LED Anchor Light Redux

[Lou Ostendorff]

Hello;
This message is intended for those prone to (infected with)'homemade- itis' and with a bent towards electrical engineering (Larry)...can somebody design for us a cheap LED cluster replacement for our existing 12v anchor lights? The Deep Creek light is nice but rather pricey at $150 each and I think the individual white LEDs can be had for about $3-$4 each (Radio Shack, Digikey, etc). Seems like all that needs to be done is to figure out how to connect enough of them together to get the correct voltage drop and current across each one...is this a worthy challenge for some gifted mind? We could all use a little less battery drain at night. TIA
Lou Ostendorff
CD25D, "Karma"
'82, #63



louosten@ipass.net

[Patrick Turner]

The Deep Creek design is expensive. It seems to be more then just a post with a bunch of LED's glued on tho'. It is incased in a bulb just like a normal tungsten element and has built into it a light sensitive diode that turns it on and off with the rising and setting of the sun. I'm pretty sure it's hand assembled which might account for some of the cost. It should (in theory) last you many years of use. Over the long haul that might save you a few trips up the mast and/or the cost of several replacement bulbs and possibly a few $$ worth of amp hours. It is kind of hard to justify and time will tell I guess. I installed one just over the winter and will get a reality check on the thing this season.

Pat



patrick.t@home.com

[Ken Coit]

OK,

Who will be the first to roll your own? Prices and specs for individual LEDs and assemblies can be found at the site below. A 12-LED assembly runs around $70 and 12 loose bulbs around $34. Highest angle of directivity is 50 degrees, so they pretty much have to be mounted in a horizontal circular configuration.

Let me know if someone gets a replacement bulb array together.

Ken

Hello;
This message is intended for those prone to (infected with)'homemade- itis' and with a bent towards electrical engineering (Larry)...can somebody design for us a cheap LED cluster replacement for our existing 12v anchor lights? The Deep Creek light is nice but rather pricey at $150 each and I think the individual white LEDs can be had for about $3-$4 each (Radio Shack, Digikey, etc). Seems like all that needs to be done is to figure out how to connect enough of them together to get the correct voltage drop and current across each one...is this a worthy challenge for some gifted mind? We could all use a little less battery drain at night. TIA
Lou Ostendorff
CD25D, "Karma"
'82, #63

PPPparfait@nc.rr.com

[Bob Loewenstein]

Who will be the first to roll your own?

I looked into rolling my own 2 yrs ago. The best price I found for a single high intensity white LED was ~$6. At the time I was looking at making my own clusters to replace interior lights and figured if I were in the market, it would have been cheaper to purchase the assembled unit from WM.

Ken's link indicates how much prices have dropped. Just looking in the Allied catalog, for instance, I find a 4 LED white cluster in a bayonet base (197-not sure whether that is the same as typical dome/spot lamps we use) is now between $8-$11. I also have found a signal stack light which is basically a set of 6 LEDs installed around a cylinder at 60 degree increments. This could be useful in a home brew anchor light. Cost $25. However, these require 24V minimum.

[Darin Bartram]

I'm not electrically inclined, but have you considered a ready-made Mini-Amp Mega Light? It advertises a very low draw.

Hello;
This message is intended for those prone to (infected with)'homemade- itis' and with a bent towards electrical engineering (Larry)...can somebody design for us a cheap LED cluster replacement for our existing 12v anchor lights? The Deep Creek light is nice but rather pricey at $150 each and I think the individual white LEDs can be had for about $3-$4 each (Radio Shack, Digikey, etc). Seems like all that needs to be done is to figure out how to connect enough of them together to get the correct voltage drop and current across each one...is this a worthy challenge for some gifted mind? We could all use a little less battery drain at night. TIA
Lou Ostendorff
CD25D, "Karma"
'82, #63

dbartram@bakerlaw.com

[R. Hoffman - Deep Creek D]

The Deep Creek design is expensive. It seems to be more then just a post with a bunch of LED's glued on tho'. It is incased in a bulb just like a normal tungsten element and has built into it a light sensitive diode that turns it on and off with the rising and setting of the sun. I'm pretty sure it's hand assembled which might account for some of the cost. It should (in theory) last you many years of use. Over the long haul that might save you a few trips up the mast and/or the cost of several replacement bulbs and possibly a few $$ worth of amp hours. It is kind of hard to justify and time will tell I guess.

____________________________________________________________________

Having been invited aboard by Pat, I really don't have too much to add to your on-going and past discussions of our LED anchor light. Yes, they are currently "hand-made" in our own shop...as opposed to being built in Mexico or the Far East. The way we build them certainly does affect the cost and we are currently working with a larger contract manufacturer to get them into a more "mainstream" and lower cost arena. Before we did that, we wanted to make sure that what we began to "mass-produce" would meet the current "official" certification tests for a "two-mile" light. In working with a certified testing facility, we have determined that it will take an array of 18 leds to reliably produce the stated candela output to do that...given the current led technology. There are other certification parameters to meet as well; such as projected beam angle, lack of sector nulls and even having leds that fall into the correct chromaticity (color) envelope...so there is a bit more to it than buying some surplus "white" LEDS and powering them with a simple resistive circuit that will soon "go south" in a marine environment.

In fact, our experience in building custom navigation lights for "PlayStation", "Pyewacket" and many other ocean racers has shown us that it's an absoulte requirement to protect that expensive LED array with driver circuitry to assure that the LEDs can deliver not only their full-rated light output...but continue to do it, so that the higher initial cost can be justified both by energy savings AND longevity in service. Our units typically use less than 10% of the electrical energy of the incandescent units they replace and can last 100,000 hours...compared to the 2,000-5,000 hours of a normal incandescent bulb. If you "value" a trip up the mast at more than $7.50 (round trip, of course, {grin}), and even not counting the cost of each replacement "normal" bulb...we might begin to look like a bargain.

One advantage to our pulse-driver that has not been mentioned has to do with human perception...in that there have been a number of studies that indicate that a pulsed (pulsing so fast that it "appears" to be continuously "on" to a human observer) on-off light source is perceived as "brighter" to a human observer than a non-pulsed light source of the same measured intensity in candela. This visibility phenomena is a beneficial adjunct to the voltage control and other protective and stability functions that our variable pulse width "driver" provide to our units.

Yes, all this is completely self-contained and "potted" inside our units (along with effective RF supression) and allow us to offer a 5 year warranty on these units. We want you to get good value both in energy savings, lack of bulb replacement hassles and automatic operation in a true "two-mile" light...which the original Davis Mini-Mega light is not. Go to our web site (www.deepcreekdesign.com) and look at the dusk photo there that shows a "certified" 10 watt incandescent bulb, our FirstStar units and a Davis unit all in the same photo...and you be the judge!

The arguments pro and con about energy use and conservation aboard seem to me to come down more to a "lifestyle" choice than anything else. Most any form of boating is "expensive" (certainly a relative term), but we happily pay the toll to be on the water...however we get there and whatever we do there. Sure, there are many options to be safely seen in an anchorage or underway and many new technologies to take aboard to enhance our enjoyment and safety. The choices for the individual boater are many and varied depending on individual preferences and individual budgets.

While we don't make kerosene lamps to hang in the fore-triangle, we admire and respect the "traditionalists" who still do. The choice of what equipment you use and how you justify those choices is yours alone. I think what we sell is certainly the "Rolex" of anchor lights. That's what we choose to make and sell to those who want more than a "Timex"...but you can buy either one!

Fair winds!

Rob Hoffman
President, Deep Creek Design, Inc.
S/V SUNDOG



briteled@mindspring.com