Top Electricians in Clackamas, OR 97015

Bret Bowman and the All Natural Landscape team did a fabulous job on our landscape renovation. They were very responsive from the first meeting until the completion of our project. I would recommen...Read More…
Some cool decrotive piece for your livingroom? Or GREAT dishes for your kitchen? Look no further you have found the right place!!They have everything here from fruniture to wine!Lots of imported it...Read More…

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All Natural Landscape

5.0

By Anonymous

Bret Bowman and the All Natural Landscape team did a fabulous job on our landscape renovation. They were very responsive from the first meeting until the completion of our project. I would recommend them to anyone that needs any landscaping design or implementation help. ...read more

Cost Plus World Market

1.0

By pdxhhgirl at Citysearch

I was accused of shoplifting during Christmas time in front of a ton of people when I absolutely did not shoplift! I, in fact have never stolen anything in my life.They can not do that! It was the most horrible, humiliating, slanderous thing that has ever happened to me. I am boycotting this store until I receive some sort of apology from corporate. Its really too bad because I enjoyed shopping there..great selection and prices. Advise: Don't bring in shopping bags from other stores and don't be bundled up, even if it's 10 degrees outside! They might target you as a criminal and publicly humiliate you! ...read more

Cost Plus World Market

3.0

By Robin W. at Judy'sBook

Some cool decrotive piece for your livingroom? Or GREAT dishes for your kitchen? Look no further you have found the right place!!They have everything here from fruniture to wine!Lots of imported items! Imported art to imported candy!They al... ...read more

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Why not buy the cheap LED Christmas lights?

     LED lights require a DC voltage to operate. How you get the DC makes all the difference in the world.  To better understand this, we need to have a basic understanding of what rectifier and diodes are.  A rectifier is a device that simply converts alternating current (AC) into direct current (DC).  Alternating current is current that flows one direction in a circuit on the first half of a sine wave and then the opposite direction on the second half.  If we use a frequency of 60 Hz. (cycles per second) then the direction of current changes 120 times in one second.  DC will always flow the same direction in a circuit.   The way a rectifier changes AC to DC is by the use of a diode, or multiple diodes.  Diodes only allow electrons to flow in one direction through them. When the voltage on the anode is more positive than the voltage on the cathode, current will flow through the diode.  If the voltage is reversed, making the cathode more positive, then current will not flow through the diode.  (unless the peak reverse voltage rating is exceeded). In the drawing below a single diode is used to rectify the alternating current.  A half-wave DC output is produced. On the first half of the cycle the diode allows the electrons to flow through it powering the DC load.  On the second half cycle the diode blocks the flow of electrons and the load receives no flow at all.  This is what causes the flicker effect of cheap LED lights. When we use a four diode bridge rectifier , we solve the problem of having no flow to the load for half of the time. On the first half of our cycle the flow electrons passes through the bridge allowing electrons to flow to the load in one direction.  Then on the second half of the cycle the flows passes through the bridge recifier following a different path, but still sends the electron flow in the same direction to the load giving it twice the output of a single diode rectifier.  In the animation above, the cycles are moving at 1/16 cycle per second, while in actuality, this is happening 960 times faster at 60 cycles per second.  An RC filter (a resistor and a capacitor wired in parallel with the DC load) further smooths the output reducing the flicker even more.  So to answer our original question, LED Christmas lights that make use of full-wave bridge rectifier technology are worth spending  a little more for.   ...read more

By The LED Thing May 02, 2010

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Wall lights add a beautiful and delicate decorative touch to homes. Homeowners who would love to add a great ambiance to their home may be interested in getting interior wall lights installed. Here are some instructions on installing these particular wall lights for your home. ...read more