 high precision antennas located on the Chajnantor
plateau, 5000 meters altitude in northern Chile.
The ALMA Front End is a cryogenically cooled low noise receiver that when fully equipped will be a 10 band receiver
working in the frequency range from ~30GHz to ~1THz.
My main responsibilities involve, among many other things, the design, implementation and production of the ALMA

3. Front End DC Power System, the ALMA Front End thermal interlock safety system and to provide technical support for
many other sub assemblies in the receiver system during integration at the ALMA site in Chile. Other main
responsibilities have been the design of the control software for the ALMA Evaluation Receivers used at the ALMA Test
Facility at the VLA in Socorro New Mexico and also the control software for the ALMA Holography Receiver currently in
use at the ALMA site in Chile.
The assignments also include various RF testing and design of automated test systems for performance evaluation of
receiver systems.
GARD – Group for Advanced Receiver Development 06 / 1999 - 01 / 2002
Electrical Engineer
GARD is a group located at Chalmers University of Technology in Gothenburg, Sweden. This group is specializing in
developing technologies, components and systems related to low noise receivers used in the field of Radio Astronomy.
My main responsibility during this time was the design of a unique computer controlled in-vacuum measurement
system for characterization of the beam pattern of the Mixer Sub-Assembly for the HIFI Instrument in the Herschel
Space Telescope (formerly known as the FIRST Project).
The system works at sub-millimeter wave frequencies from 480 - 1250GHz and was designed to characterize the
receiver beams, e.g orientation of the optical axis, size & location of the beam waist in the cryogenically cooled low-
noise SIS receivers used in the HIFI instrument.
The work offered a wide range of challenges and required a broad knowledge and understanding of millimeter-wave
RF components and testing as well as vacuum systems, cryogenic technologies, electromechanical design and material
selection for use with space qualified sub-assemblies and components ranging from component level to system wide
requirements. As well as offering challenges the project was also a great learning experience.
The project was done in collaboration with SRON in the Netherlands and ESA (European Space Agency).
I was also involved in SIS mixer fabrication (clean room work) and characterization, designing a measurement system
for SIS DC characterization at cryogenic temperatures down to 4K.
Ericsson Microwave Systems AB 06 / 1995 - 06 / 1999
Service Engineer / Manager
Manager of Antenna Measuring Range.
Hardware maintenance, component level troubleshooting and repair of Scientific Atlanta Test & Measurement
equipment. Antenna Measurements, Programming (LabVIEW / HP Basic for Windows) Mechanical CAD (AutoSketch,
AutoCAD LT
Chalmers University of Technology 06 / 1989 - 05 / 1995
Research Engineer / Technician
Involved in Research & Development of low noise receivers and devices used in cryogenically cooled receivers
designed for Onsala Space Observatory and SEST (Swedish-ESO Sub-millimeter Telescope) together with guest
scientists from other countries.
A rewarding job involving device level testing as well of manufacturing of superconducting sub-millimeter wave mixer
devices (SIS mixers) and low noise IF amplifier chains. Design and realization of specialized test systems for
characterization of said devices such as liquid He vacuum cryostats, mechanical test fixtures, and computer controlled
measurement systems.
Gained experience in the use of HV / UHV vacuum equipment and leak detection (Sputters, Evaporators, RIE systems)
as well as the use of micro fabrication equipment used for SIS fabrication in clean-room environment (photo

4. lithography, wet and dry etching processes, lift-off, substrate dicing saws).
E D U C A T I O N
Polhems Gymnasiet, Gothenburg Sweden 1985 - 1989
BS degree in Electrical Engineering ; Engineering studies, Electronics.
L A N G U A G E S
English (fluent) Swedish (native) German (limited working proficiency)
P U B L I C A T I O N S
SIS Mixers for Sub-millimeter Wavelengths
Fourth Nordic Symposium on Superconductivity (4th NSSC), 25-28 May, 1994, Varberg, Sweden, Abstracts GIPR-323,
p.132, 1994.
URL : GARD publications (see publication #36)
Authors : Jacobsson S.W., Belitsky V., Holmstedt C., Kollberg E.L.
Fourier Transform Spectrometer Studies (300-1000 GHz) of Nb-based Quasi-Optical SIS Detectors
IEEE Trans. on Appl. Supercond. vol. 5, pp. 3445-3451, Nov. 3, 1995.
URL : IEEE Explore link
Authors : Belitsky V.Yu., Jacobsson S.W., Filippenko L.V, Koshelets, Holmstedt C., Kollberg E.L.
Studies of Josephson Mixing in SIS Junctions
24th European Microwave Conference (Volume 2), 1994
URL : IEEE Explore link
Authors : Koshelets, V., Kovtonyuk, S., Christian Holmstedt, Filippenko, L., Lapitskaya, I., Kollberg, E.L
Receiver triangulation system for Gaussian Beam Measurement Setup
(Acknowledgment of original idea but not listed as an author since I left the group before completion)
System for determining the waist position of a Gaussian Beam at THz frequencies for an In-vacuum Test and
Measurement system. This was a key component used for characterization of the Mixer Sub-Assemblies for the
Herschel Space Telescope.
Proceedings of the Nordic MATLAB Conference, Kopenhagen, Denmark, October 20-21, 2003
URL : GARD publications
Authors : Miroslav Pantaleev, Fredrixon M., Ermisch K., Belitsky V.Yu.

5. Gaussian Beam Measurement Range MATLAB Simulation for ESA FIRST Project
(Acknowledgment of provided work and involvement)
Paper presenting the measurement system designed for the Herschel project (formerly known as FIRST).
Nordisk Matlab Konferens Oktober 17-18, 2001 Oslo, Norge
URL : GARD archive
Authors : Pantaleev M., Belitsky V.Yu.
A D D I T I O N A L I N F O R M A T I O N
Legal Status : US Green Card holder. Can work without restrictions anywhere in the United States.
Nationality : Swedish