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Issue 13,  November 2010- Page 1                                                                                               Previous Issues     
  

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

Restaurant Table Service Request Flasher

Wily was raking and bagging up some leaves from his back yard when he got a call from a restaurant owner in Lubbock Texas.  “Lubbock Louie’s” hamburgers was a popular place to eat in the Texas town. 

According to the owner, at times, the place could get quite busy and noisy.  The owner wanted to know if Wily had time to come up with a simple way to help his waiters know when someone at a table needed service. 

Wily gave the request some thought and after some negotiations, he agreed to take on the project....

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Wily Widget,
the Lone Inventor
 with Gadget & Gizmo

WHAT THE WORLD NEEDS NOW is a....
                                   Day/Night AC Power Switch with Hysteresis

I have several outside lights with built in day/night switches. The switch turns the light on at night and off during the day.  But, although small, the switch modules use simple a CdS photocell and a triac switch circuit. 

They almost always flutter the lamp at dawn and dusk.  This fluttering action is caused by the lack of hysteresis in the circuit.  When the CdS cell says that the light should turn on, the act of turning it on increases the light intensity. The photocell then says that it is not dark enough and turns the light off again.  This on/off cycle is repeated for perhaps 5 minutes twice each day until finally it is either dark or light enough....

story con't on page 6

Title
By: Dave Johnson  
                      
Not quite ready for publication, please check back

  story con't on page 8

New Products 2009
New product announcements are made nearly every day.  I subscribe to many trade journals and each is filled with hundreds of flashy advertisements.  But, only a few of those product ads catch my eye.  Since I’m a circuit designer, I especially like those components that trigger many new application ideas in my mind.  Sometimes it is the smallest products that are the most useful.  I often discovered new products in surplus electronic catalogs.  The surplus companies often buy up stock that came from companies that went out of business.  Bad marketing or bad management may have killed a perfectly good product idea.  Their loss can be your gain if you can spot the bargain.                               
Flameless LED Candle Power Boost
By: David Johnson
                                                                                                            
I got an email from a Discover Circuits visitor a while back.  He loved the new battery powered flickering yellow LED candles but he wanted something which was much brighter and powered by longer lasting alkaline D cells.  He wanted to make a light, shaped as a torch.  A plastic piece would be shaped to resemble the flame of a touch.  A flickering yellow LED light would give the illusion of a flame.....

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Conductive Adhesive Tape Problems       
Some 40 years ago, I was working for a well known electronics company in Colorado.  I was working on a new oscilloscope model, which had just been released from engineering for mass production.  The scope had a number of circuit boards.  Most used edge connectors similar to the photo below.  These gold plated contacts on the edge of the circuit board slid into a matching connector. ....

 story con't on page 3

Bad Carriage Bolts
A few months ago, I hired a handy man to make some repairs on my 15 year old wood deck, on the back side of my house.  He needed to strengthen some of the deck posts by securing them with new 1/2 inch diameter long carriage bolts.  He ran over to a local Lowes Hardware store, about a mile from house, and came back with a half dozen of the bolts with matching nuts and washers.  After a few minutes, I heard some swearing coming from the back yard.  I went out and talked the guy.  He got the nuts about half way screwed down onto the bolts but they would not go any farther.  He finally had to saw the nut off the bolt.  We looked at the bolts. ....


story con't on page 5    

Not quite ready for publication, please check back
 

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November 2010     Issue 13

Page 1 Back
Envelope
Circuit
Diagnosis
Experimenter's
Corner
Good Idea
gone Badly
New Products Rants &
Raves
What the World
needs Now
Wily Widget


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