I found some soda straws that are thin and about the same color blue as the blue LEDs I got from goldmine-elec.com. I got the idea of using a soda straw from Quantsuff at quantsuff.com. He used two white LEDs in the ends of a short length of white translucent (semitransparent) soda straw to give
(Read More…)
I received a bag of 200 blue LEDS in milk white packages from Goldmine-elec. These put out a diffused blue light that has a wide beam pattern. I’ve been thinking about colored LEDs, and I’ve come to the conclusion that the colored LEDs I use don’t need to be in a clear case and the
(Read More…)
I ordered these from an Amazon seller, Liroyal-led, a few weeks ago in April. It took that long to ship from Hong Kong. They are 50 pcs of Bluecell 5mm RGB full multicolor flashing LEDs. The cost was $3.45 including free shipping. The case is clear epoxy. I looked down inside and saw four chips
(Read More…)
I received my package of LED’s in the mail today from goldmine-elec.com. Quantsuff emailed a link to their sale on the Nichia NSPB633 blue oval LED (it might say NPSB, but that’s a typo). They are on sale for 100 for $10. I ordered some and I have been playing around, err, experimenting with them
(Read More…)
I took apart a “Type R” LED light, which is a substitute for a wedge base auto light used in instrument panels and dome lights. This light has an 8 mm diameter LED and a 560 ohm, 1/8 watt resistor in the wedge base. Assuming that the LED drops 3.2 volts and the auto’s battery
(Read More…)
One Joule Thief I have not built (at least not in the same JT) is the low power JT with the CdS photocell. Almost all of my JTs with daylight shutoff used a LED as a light sensing diode, and then most were flashers. I have a bunch of CdS photocells but I haven’t really
(Read More…)
Paul discussed buying LEDs and I decided to write about some of my experiences with buying LEDs in this blog. I bought some LED assortments from an eBay seller, I think he’s from Canada. He’s still selling stuff. Most of the LEDs had bubbles in them. I dealt with him through email, and I said
(Read More…)
I went to my computer club meeting this Sunday and they had a really good deal on the consignment table that I just couldn’t pass up: three 21 LED panels for five bucks apiece. They’re built very sturdy, with a body of extruded aluminum and screws holding the end covers in place. The ‘handles’ on
(Read More…)
The LED flashlights I bought in March from Amazon (but shipped from Hong Kong) arrived recently and I’ve had a chance to use them a bit. I paid $5.49 apiece, with free shipping, but I see that the price (as of June 8) has gone down to $4.30, These have a Cree Q5 emitter, and
(Read More…)
This is an old schematic that I drew in Apr of 2005 using SwitcherCAD III (now LTspice). It is taken from the board I built and put in service for several years as a LED test jig for testing the lifetimes of various white LEDs. Needless to say, most of the white LEDs lasted less
(Read More…)
