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Let's drop in on Wily and
look over his shoulder at his latest project.... |
Water
Well Pump Motor Indicator |
One of
Wily’s neighbors stopped by and described a problem he was having with his
water well pump. The guy needed Wily’s help. He wanted a simple
way to know when the submersible pump motor was turned on and running, so
the neighbor could do some troubleshooting. The water well head and
electrical connections were located some distance from the back of the
neighbor’s house, inside a small shed. What the neighbor wanted to do
was turn on a small light whenever the pump turned on.
He wanted the light to
be bright enough so it would be visible from the house. He was not
sure, but the neighbor thought that the pump motor was turned on and off by
switches deep down the well. Therefore, there was not a simple
switched voltage to tap into at ground level in the shed. How could he turn
on a light when the pump was running? Wily thought about it for a few
seconds and then told the neighbor that he thought he had a solution..... |
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Wily Widget,
the Lone Inventor
with Gadget & Gizmo |
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WHAT
THE WORLD NEEDS NOW is a....Bovine Calving Alarm |
This
request came to me by way of a dairy farmer in Minnesota. He has a
large number of milk cows and breeds them. He said he lost a few cows
because they had trouble giving birth in the middle of the night. What
could be done to help him? .... |
story
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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.
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High Voltage Ceramic Capacitors for Line Powered LEDs
By: David Johnson
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Many AC line powered DC supplies for LEDs wired in long series strings use a
series connected capacitor to limit the current drawn from the power line.
Typically, these capacitors are Mylar or polyester film devices.
However, I think that much smaller ceramic type capacitors might also work.
Below is a photo showing a pair of capacitors each with the same 0.47uF 250v
rating. Clearly the ceramic device is much smaller..... |
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Temperature Sensitive MOSFET
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A while
back I was asked by a company to look into why one of their products failed to
operate properly in cold temperatures. A simplified version of the
circuit is shown below. Two n-channel MOSFETs and a few resistors are wired to
form a flip/flop latch circuit. Each time the pushbutton switch is
pressed,
...... |
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Bad 40W Fluorescent Lamps |
Is it just
me, or are standard 48 inch 40W florescent lamps dying much faster these days?
I remember when these things would last 3 years or more. Now, I’m
replacing them more like every 6 months. Some don’t even last one month.
When I moved into my current house some 12 years ago, I installed a number of
fluorescent lamp fixtures on the ceiling of the garage. The fixtures
hold two standard 40 watt, 48 inch cool white lamps..... |
story con't on page 5
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Charge Pump
Paradox
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Below is a pretty simple circuit. At first
blush it seems fairly logical. It was conceived by a
Discover Circuits visitor. He thought the circuit would
allow the low voltage from a single solar cell to charge a large
super capacitor to a much higher voltage using a charge pump
method. But, would this circuit work?.... |
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