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  1. ncmrdispatcher

    3985 lighting

    Pre-wired SMT LEDs are available from ngineering.com, but they are proud ($) of their work! The same folks sell a little fixture to hold the LED while soldering. A friend and I stole their idea and came up with this. The LED goes in the middle clip. In this photo it is an 0603, which...
  2. ncmrdispatcher

    3985 lighting

    Blue - Correction: There seem to be at least two lamps on each side under the running board. In the first photo, there is a second lamp in the upper right corner. I don't have a great photo that shows the second lamp on the fireman's side, but in another photo shot a few seconds earlier...
  3. ncmrdispatcher

    3985 lighting

    Blue - Depending on the era, you would not see any firebox flicker from 3985. The locomotive was originally build coal-burning, so any flicker would be hidden by the grates and ash pan. It wasn't until well after 3985 was rehabilitated, after being stuffed and mounted for years, that she was...
  4. ncmrdispatcher

    flux paste for soldering flex track

    Mike - Acid flux, containing zinc or ammonium chloride, should never be used on stranded wire. The flux will flow beneath the insulation where it will slowly rot the wire. After creeping under the insulation, it is impossible to wash off. Here's what a common zinc chloride flux, Tix brand...
  5. ncmrdispatcher

    How many amps?

    How many do you want to run simultaneously? Certainly not all 21! Those that are moving are the only ones that matter. All the others draw an insignificant amount of current when just sitting there idling, even if they are making noise. When I was doing some HO decoder installs a typical...
  6. ncmrdispatcher

    2 rail or 3 rail?

    Y3a - You can read about one fellow's approach to O-scale 2-rail on David Stewart's Appalachian & Ohio web site. This is a large layout that is far more ambitious than most. All track is hand-laid, which is something that David particularly enjoys. Turnouts from #6 to #13 are built in-place...
  7. ncmrdispatcher

    Atlas 2 rail box cars

    Two thumbs up! Great job.
  8. ncmrdispatcher

    LED's and variable voltage

    Doug - Always use a series resistor with each LED. Unlike a regular light bulb, they do not appreciate being driven by a fixed voltage because the current will vary wildly with tiny changes in applied voltage. It is very easy to exceed the maximum current rating, typically about 20 mA...
  9. ncmrdispatcher

    LEDs from variable DC?

    Bernie - Mark G. offered the simplest solution: just put a 1K ohm resistor (or thereabouts) in series with the LED. An LED tries to limit the voltage applied to it by exponentially increasing the current through it until it melts, sort of like a water tank that starts to overflow (water depth =...
  10. ncmrdispatcher

    DCC purchase

    I have purchased goods from Tony's for many years, and I have been extremely pleased with his service and support. I can't say whether Tony's is the least expensive vendor, though his prices seem quite good. No relationship other than as a completely satisfied customer.
  11. ncmrdispatcher

    Front and Rear Ditch Lights

    In larger scales (I'm in O 2-rail) we often require a pair of decoders with both set to the same address. Here are two common alternatives for doing the decoder programming: PROGRAM BEFORE INSTALL Install one decoder and program it. Prior to installation, program the second decoder. However...
  12. ncmrdispatcher

    Richmond surface mount LED

    Most DCC systems I've seen require about a 14 to 16 volt AC transformer as does my NCE Powerhouse Pro. The requirements will be spelled-out in the owner's manual. A 12 volt transformer will lower the track voltage a bit; whether that is a problem is for you to decide. A 12 volt DC supply will...
  13. ncmrdispatcher

    Richmond surface mount LED

    Jim - I'm sorry my answer did not seem entirely clear. Short answers: The Tsunami provides between 12 and 13 volts at a function output, which can vary a bit depending on the particular DCC system you use. The usual (99% of the time) output voltage of any decoder lighting function is 12-13...
  14. ncmrdispatcher

    Richmond surface mount LED

    Short answer: A 1.5K ohm 1/4 or 1/8 watt resistor per LED produces an intense light with a lot of safety margin in virtually every situation. With larger LEDS (3mm diameter and above) a 1K 1/4 watt can be considered a universal solution. Long answer: An LED wants to be driven by a...
  15. ncmrdispatcher

    Light bulb (LB) / LED What are their characteristics?

    Ken - I use lots of LEDs -- 16 each in O-scale 2-rail GP9s I'm building. These are both 3mm and surface mount (SMT) parts. LED LEDs want to be powered by DC current provided through a series dropping resistor. In 90% of my DCC LED installs, I use a 1K ohm resistor when powering the LED...
  16. ncmrdispatcher

    New Layout

    Sweet! Keep the photos coming!
  17. ncmrdispatcher

    P&D F unit kits

    Chris - Yes, David's A&O was featured in the May 2006 issue of Model Railroader. The locomotive described in this thread was the lead unit on the magazine cover.
  18. ncmrdispatcher

    P&D F unit kits

    Greg - The fabulous layout is the work of my friend, David Stewart. These (but not all) A&O F units are mine. More of his layout at: http://www.aorailroad.com
  19. ncmrdispatcher

    P&D F unit kits

    Here is one way to illuminate the number boards. With a little filing, a short piece of Evergreen rectangular styrene tubing will just fit inside the brass P&D number board castings. This replaces the kit's white plastic insert. A color-corrected white LED (illuminated in this photo)...
  20. ncmrdispatcher

    P&D F unit kits

    Yes, all-wheel pickup is a big help. The pickups are thin phosphor bronze, formed with pliers, applied to the back of every wheel. Both P&D and NWSL replacement wheels arrive with a dark, greasy coating that must be removed for good contact. I did this by wet sanding with 400 grit carbide...




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