Circuits designed by David Johnson, P.E.
Last Updated on: Friday, December 29, 2017 02:53 AM

List of Dave's Circuit Designs

Text & Graphics Copyright © David A. Johnson, PE  --  ALL Rights Reserved.
LINKING to Dave's circuits is permitted but DO NOT COPY CONTENT to your WEB SITE server!

Closet Light with Automatic 3-Minute Timeout

Darkroom Camera Shutter Timer

Divide By 1.5 Counter

Garage Door Closer

Laser Used as Vehicular Traffic Counter

Line Powered 60hz Clock Generator

Long Period Computer Watch Dog Timer

Low Power Oscillators

On/Off Flip/Flop Circuit with Automatic Timeout

On/Off Latch Circuit with 2 Second Delay

On/off Pushbutton Switch with 30 Minute Timeout

Pushbutton Activates Service Request Beeper

Three-Minute Closet Light

Time Garage Door to Close

Two Transistor Oscillators

15 Minute Timer Does Not Time Out

2 Transistor Oscillators

36-Hour Watchdog Timer

3-Minute Closet Light

3-Minute Closet Light #2

555 Timer Forms Simple PWM Motor Controller

Accurate One Shot Pulse Generator

Chicken Coop Door Opener with Timer

Circuit Forms Divide By 1.5 Counter