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Last Updated on:  Wednesday, June 02, 2021 04:27:30 AM

David Johnson, P.E., received his Professional Engineer Colorado license #17425 in 1980.  He holds eight patents with two more pending.  He brings a comprehensive background in research, product development, applications engineering and project management that can help you prove new product concepts or make cost and performance improvements of existing product. If you would like to discuss ways David Johnson can provide support for your project, please phone or email us.

  • RF
  • Very low power
  • Low level
  • Light to Voltage
  • Current to Volatage
  • Voltage to Current


  • Light
  • Temperature
  • Pressure
  • Humidity
  • Speed
  • Capacitance proximity
  • Mechanical position
  • Human proximity and motion
  • Human finger touch
  • Piezoelectric vibration
  • Ultrasonic
  • Combustible gas
  • Smoke
  • Optical Fiber
  • Gas bubble in blood
  • Electric Field
Power Systems
  • Linear and switch mode power supplies
  • Photovoltaic solar
  • Battery Charger
  • Solid State Relays 
  • Multi-phase alternators

Misc. Systems

  • Security Alarms
  • Wind energy
  • RFID
  • Medical
  • Data acquisition
  • Optical through-the-air Communications
  • Anti-carjacking alarm

Signal Generators

  • RS-170 B&W video
  • Very low power pulse
  • Low power RF
  • Square, triangle and sine wave
  • High Voltage pulse
  • High current pulse
  • Variable pulse width/ height
  • High power audio beepers
  • Modulated light pulse

Control Systems

  • Stepper motors
  • Touch activated switches
  • Jail light and door controls
  • Security access
  • Material handling machines
Faraday Capacitance Proximity Touch Switches Six (6) Models Available           Prices           Place an Order           Project Photos

David A. Johnson, P.E.

Consulting Electronics Engineer

6601 County Road 6410    Lubbock, TX  79416-9717

Phone:  806-778-8407  Central Time Zone

email: dave@discovercircuits.com                    
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Last Updated on: 22 November, 2021 02:42:39 PM

David Johnson & Associates:  Credentials              Design Expertise              Services Offered
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