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First Quarter, 2012                                                                                                                                               Previous Issues     

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

Shooting Range Flasher

Wily received an email message from the owner of a shooting range, not far from his home.  The guy wanted a unique indicating device which would detect when a steel target was hit with a bullet and flash a bright light. 

The guy said that when hit the steel targets he used at his range make a loud “ping” sound.  But, when his shooting range was busy, often a shooter could not always hear the ping sound from his target above the other sounds along the range.  Could Wily come up with something?  Wily was intrigued and scheduled a visit to the guy’s range the next day.....

con't page 7

Wily Widget,
the Lone Inventor
 with Gadget & Gizmo

WHAT THE WORLD NEEDS NOW is an....Old style Wind Mill for Electricity Generation
My new Lubbock Texas home has a lot of wind.  I would love to be able to tap into that renewable energy resource.  However, my neighborhood home owner’s association has covenants which restrict the installation of wind generators on tall towers....
story con't on page 6
Testing LED Light Intensity
By: David Johnson
The human eye is not a good instrument for measuring how bright a light is.  Our eyes tend to be logarithmic.  When making a comparison between two lights, unless one light is considerably brighter than the other, you will not know which is really brighter.  You need a linear device to make such a measurement.

You don’t have to spend a lot of money to make good intensity measurements.  A fairly accurate device is the bare silicon photodiode.  As the cart below illustrates, a silicon photodiode has a broad light response, covering invisible ultraviolet, through the entire visible spectrum, into the invisible near infrared band.  These parts act as small solar cells.  The DC current generated by them is directly proportional to the.....

   story con't on page 4

Power Supply Problems - Excessive +5v Supply Current Drain 

I was troubleshooting a circuit board the other day, which had a +5v power supply problem.  I thought I would walk you through some of my techniques for tracking down power supply problems.  Circuit boards with power supply problems are quite common, mostly due to the number of parts that are touched by a DC supply.  

The board I was fixing was part of a complex video processing circuit I designed some 15 years ago.  One of my old clients had collected about 10 of the old boards and needed them tested and repaired....

 story con't on page 3

Bad Alkaline Battery Charger
A while back I bought a battery charger, which claimed to charge alkaline 1.5v cells.  I seem to use a lot of 1.5v batteries.  I have many flashlights, computer mice and MP3 players which only work with standard 1.5v alkaline cells.  The markings on almost any alkaline battery say that you should not attempt to charge their devices.  They warn that doing so could cause the battery to leak or even explode.  Still, many people claim to have some success in putting some energy back into these otherwise disposable batteries.  The purchased charging device claimed to have the “intelligence” to properly charge batteries.  So, I thought I would test the thing.....

story con't on page 5    

Water Train

Many states in the US are in a brutal drought.  Reservoirs, ponds and lakes, which supply drinking water to many cities, have been drying up.  Even water wells have been forced to go deeper to bring up the valuable water.....

story con't on page 2 

First Quarter,  2012    


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

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