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Resume of  David A. Johnson, P.E.
David A. Johnson, PE   -   DiscoverCircuits.com
6601 County Road 6410    Lubbock, TX  79416-9717

Phone:  806-778-8407  (Central Time)                    Dave@discovercircuits.com

30+ years of project management experience, leading by example. 
  • Managing mechanical, electrical and software engineers. 
  • Supervising technicians, CAD operators, assembly workers and subcontractors.
  • Interfacing with customers while supporting marketing and sales departments.   
  • Generating product definitions and specifications.  
  • Researching new technologies and conducting proof of concept experiments.  
  • Describing microprocessor operations, interface and controls.   
  • Defining project goals and objectives.    
  • Estimating project cost and managing project budget.   
  • Planning manpower needs, interviewing and hiring necessary personnel.   
  • Prioritizing, delegating and scheduling project tasks.  
  • Assisting engineers with design problems, prototype construction and testing.  
  • Overseeing U.L, CSA and FCC acceptance testing.  
  • Writing progress reports and conducting product demonstrations.   
  • Generating patent applications. 
  • Skilled at taking a product from concept to mass production.  
20+ years of electronic circuit design and new product development.
  • Areas of expertise include analog circuit design, electro optics, optical communications, optical sensors, switch mode and linear power supplies, amplifiers, instrumentation sensors, signal generators, signal processors and control systems.
  • Also defining microcomputer interface, operations and controls.
  • Expert with the use of most electronics laboratory equipment.
  • Skilled at circuit component selection (based on cost, performance and availability), schematic generation using Orcad and Accel EDA CAD programs, breadboard construction, testing and troubleshooting.
  • In addition, very familiar with printed circuit board design procedures and PCB fabrication requirements.
  • Expert at modifying existing products for special needs and completing applications engineering tasks.
  • Have personally designed, built and tested thousands of circuits.
  • University of Idaho, Bachelor of Science Degree, EE
  • Colorado Registered Professional Engineer
  • Holds eight patents with two more patents pending.
    • Chief designer of a new RFID card reader that cost about one half the reader it replaced.  Developed a very low power radio frequency identification (RFID) card reading system.  The system was used as a replacement to hotel room door lock keys.  Received US patent #6,476,708.

    • Helped develop a wireless method to monitor the air pressure and temperature inside an automobile tire.  The system used a custom radio frequency identification (RFID) circuit.  A special antenna allowed an external magnetic excitation field to power the RFID circuit and retrieve the tire data.    Received US patent #7,019,711 (Coupled transponder and antenna system and method) and one Brazilian patent.

    • Helped develop a complete video interactive archery/firearm shooting range system.  System projected moving targets onto a fabric screen using a computer, laser disk player and video projector. Reflector tipped arrows and an infrared CCD camera determined where the arrows hit the target. Also developed a similar shooting range system that used infrared laser equipped pistols, rifles and shotguns. Systems launched laser light pulses at screen targets instead of arrows.500+ installations now installed and operating. Wrote detailed descriptions for a patent application on the techniques used. (Method and apparatus enabling archery practice)  Received US patent #5,566,951.

    • Conducted research and designed to detect, count and size air bubbles in blood using ultrasound techniques. Bubbles with volumes less than 1 nanoliter were detectable. Circuit used in a kidney dialysis machine. Designed and built a portable battery powered bubble monitor used by the company's sales force to show potential buyers the bubble-free nature of the disposable dialysis machine tubing sets. Wrote circuit descriptions for a patent application on the bubble detector system.  Received US patent #5,394,732, (Method and apparatus for ultrasonic detection of air bubbles)  Japan patent #2823513 and European patent

    • Developed a product that monitored the resistance of a domestic earth ground connection.  The circuit also measured the earth ground current and the voltage with respect to the power line neutral wire.  System was used in conjunction with a transient voltage suppression system.   Received US Patent 7,023,680 (Transient voltage protection and ground status monitoring apparatus and method)

    • Developed a system to monitor the concentration of a soap/water mixture used in carwash soap dispensing systems.  The method used an optical technique to maintain the desired soap concentration.  Wrote a description of the electronic circuit used in the monitor.  Over 3,000 systems were installed.  One patent pending.

    • Chief designer of a new RFID card reader that cost about one half the reader it replaced.  Developed a very low power radio frequency identification (RFID) card reading system.  The system was used as a replacement to hotel room door lock keys.  Received US patent # 6,476,708.  (Detection of an RFID device by an RF reader unit operating in a reduced power state)

    • Designed a system to flash large banks of conventional 40 watt fluorescent lamps synchronized to a CCD camera system.  UV light produced by the lamps allowed “glow-in-the-dark” makeup to be placed on the face and arms of actors. Movement of actors could then be recorded using the CCD cameras.   Systems are currently being used to produce animated movies.   Received US Patent #7,567,293

    •  Developed a system to monitor the concentration of a soap/water mixture used in carwash soap dispensing systems.  The method used an optical technique to maintain the desired soap concentration.  Wrote a description of the electronic circuit used in the monitor.  Over 3,000 systems were installed.   Received US Patent #7,300,197


