LED Light Hub

Just to be clear, are you looking to duplicate the WS Light Hub and just want to save some money by rolling-your-own?  Or are you looking for compatibility with the WS LEDs?  Or do you have a better mousetrap in mind and if so what features/capabilities are you after?

From a previous OGR thread:

Looks pretty easy to just sketch the diagram and clone it.

Yes, I want to "roll my own" hub rather than buy another one from W-S.

If you already have one, what stops you from duplicating what's in there?  Do you need help identifying components, finding sources for parts, etc.? 

Do you have a digital meter that you can make measurements?

If you want one or two, I'd just buy them from Woodland Scenics, there will be significant effort in "rolling your own".  Specifically, what are you trying to accomplish by building them yourself?  Clearly, by the time you assemble all the components and build it, you'll have more invested than buying them already complete.  Unless you are adding some unavailable feature, I'm not sure what you accomplish by building these.

Thanks for the advice...I already have one W-S hub and like it . I will pick up another one. I get LED's from a local electronics store, they work great with the W-S-H. Just not sure how many LED's can be powered from one hub, which was the reason I considered building another on my own.

$15 for a light hub seems reasonable.  OTOH some of their "connectored" LED prices seem a bit high so it sounds like you found a way to buy your own discrete LEDs.  Are you splicing their extension cables to get the connector?  Or if you found the mating plug what is the part number?  I recall this discussion from another OGR thread but don't think the actual plug (to roll your own connectored-LEDs) was identified with a where-to-buy...

To your point about power capability, it appears you plug in, say, 16V AC accessory voltage and this is reduced to the ~3V LED voltage by resistors.  That's a rather anemic efficiency of less than 20%.   While moot if you're just going to buy another Light Hub, but if your were to roll-your-own, one idea would be to insert a 99 cent eBay voltage converter module to for efficiently reduce the voltage.  This could, say, triple efficiency meaning you could light up 3 times as many LEDs for the same amount of power.  The typical LED draws, say, 0.020 Amps.  A typically Accessory Transformer might put out, say, 3 Amps.  So that's 150 LEDs using dozens of Light Hubs so I don't think this was a major concern.

Another roll-your-own enhancement would be compatibility with 12V LED strips.  So toss in a few "hi-power" outputs with brightness control that drive one or more sections of LED strips for larger buildings or station platforms.

A better set of measurements of the PCB header and plug, not to mention pictures, could doubtless identify the connector type.  I'd be willing to bet it's a fairly common connector that can be had for peanuts.

Bet you thought this thread was dead, in my web search, it came right up.  Can any of the previous posters tell me if this will work.  I just bought the really nice looking Woodland Scenics Water Tower in O scale with LED light but I want to use it on my outdoor G scale layout with all my building lights powered by a 18v DC landscape lighting transformer.  Question: can I just wire the building LED to my 18v DC circuit?  Will that burn out the LED?  The Power Supply for the WS Lighting Hub that they recommend say it's output is 24v DC to the Hub.  I want to avoid the Hub, would rather use resistors if I need to.  Thoughts?

Also, Vegastrains, I see you are in Henderson in my zip code, maybe we could meet and talk trains, I am always looking for train pals.  Email in profile.

Chris S.

Right.  The Light Hub is essentially a variable resistor.  It does have AC-to-DC conversion but you don't need that if you already have DC.  So a single 5-cent resistor should do the trick.  If I'm looking at the right accessory, WS site says the Water Tower is a 30mA LED.  So if this is a white LED, you'd need a resistor of, say, 510 Ohms to drop the 18V DC to about 3.3V DC.  That is, Resistance = Voltage drop / Current: (18V - 3.3V) / 30 mA = 490 Ohm. 

So 510 Ohms would be a closest "standard" value.  That's such a large voltage drop that the resistor burns about 1/2 Watt so you'd want to use a 1 Watt resistor.  But practically speaking, it's so much easier and less expensive to find 1/4W or 1/2W resistors so you could use a combination of lower power resistors.  More info about this if vague.

Thanks Stan, that is exactly the information I needed.  I am trying to take the simplest route as almost all my outdoor buildings, bridges and elevated trackage is lit with the 18v DC landscape lighting, easy, super durable outdoors and cheap.  Every once in a while I have to integrate some single small LEDs.  If the LED is red will that make much of a difference?

Chris S. 

Red LED's light around 1.5V-1.8V, so you'd want a little more resistance.  I find it odd that they have a 30ma LED, that's hardly a standard value, I wonder if that's an error in their specifications?

Gunrunnerjohn, yes I thought so too, most I see are 20ma.

Chris S.