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Second Quarter, 2012                                                                                                                                          Previous Issues     
  

Let's drop in on Wily and look over his shoulder at his latest project....

Illuminated Banister

Wily was reading a magazine when his phone rang.  The call was coming from a large building contractor in a major city. They were going to build some new homes for a subdivision.  The architect specified a touch activated illuminated banister, which was to illuminate the stairs leading to a large basement. At each end of the railing was a metal button.  When the button was touched with a finger, the light would turn on.  When touched again, the light would turn off.  The LED light strip inside the translucent plastic railing was to be powered by 12vac and would draw about 25 watts. ....
con't page 7

Wily Widget,
the Lone Inventor
 with Gadget & Gizmo

WHAT THE WORLD NEEDS NOW is a....Big Dial Wind Speed Indicator
My new home in Lubbock Texas is blessed, or cursed, with lots of wind.  At times the gusts can reach 60MPH.  When the wind is about 40MPH, we have found it impossible to do any work in the back yard.  What I would like to see is a wind speed indicator with an easy to read big dial, similar to many outside temperature dials.  Perhaps the dial would be about 12 inches in diameter with a clear plastic cover.  With such a device can look outside and determine if it is too windy.....
story con't on page 6
AC Current Test Source
By: David Johnson
                                                                                                            
With that resistor I can easily get up to 20 Amps of current.  So far, that has been high enough for me.  The shunt resistor allows me to use my multimeter to accurately measure the AC voltage across the resistor, which is then proportional to the AC current.  In most of my tests, the AC current is a loop.....

   story con't on page 4

 15 Minute Timer Does Not Time Out    

I received a call from an old client.  They said that some infrared LEDs in a circuit I had designed many years ago were fading. The light they emitted was no longer was enough to do the job. I asked them to send me a working unit and all the documentation.  The system was designed to produce an intense flash of 880nm infrared light using an array of 27 LEDs.  The LEDs were driven hard but for only 100ms at a time.  I had my doubts that even after 1000s of flashes the LEDs would not be producing the same amount of light. After I had received the documentation package, I discovered that extensive changes had been made by someone else long after I was no longer involved with the project.  To my shock, I saw a 555 timer circuit being used as a 15 minute timer.....

 story con't on page 3

Bad Chinese Lag Screws
I’ve been building some 4ft by 8ft cedar raised bed boxes for my wife’s garden in Lubbock Texas.  She wants a total of 20 boxes built. The design is pretty simple.  As shown below, each box is made of 6 cedar 2 x 8 boards screwed into 4 x 4 cedar corner posts.  The design called for two 5 inch long 5/16” galvanized lag screws to secure each board to the 4 x 4 post.  There are a total of 32 screws per box.....


story con't on page 5    


Second Quarter,  2012    

 


Imagineering Ezine    Discover Solar Energy Dave Johnson & Associates Faraday Touch Switches



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