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Issue 15,  March 2011- Page 1                                                                                                      Previous Issues     

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

Battery Charging Generator Starter

Wily was clearing his driveway of snow when he got a call.  It came from a company who makes custom propane fueled electrical generators.  Their devices were modified RV generators specifically designed for backup power for homes off the utility grid.  Instead of producing AC power, as most emergency power generators, the companyís generator was designed to charge up a large lead-acid battery bank.  When the battery voltage reached a critical point, the generator automatically kicked into operation and ran until the battery was fully charged. 

The company said that for the most part their machines worked fine but they were having problems with their engine starting mechanism.  This engine was started with a conventional starter motor, which was engaged to a gear on the engine shaft using a solenoid.  The solenoid and motor were powered by a small 12 volt battery.  The caller said that the engine often didnít start properly. They wondered if Wily had any suggestions.
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Wily Widget,
the Lone Inventor
 with Gadget & Gizmo

WHAT THE WORLD NEEDS NOW is a....Emergency Electrical Power System
In times of a local or perhaps even a national disaster, utility power may be lost for a prolonged period of time.  How could a family cope without electricity?  What I would like to see is a portable emergency electrical power system, which could support a family for an extended time.  The available power would be minimal but it could be a real life saver.....
story con't on page 6
Improved Solar Powered Path Light
By: David Johnson
Over the last decade or so solar powered garden and path lights have become quite popular.  However, over the last few years I have seen a gradual decline in their use.  I think one of the reasons for this is a huge drop in quality for these devices.  Chinese manufactures have whittled down their designs until they just barely work....

   story con't on page 4

Schottky Diode Leakage Current       

I got a call from a company who was scratching their head about the short battery life of their 3v lithium battery powered product.  Their engineers said that the battery would last for years but testing had shown that the battery only lasted a few months.  They needed my help to figure out where the excess current was going.....

 story con't on page 3

Bad LED Path Light II
My wife knows I love LED products.  A while back she spotted a solar powered LED path light at the dollar store.  Stores like that are flooded with discontinued or surplus products taken off the shelf at other stores and sold at the dollar store for deep discounts.  After removing the plastic insulator from the battery terminal, allowing the battery to be connected to the path light circuit, I stuck the thing in the ground in a sunny part of my front lawn.  I let the light absorb some sunlight all day.....

story con't on page 5    

Off-Grid Home with Electric Car

A while back I got an email from a guy who lives in a nice house high in the Colorado Mountains using an off-grid power system.  He was planning on buying a plug-in hybrid car.  He wondered how many more solar panels he would have to add to his system to keep his car charged up without ever burning a drop of gasoline.  He said .....

story con't on page 2 

March 2011     Issue 15

Page 1 Back
Good Idea
gone Badly
New Products What the World
needs Now
Wily Widget

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

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