Wanting to add LED's to club layout.

I would suggest a 12 vdc power supply and a reel of leds. 300 leds that can be cut in multiples of three, such as ebay #283363732897, for about $8. A used computer power supply can be had for $10 to $15, and will power hundreds of lights

Jeff, 

I also would recommend the reel LEDs from eBay, but with that l would consider the buck converters that you will find there also. That way once you have the LEDs installed the power source of the layout can be tapped to power the LEDs, one less thing to hook up at set up.

Ray

Jeff, here are some examples of what John and Ray are talking about.

photos

1. The buck converters:  LM2596 AC/DC to DC and/or DC to DC.  (Many of these can be sourced that don’t require soldering).

2. The application voltage from xfrmr to stepdown converter to buss, and further stepdown to some buildings requiring different voltage.

3. Diagram of current travel; follow from right to left.

4. The old PC power supply, this one was free from my old computer.

5. A 12VDC/30 Amp commercial power supply from the bay. ~$20

Hope this is helpful.

This was from another post I made answer to a similar question:

At under a 2.5 amp limit, the buck converters are the answer. So not for locomotives or even trolleys.  The converters allow you to set each building or accessory based on its needed voltage and current requirements.  I have bought 8, and one shorted out (now in the landfill).  At $ 2.70 who cares?

Buy 4 or 5 (spend less than $15 and wait 3-4 weeks) and set one each up to:

1. output DC 1.5 v (for, say incandescent streetlights)

2. one at 3v (for say a Menards building that is supposed to have 4.5 v- but is too bright)

3. one at 8v for some other LED lighting, and

4. one at full-tilt boogie 12+ volts DC (or run the higher-voltage accessories using AC off your bus).

This what I have done- I use 7 Buck Converters mounted under the layout to boards, and that allows me to use:

1 -for 16 cheap (Menards- $ 4.99/ pair Sku # 2897620 Lemax incandescent streetlights- rated for 3v) running at 1.5 DC for longevity

2 - Menard's York Hotel- (it has its own buck converter since it draws about 2.5 amps), running at about 3v to keep it at lower lumens- it is BRIGHT!!

3 - running 12v DC rated Todd Architectural Stauffer's Biscuit building (at 8.5 v.) again to control brightness

4 - Several 4.5 v DC rated Menard's buildings at 3 V DC of the recommended 4.5 v. also so they are more realistic.

There are also converters that have digital voltage readouts w/ knob adjustment:

e-Bay No. 173806650164

This one is the least expensive one I could find (that has - important!- DC output as low as 1.25 v., and has a heat sink).  IMO these are features I would recommend.  BUT- in my experience, once you set them they stay at the set output.

The buck converters will only be used on accessories that can use DC- and you see that all of mine are related to lighting. 

Each converter can output based on available voltage- so- the more of these running off the same input bus, you might not be able to set their outputs at high enough levels.  When the highest output one won't get where you need it- jack up the transformer (the stepdown bucks will still limit output at their set levels).  Or, you might want the main bus running at near full available voltage off the transformer.