I need some reassurance, for sure. I have installed many drop in decoders as well as several hard wired decoders and have had no problems but this is the new LS5 version that I have put into my Key/Athearn locomotive. I am, my age I suppose, confused about the wiring as far as the white/blue wires go. I have installed an 0402 LED into the headlight and am ready to wire it into the decoder. Here is what I think I understand: 1. blue wire is common (+) and the white is for the headlight 2. since the decoder output tested out to be 14.4v I will use a resistor 3. I have made a small PCB with a 1.8K resistor on it I have tested this set up and it works well on the bench with a little dimmer light than most steamers have in them from factory. I am happy with the result. I have programmed rule 17 and it works well. I used a 3.2 forward v LED with magnet wires. I tested the LED with a 3v coin batt by attaching red wire to (+) side of the batt and it works. So should I attach the decoder blue wire to the LED red wire ? This would be the decoder (+) wire to the LED anode lead. Now, does it matter which wire (blue/white) that I apply the resistor? ? ? I have not questioned myself, in the past, like this. Appreciate any feedback. Stay well, Carl
I would think the resistor could be on either end of the circuit but I run the blue to the resistor. Then to the anode side of the LED. Then the white, if it is front light to the cathode side of the LED or the yellow if it is the rear light. I only run the front or rear at a time never at the same time so use the one resistor for both a lot of times. Blue wire to resistor. Other side of resistor to nearby light. Another wire from that side back or forward to the other LED with either the yellow or white to the decoder. Above is one example of using one resistor for both lights if they aren't on at the same time. The PCB replaces a DC light board so also provides track power to the decoder. The blue wire from the decoder goes to the right side of the SMD resistor. Power after the resistor goes to the LED to the left of it and another wire (blue in this case but use what you have) goes to the other end of the loco and the led there with either the white or yellow attached to the other side of the LED. You could use one of your wired LED's and connect the red magnet wire to the side after the resistor and the other LED wire to either the white or yellow depending on which end of the loco it is on. Above you asked if you could connect the red magnet wire to the blue wire. Only if you first go through the resistor or you have the resistor on the other side of the LED. The resistor has to be in that circuit at some point or the LED will blow. Sumner
Thank you Sumner, a very nice complete discussion. Oh yes, I do know about resistors. I made a small PCB and attached a 1.8K resistor. Just the right amount of illumination and not overpowered as some r-t-r's have. Do you still have the cool p/up and do you still do Bonneville? ? Carl
Do you have any pictures of how/where you want to mount the small PCB you made? Is the LED on it or just the resistor. On the value I started with 1K resistors as that is enough to protect the LED but as you said they are really bright in most cases. Mainly using 1.5K now but in some cases they might also be too bright. I'm lazy and have a lot of these to do so don't experiment as much as I should loco by loco. I picked up some different fiber optic cable the other day in different diameters and might experiment using it in some cases. I could put the LED'S about anywhere and run the cable to either end vs. 2 or 3 wires. The .25mm (.010) is really small and should go about anywhere.. The fiber optic is really cheap. For about $12 I got a number of sizes and more than I'll ever probably use in this lifetime. Still have the pickup and not so cool anymore. I put 150,000 miles on it driving it all over the country and over a couple thousand on the salt at Bonneville which is worst than driving it in the ocean. Lots of rust on it now. Parked out front and it will be here for my wife to deal with after I'm not. Had it for 45 years now and build my first house using it to haul all the lumber and sand and gravel for the cement (at about 45 mph) as it was still stock and wore out. Bought it for $150. Too attached to it and too many memories to let it go. Last time at Bonneville was 4 years ago. We quit running Hooley's Stude then and the course has been pretty bad since. It is long hot days from 5 in the morning till 7 at night and just getting too old to do it. I have the lakester I started in the shop and hope to pass it on to someone else to eventually finish or at least use parts of. Covid has kind of put a halt on that happening. Lots of good memories from all the years we ran on the salt though. You ever been? Anyone that is a car guy needs to go at least once. Sumner
Sumner, Here is a picture of the board that I made as well as where it will go. It is a 1.8K resistor. I can mount it on top of the decoder or probably better on top of the lead weight. This next image is of the 0402 LED (3.2v) mounted inside of the headlight and for this picture it is powered by a 3v pancake batt.. I tested the circuit with the board attached and a 9v batt and the meter indicated 2.45v to the LED. Yes I am a car guy but have only driven by the salt flats while on vacation. Sort of funny, when I retired I could not decide if I wanted to "play trains" or have an older muscle car. I chose trains thinking it would be cheaper. Now after 28 years in N Scale I am not so sure about the economics. But I have fun! Thanks for your input, Carl PS: I have used fiber optics in my wife's Smokey Bear SD-40 snoot. I added headlight and ditch lights. These were straight line installs, not sure and have not tried any bending of the fibers. I have since cut down the cab light........
Wow there is a lot going on there. Those 403's are really, really small. I have some 603's and 1206's. Most of the time I can use the 1206 and it is easier to solder to. Same with the SMD resistors, only use the little ones when I have to. I found that I can use the PCB ties I make for turnouts when there is room for them. In the example above you could solder another wire right after the resistor and take it to another LED that isn't lit at the same time this one is. The whole works is thin enough that it can lay on top of the decoder if it is where one of the light boards was before the decoder install. I've been into cars, motorcycles, sail boats over the years and they can all be as expensive as you let them be. Enjoyed them all. Trains came along about 3rd in the sequence in the late '60's and left it in the 70's to pursue the other three over the years. I always knew I'd return so keep all my magazines and what train items I had from that time period (a little HO and N). Glad to be back and really enjoying it. You aren't too far from me in 'western distance terms'. If you plan on getting up this way, Utah canyon/mountain country, be sure and let me know. That is if things get back to somewhat normal at some point. Age wise we are pretty much staying to ourselves at the moment with COVID. Sumner
