On Thu, 15 Sep 2016 17:25:33 -0500, Don Foreman
wrote:
On Thu, 15 Sep 2016 14:43:13 -0700, Larry Jaques
wrote:
I'm guessing you found a good middle ground to illuminate the flag, or
did you use their driver?
Middle ground???
I used a molded plastic TIR (total internal reflection) optic with
12-degree beamwidth, produces a very crisp spot just big enough to
illuminate the whole flag from a distance of about 25 feet. I'm
driving it with a 5-volt wallwart ($1.50 surplus), in series with a
shop-made current regulator that regulates LED current to 700 mA. The
LED is rated for 1 amp but it's plenty bright at 700 mA and it runs
barely warm to the touch.
I thought maybe you fabbed up a driver, but I hadn't even considered
that you'd have to do optical work. Cool.
There's also a dark sensor in series that turns it on at dusk and off
at dawn. That was made with junkbox parts, including a cadmium
sulfide photosensor that was half a buck at the surplus store when I
got it some years ago.
Those only last a couple years, yeah? I've replaced quite a few
photosensors over the years in PIR lamp fixtures.
I found some adjustable-focus, 5-mode flashlights on eBay for $5 a
pop. They have Cree XM-L2 LEDs and are the brightest thing I've seen
for under $100. I loved it so much, I bought two more for myself, and
sets of them, including extra 16550 rechargeable batteries, chargers,
and cases, for my whole extended family for Christmas stocking
stuffers last year. Oh, modes are high, medium, low, flasher, and
SOS. Waterproof, too. They're made of decently heavy gauge aluminum
with crenellated face (good for self defense: smack the perp in the
forehead to blind him with his own blood while you run.)
http://tinyurl.com/hrpt9vy They're up to $7.43 now. What a deal!
The circuit before that was for the 3-watt "bugfree" LED light. It
lights up the whole deck for cleaning fish after dark, is visible from
across the lake 1.25 miles distant. It's a very narrow-spectrum amber
color that bugs can't see. This was Mark III. I gave Mark II to one
of my good neighbors at the lake.
Really? An amber bulb which doesn't draw insects? Amazing! Brand
and model, please! Or frequency, at least.
I used a Cree XP-E2, three LED's on one star mount.
http://www.ledsupply.com/leds/cree-x...power-led-star
It's coupled to a matching molded plastic triple optic, medium (35
degree) beamwidth. Color is amber, wavelength is 585 to595 nm.
It's housed in a machined aluminum cylinder 1.5" dia by 1" long, with
7 fins, looks like a large model aircraft engine cylinder. This one
is runnng almost 10 watts so it needs a decent heatsink. Email if
you'd like a photo.
Will do. I'd like to see it.
Here's a pair of 3w 6v COBs for $3.04 delivered. Hmmm...
http://tinyurl.com/godj4dz I wonder how they're heatsunk. Maybe buy
one of the $2 recessed fixtures with heatsink and replace the LED...
I need to work outside at night every once in awhile, and the bugs and
moths make it less than fun.
I bought a 10w 6500k white COB LED with metal tabs which can be
heatsunk through the tabs and the back of the chip mount with
compound. It has just been lying around, as I found love in the XM-L2
first. g
--
The goal to strive for is a poor government but a rich people.
--Andrew Johnson