  • Published many articles and circuits in EDN, Electronic Design, Popular Electronics and Midnight Engineering magazines. Produced an extensive 10MB Internet web site that promotes consulting engineering services. The site also has a 250+ page e-zine of useful information on general science, technology, creativity, science experiments, inventing and electro optics.
  • Developed several families of touch activated AC and DC electronic switches. Switches were mostly used to control lights, doors and intercoms in jail cells. Switches had to survive severe abuse without requiring replacement. Designed and developed a complete jail door control and monitoring system for Colorado Arapahoe County jail as well as several other jails in Texas, Florida, New York and California. Sent the line of products through CSA, CKC and UL safety testing programs. Developed another line of very low power DC capacitance proximity switches. One switch operates up to 5 years on a single 1.5v button battery.
  • Designed, built and successfully demonstrated an optical through the air communications link with a range of 6 miles. Also demonstrated the feasibility of using clouds as large light pulse reflectors. In addition, conducted tests on atmospheric attenuation of light pulses under various weather conditions. Proposed methods for a 40 mile telemetry link using a xenon flash light source. Proposed uses for nitrogen spark light sources. Uses included optical radar and long range distance measurements. Proposed a wide area optical information broadcasting system that would cover an entire metropolitan area with high speed data services.
  • Designed and developed several new consumer products, including cordless telephones, combustible gas detectors, smoke detectors, backup alarms, anti-carjacking alarms, coin operated panorama telescopes and motion intrusion alarms. The motion alarm worked on the basis of monitoring the disturbance of the earth's natural electric field. Wrote patent papers on the intrusion alarm system.
  • Solved a large number of engineering, industrial and medical instrumentation problems for a variety of companies. Designed and built many custom test stations and fixtures.   Advised many companies on ways to reduce manufacturing cost and improve quality.   Led brainstorm sessions to produce new product ideas and new applications for existing products.
  • Constructed many special test stations and special instruments for explosive devices, including initiator testers for Ford and GM airbags. Designed and constructed explosive flash detector/timer monitors. Monitors measured and tested the delay between primer impact and actual explosion. Designed and constructed a laser welder process controller. Controller used an optical fiber probe to monitor and count laser light flashes during welding. Designed a computer controlled test station to test components used on the Trident missile.
  • Evaluated a special color NTSC video enhancement circuit for use in consumer TVs for a large cable company. Designed and built a prototype circuit to test picture improvements. Wrote detailed report of findings. Also designed and built several custom video signal test generators that were used in medial camera applications.
June, 1982Present  (* denotes full-time employment during this time period)
DAVID JOHNSON, Consulting Engineer
Led numerous client/consultant meetings to discuss specific client needs. Generated detailed project descriptions, proposals and engineering cost estimates. Evaluated client company circuit designs, conducted feasibility studies and built prototype systems. Conducted research on new products. Designed and constructed special test instruments. Designed printed circuit boards, generated complete product documentation packages and analyzed product field failures. Hired and managed numerous engineers, programmers, PCB designers and technicians as both employees and subcontractors. Wrote detailed descriptions for several patent applications. Completed over 600 projects for more than 100 different companies.

* September, 2000 to February, 2001
Conducted sustaining engineering for a 100 watt uninterruptible computer power supply (UPS).   Designed several product test fixtures and compoenet testers.   Designed a battery tester that discharged a battery with either a constant current or a constant power load.  Designed a 100 watt DC to AC inverter for supplying continuous AC power to a computer system.   Designed a percision AC wattmeter.    Laid off when Boulder office closed.

*  November, 1999 to August, 2000    CROSSLINK INC, Senior Engineering Project Manager
Managed several radio frequency identification (RFID) projects. RFID tags and tag readers operated at 2.45GHz and 915MHz. Battery powered tags operated for up to 5 years with read ranges in excess or 500 feet.2.45GHz system operated using low a power long-range "backscatter" technique. Also designed 915MHz RF linked sensors.
*  December 1996September 1998 HID CORP, Senior Project Engineer
Conducted research on new passive radio frequency identification devices (RFID) operating at 125KHz and 13.56MHz. Also experimented with battery powered RFID tags operating at 315MHz. One prototype system was designed to provide continuous operation for 5 years. Chief designer of a new RFID card reader that cost about one half the reader it replaced. Developed a method to detect nearby RFID cards using super low power techniques for a battery powered RFID card reader used in security door locks (2 patents pending). Supervised several engineers, technicians and programmers.
October 1980June 1982 MARTIN MARIETTA AEROSPACE, Senior Staff Engineer
Designed power generation and distribution systems using large concentrator type suntracking photovoltaic arrays. Proposed ways to increase efficiency and reduce cost of the systems. Conducted research on very high speed local area networks using optical fibers. Wrote a detailed report that advised military and aerospace centers the use of optical fiber networks. Devised a new fiber optic network coupler with 64 nodes running at 220Mb/sec.
November 1979October 1980 CUSTOM ENGINEERING, Electronics Engineer
Designed special electronic instruments, designed and developed new products. Duties included outlining work scope, estimating manufacturing costs, budgeting, scheduling and supervising product assembly. Coordinated the design and construction of prototypes, wrote detailed assembly procedures and generated necessary support documents. Supervised one engineer, three technicians, several assembly workers and one draftsman.

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