Sunday, February 22, 2015

Thorfire LED BULB REVIEW

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

DIY PCB DRILL

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.


Sunday, February 1, 2015

Filament LED: Silicon on Sapphire?

A while back I tore down what is still probably the most innovated LED light bulb I have seen.  Called a "filament LED" the LEDs appear to be arranged in a long series row on a glass like substance.

I did an acid de-cap to remove the phosphor.  The LEDs appear to have been grown on a sapphire backing... makes sense as it would not be economic to place so many individual LED dies on a substrate.

From what I can tell this appears to be Silicon on Sapphire.


Thursday, January 29, 2015

DIY Macro Mode for a Seek Thermal Camera

The Seek thermal camera is a nice bit of kit... however it's lens is fixed and focuses at about 10-15 feet.  Great for home inspection, not so good for electronics circuit board inspection.

A new lens, a selfie stick, and a bit of camera gear I already had results in a stable platform on which to record temperature of very small items indeed.


Saturday, January 24, 2015

Bell+Howell "Ultrabulb": reverse engineering and industrial intelligence

This bulb was heavily marketed on late night infomercials.  It's interesting to sort down who actually made this bulb and then to study the board to determine the process engineering.  One can easily visualize the manufacturing plant setup.


Saturday, January 17, 2015

DIY RF PREAMP AND NEAR FIELD PROBE

A few months ago one of my viewers was asking about radiated emissions from LED light bulbs... he was experiencing interference with his garage door opener and some new LED light bulbs.

It was an interesting question, however I did not have all the bits to test such a question.

For this task one needs a spectrum analyzer with a RF pre-amp and a near field probe.  RF pre-amps and probes can easily run into the $1000's.... which is a bit much for me!

A while back I found an off-brand amplifier and I was hoping that it might work... the construction, however, was far from ideal.

After a long and circuitous route I think I have a working probe... with my knowledge gained it would have cost about $10.00 to make (the commercial pre-amp I bought was $70.00.... only to extract a $0.15 part from it and to throw the rest into my junk bin!).

Video below:


Sunday, January 11, 2015

SUPER CHEAP PCB HOLDER: THE BAKU BK-687

The nice thing about ebay is the ability to get obscure tools at dirt cheap prices.

If you have ever tried soldering surface mount components to a circuit board you soon learn that you need to tape or hold the board down somehow to avoid chasing it across the desk.

I was getting tired of trying to use some tape or a heavy tool to hold the board.

A quick ebay search showed this tool. I am finding it most useful.

Look closely at the listings..... some are metal and some, I think, are plastic.  The metal one, I suspect, would be more useful at it has more mass and will not be affected by hot solder, hot air, or misplaced soldering tips!