One thing I had to do prior to packing for the exhibition was to install a decoder and LEDs into one of my locomotives. Having read the various threads (Keith's thread is beneficial : http://www.platform1mrc.com/view_topic.php?id=652&forum_id=15), I had a go my self... I had a few DCC Concepts DCC-S2SAP-5 spare, so I used this, but had to purchase a few LEDs and some resistors. Keith recommended inhis post using a 1K 0.25W resistor, but I had to opt for 1K 0.5W resistors... The difference is the brightness I believe, correct me if I'm wrong... Above. The DCC Concepts decoder has Stay Alive to which I am not using. Below. The LEDs and resistors. (I purchased 10 x LEDs and two x 8 packs of resistors as I have another loco to fit out.) Carefully left up the plug to reveal the analogue circuit board. Release the screws and remove this board. Do not throw away as it can be used in another locomotive if necessary. Starting on the front (short hood end), I removed the plastic cap that holds the yellow wire (negative) to the decoder socket. A new length of yellow wire was threaded through the hole in the connector and the cap was replaced. For the blue wire (positive), I cut it from the bulb and soldered a resistor to this. I chose to shorten the length of the resistor prongs to help fit back in the small space. The legs (cathode : negative and anode : positive) were also shortened, with the positive kept slightly longer than the negative. The resistor was then soldered to the positive leg, followed by the yellow wire. This pic is the long hood end of the loco showing the resistor soldered to both the blue wire and the LED. The white wire here is the negative. As you can see, where I could get heat shrink onto the wiring, I did. Where I couldn't, I wrapped a small piece of electrical tape around the join to insulate. Next step is to install the decoder. Make sure the decoder is positioned the correct way. I done this by looking at the decoder socket on the loco and sighting the black & grey wires. Push fit the decoder and now test before placing the body back on. Above and below. First I wanted to test to see if the LEDs worked, which they do ! I then checked for forward and reverse movement. All good. Now it's time to carefully replace the body after securing the wires inside with some extra electrical tape. Once done, test again... Yep, they certainly are bright... I wanted warm white LEDs but could only get cool white. Oh well, beggars can't be choosers if you need a quick fix... There we have it, all good to go. Now I just need to weather her a little... Cheers, Gary.
Nice one Gary. Re the lights, you can dim them a little using cv's, or change the resisitor to a high value, possible a 50K. To dim the lights go to the test track set up and the change cv section. front light (white wire) is cv 49, enter 12Rear light (yellow wire) is cv 50 enter 12 this will dim the lights, possible enough, but if not then a bigger resistor is the only way. This might be of help to you and other if you want to get the most out of your lighting features with dcc. Just enter the light cv number above, ie cv 50 Yellow then enter the value in the box...have a play with them there are some great effects. Kim
Nicely done Gary The 0.25W & 0.5W is to do with the power they can handle, so for you the main difference is size. You can also dim them by increasing the resistor value, or have two in series. The CV route works by switching the LED rapidly off and on, both methods work equally well, but the CV method may give strobing or flicker when making videos Paul
This might help give you an idea of what the different resistor values can have on a single LED. shown are 1k, 10k, 30k, and 50k with proto-white (warm white) but the drop in light value will be the same for bright white LED's Kim
Nice demo Kim For photos the 50K probably looks best, but is probably best tried on the layout to see which gives the best impression. Paul
Yes I would agree Paul, infact the 3 mm LED's only really look their best when viewed from the front. All four. 1K and 10k still to bright for my taste I've removed the 1K, for me, like you Paul the 50K would be the best option BTY...12volts and no room lights on for these last two pictures Kim
Thanks Kim and Paul, very informative. I'll source some 30K & 50K resistors after the show. Cheers, Gary.
Y'see, it's easy enough Gary, you just have to jump in, and you'll be 'over to the Dark Side' before you know it!!! You could try a coat of yellow paint on the LED to take the edge off the whiteness of the LED and make it more like an incandescent lamp. Keith.
That would be an easy fix, but the loco is on shed at Thornleigh (exhibition hall !)... Cheers, Gary.
Looking at the bare chassis, substantial motor and what I assume are weights, is there any internal cab detail, or in fact any room left for cab detail? I tend to fit cab lights where possible, but if there is no internal detail (as for example, one end of the Lima class 33's, where the motor makes this impossible) then there's no point. Keith.