H. P. Friedrichs (AC7ZL) Homepage












My Resume

I am always interested in new technical challenges and opportunities. If you represent or know of an organization in the Tucson, AZ metropolitan area that offers such opportunity and could benefit from my experience and skill set, I would like very much to hear from you. Simply click on the "Contact Me" link for emailing instructions.

Below is an extract from my resume. HTML is really horrible for this type of document, but I do have a more formal version prepared in Microsoft Word, should one wish to see it.

As you can see, my background is varied and multidisciplinary. This means that I can manage and drive projects from start to finish, from concept to physical implementation, and from the system to component and bit level. I am effective at managing teams of technical people, and I take pleasure in helping to mentor or otherwise develop them.


Extracted from the Resume of

H. P. Friedrichs

Skill Summary

Thirty years experience in a variety of engineering functions including technical project/personnel management, hardware/software systems integration, design, implementation and repair of electronic hardware and software, and technical documentation. Fields of activity include computer, instrumentation, automotive, audio, aerospace, radio, medical, and test equipment.

Programming languages: Assembler (Z80/64180, Microchip PIC, 8051), C/C++, FORTRAN, Pascal, Python, HTML, Clipper (dBase), SQL, Powerbuilder, DICOM

Operating systems: Linux/Unix, Windows, OS2, DOS, and embedded realtime kernels (RTOS)

Hardware: Discrete, chip, and board-level analog, digital, and mixed-signal circuitry. PCB design. Factory automation, data collection equipment (transponders and bar code readers). Medical equipment and recording studio audio. Communications gear including RS-232, 422, broadband and TCP/IP. 3 phase power and cryogenic controls. Avionics test sets and other precision pneumatics. Lasers, motion control electronics.


Work History

Principal Engineer/Team Lead:  Honeywell Engines, Systems, and Accessories, Tucson, Arizona  (1995 to present)

Production support and creation of proprietary computerized test instrumentation for military and aerospace components. Highlights include:

Managed capital projects.

Managed test equipment group consisting of four engineers, four technicians, and five contractors -- reduced influx of equipment complaints 30% in first two years

Established and stocked laboratory/workshop for repair and R&D

Developed department P&P's, work instructions and standards for supplementary workforce

Responsible for design and construction of proprietary computer controlled precision pneumatic test set. Efforts resulted in U.S. patent 6,955,184.

Responsible for design and construction of proprietary pressure transfer standard. Efforts resulted in U.S. patent 7,275,445.

Responsible for design and construction of self-cleaning smoke densitometry instrument. Efforts resulted in U.S. Patent 7319524

Circuit board design and layout for test equipment

Software creation and maintenance


Electrical Engineer: Chrysler Corporation, Arizona Proving Grounds, Wittman, Arizona. (1994 to 1995)

Support of test instrumentation and creation of software. Highlights include:

Designed and constructed proprietary vehicle tracking telemetry system. Efforts resulted in two U.S. patents 5,900,828 and 6,005,517

Developed "ACT" (Access Control and Trip management) System using Powerbuilder and SQL.

Designed and installed 96 node 10BaseT network for facility

Repair and maintenance of weather station, dynamometers, power inverters, and comm gear.


Electrical Engineer/Team Lead: Ford Motor Company, Wixom Assembly Plant, Wixom, Michigan (1990 to 1994)

Designed, coded, and installed various pieces of factory automation and data collection equipment. Highlights include:

Responsible for design and implementation of plant-wide VIN/build-code broadcast system, including wiring database

Responsible for installation/programming of unit controllers, barcode readers, and microwave transponders. Coded data collection and parsing software

Responsible for coding and deployment of vehicle sequencing early warning system

Coded databases for VIN number archive system, recall tracking system, critical fastener SPC (statistical process control) system, and telephone/autopager system


Earlier assignments/projects available on request.


External/Extracurricular Projects

PX Body Monitor -- Designed, coded, and fabricated prototype instrument for collecting data on the spatial positioning of non-ambulatory medical patients for the purpose of preventing decubitus ulcers

"Dreamcatcher" -- Designed, coded, and fabricated prototype instrument for the collection of data when patients enter REM sleep. Apparatus was intended for psychiatric studies into improved treatment of persons who have suffered severe emotional trauma

IRYS -- Designed and coded DICOM compliant post-processing software to execute the automatic cancellation of bone tissue from CT angiogram images. The software was intended to improve image quality and eliminate the need for manual editing of images




Bachelor of Science in Electrical Engineering, (November 1988) Lawrence Technological University, Southfield, Michigan

Registered Professional Engineering Exam: Part I


Additional Training/Classes

IBM Programming OS/2 PM Manager I and II, National Instruments CVI, NI Teststand

ESD Procedures

TQ (Total Quality), Root Cause Analysis, Six Sigma Greenbelt

Accounting, The 7 Habits of Highly Effective People, Behavioral Interviewing



Licensed Radio Amateur, Extra Class, (AC7ZL)

Licensed Commercial Radio Operator with Radar Endorsement, (PG00046814)

GMDSS Operator/Maintainer with Radar Endorsement,  (DB00001029)



US 5,900,828  Modemless transmitter for test vehicle tracking system   

US 6,005,517  Test vehicle tracking system

US 6,955,184  Pneumatic generator system for simulating operating conditions of an aircraft

US 7,275,445  Modular pressure sensor drive connectable to a computer

US 7,319,524  Air Purged Optical Densitometer



Authored Book: The Voice of the Crystal: (How to build working radio receiver components entirely from scratch), 185 pages, ISBN: 0967190509  

Authored Book: Instruments of Amplification: (Fun With Homemade Tubes, Transistors, and More), 302 pages, ISBN: 0967190517

Misc Articles for QST

Misc Articles for Eham.com

Misc Articles for the Xtal Set Society

Presentation/Lecture: "Post-Apocalypic Engineering? Experiments in the Construction of Functional Radio Equipment from Virtually Nothing" Presented to the Society of Amateur Science in Las Vegas, NV, 2004

Presentation/Lecture: "Digging Dirt on Inductors: Experiments with Custom Magnetics Made from "Black Sand." Presented to QSO Today's Ham Radio Expo 2020



Society for Amateur Science (SAS), Xtal Set Society (XSS), American Radio Relay League (ARRL), International Morse Preservation Society (FISTS), Narrow Bandwidth Television Association (NBTVA)


 (revised 09/06/2020)