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Third Quarter, 2012                                                                                                                                               Previous Issues     

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

Single Lead-Acid Cell Voltage Monitor

Wily was just finishing his morning cup of coffee when his phone range.  The caller was the owner of a large photovoltaic power system installation company.  They install ed systems for business owners and home owners who wanted a complete solar power system, using photovoltaic solar panels mounted on the roof of their home or building.  Most of the systems the company installed were grid tied, which do not use any storage batteries. But, sometimes, the company did install systems with a large battery for backup power and for off-grid systems.  The caller explained that the battery banks used large lead-acid cells to harvest the energy made in the daytime by the solar panels, so that energy could later be used at night.....

con't page 7

Wily Widget,
the Lone Inventor
 with Gadget & Gizmo

WHAT THE WORLD NEEDS NOW is a....Water Heater Flame Detector
A while back I got an email from a Discover Circuits visitor.  He had a house full of guests who all had to share one bathroom shower.  The small home’s water heater was not large, so it frequently ran out of hot water.  He wished there was a way he and his house guests could know when it was safe to take shower. ....
story con't on page 6
25 Watt-hour Battery Pack for Charging Devices through USB Port
By: Dave Johnson
My wife often forgets to plug her phone into its charger.  Later, the phone runs out of juice.  I thought it would be nice to have a compact battery pack which could conveniently fit in her purse and be switched on to charge not only her phone but any device which draws power from a USB port....

   story con't on page 4

Swapped Parts   

One of my old clients was still producing a product I had designed for them decades before.  Over the years, they had to make a few changes here and there.  Most of the changes were in response to some older parts which had become obsolete and had to be replaced with more readily available parts.  The company had just received a batch of new boards soldered by one of their suppliers.  None of the boards worked properly.  Over the years, they had never had any problems with the design or the boards so they were puzzled.  I told them to send me a few boards to look at.....

 story con't on page 3

Bad Bug Zapper
About 6 months ago, I purchased an electric bug zapper (“Stinger”, made by Kaz, Inc. in Southborough Massachusetts) for my shop.  Ugly flies buzzing around my head and biting my legs and arms while trying to work were driving me nuts so I thought this product would help knock down the fly population.  I figured I could leave it plugged in day and night and let it zap away.  It was a classic design with a high voltage screen grid inside a plastic case and an ultraviolet lamp, to attract the insects..  

story con't on page 5    

Email us and let us know what you would like to see in upcoming issues.  Thanks

Third Quarter, 2012    

Page 1 Circuit
Good Idea
gone Badly
What the World
needs Now
Wily Widget

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

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