Tuesday, April 14, 2015

Solais LR30 LED Bulb Teardown: Quality

An interesting bulb which is targeted to a much higher end market.... refreshing change after looking at all of those bulbs chasing the lowest possible initial price.

I should buy a non-fanned LR30 from a big-box store and see what the led temp rise difference is... I suspect it's huge.  One can move an amazing amount of energy with even a small fan.

Tuesday, April 7, 2015

Joule Meter: Precise Energy Measurements of an Electronic Circuit

I needed to measure the exact energy draw of a circuit.  Since energy is measured in Joules, a joule meter.

I could not find anything quite like this in the market... the closest I could find were some watt-hour meters but they still had very poor resolution.

So I made my own.  Arduino based with some custom circuits.  Video, below.  Sketch used on the arduino below that:

Monday, March 9, 2015

Philips "Warm Glow" LED Bulb: Tune able Color Temperature

One of the drawbacks of an LED is that it will produce the exact same color (measured in Kelvins) at all brightness levels .... problematic when one desires a warmer, more cozy dimmed light.

This bulb brims with innovation to create that effect.  A very neat bit of engineering!

Sunday, March 8, 2015

LEDs, Temperature, Reliability

So I was looking at a bulb with just a terrible warranty and I was wondering if the design is so fundamentally flawed that the LEDs run too hot for good service life, or if the warranty is just super-short to allow the lowest possible sell price.  I collected a data point to help better understand the issue.

Saturday, February 28, 2015

Philips Slim Style '75w' LED Bulb Teardown

Very similar to the 60W version.  Most of the same draw backs remain... I presume there has been trade off on manufacturing costs versus undesirable features.

Sunday, February 22, 2015


From amazon.com.  Neither CSA nor UL approved.  Bad Chinglish on the box.

What caught my eye, however, is the large finned heat sink.  I was wondering if that would translate into a lower operating temperature.

It seems, however, that although it draws 12W, the same as a old Philips bulb, and claims 1100 lm, 300 more than the philips... it runs rather hotter.  I am also not convinced that it's producing considerably more light than the Philips bulb.

Sunday, February 15, 2015


If one makes their own circuit board the need to drill really small holes is important... normally done with a very small and precise drill press at ~$300.

Lots of ebay vendors, however, are willing to sell a small toy dc motor, collet, and some drill bits.... it's an interesting starting point to building one's own.   The use of a toy motor is both genius (so cheap) and silly (the bearings in such a motor are far from precision... and they are really not designed to take vertical loads).

The natural inclination to use this bit of kit would be to turn to my metal lathe and use the milling adapter to whip up a suitable fixture... however I would assume that if one is in the market for $5.99 "drill press", that would be an unlikely tool to have in the workshop.

I instead approach this using only simpler and more likely available tools.

The use of a copper plumbing pipe and union provided an ok-ish linear slide (even with polishing, however, it's not a smooth as I would like).  The off-center spring also is not quite as good as the spring-around-the-pipe that I planned... however getting spring wire to form my own spring (quite a simple task) was not possible as I could not find any of that wire locally.