# Installing a Decoder



## Tom Bray (Jan 20, 2009)

I have an NCE decoder that came with my NCE ProCab system that I am putting into an Eggliner.

The motor works fine although it is still a bit jumpy (I need to figure out how to clean the wheels, or something, on the truck since Aristocraft doesn't think that it needs to use separate shoes for power pickup).

Anyway, the decoder has something like 9 outputs and the Eggliner has a total of about 6 lights.

What I would like to do is have the rear facing marker lights run in the A / B strobe mode when moving forward and the front marker lights on solid. When going in reverse, I want to have the lights reversed also.

What I was thinking is to somehow connect multiple outputs together, probably through diodes, to allow the strobe to be active in one direction and the lights on solid when running in the other.

Has anyone done this? Since I don't have a schematic of the controller, I can't just look at it and determine if this would damage anything. I can't imagine that it would be a problem but then, I didn't design it.

Tom


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## Greg Elmassian (Jan 3, 2008)

You might start by telling us the model of the NCE decoder... I'm guessing a D408, but there are a couple of versions of the 408. 

You were saying you "don't have a schematic of the controller", do you mead the decoder or the existing wiring in the eggliner? 

The NCE manuals are available online. 

They have a great forum also. 

Regards, Greg


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## George Schreyer (Jan 16, 2009)

The NCE decoders have a rich lighting feature set so that the decoder itself MAY be able to do all of what you want. You need to read the documentation for your decoder to determine how to configure it. As far as the lighting goes, it will be easy because you indicated that there are more function outputs than lights. You need to wire the headlights to the functions specifically assigned to that task and each other light to a single function. Then you will be able to assign attributes to those functions to do the strobe function AND to make them direction sensitive.


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## Tom Bray (Jan 20, 2009)

I think it is the D408-SR version (I am not at home so I can't just look at it). I have had the system for a little over a month and the decoder was included in the kit. I have noticed that the manual isn't particularly specific as to exactly what it will accept for input and its total drive capability, and all that stuff. 

The NCE website manual for the D408-SR is the same as what I have except the price on the website is $89 where mine says $69. I didn't notice any other differences.

The wiring on the eggliner is pretty straight forward, power, motor, 6 lamps in parallel. I just don't know what the outputs look like coming off of the decoder and how it is powered to determine if I can just hook two outputs together using a pair of diodes into one lamp. 

The decoder has 9 outputs total, one is just an output, the rest all seem to have the special effects. There is a bit to turn on the effects in forward and or reverse plus the ability to assign the output to support an LED. 

I was going to use the basic output for interior lights, 6 outputs (combined) to do the side marker lights, and 2 for the fore and aft headlights. 

4 of the side marker lights would be set to strobe A/B and then two would be assigned to be on in either forward or reverse direction travel. These 6 outputs would be combined using diode "or" circuit to allow the forward direction markers to be on solid and the reverse ones to be flashing in a wig wag fashion (strobe A and B). My other thought was to pull the 4 marker lamps and put a white LED and a red LED in each spot so the ones going backwards were red. 

This thing is pretty much supposed to be a fun little car so the more effects the better. I am also considering using it to drive the movie camera around the layout - I am hoping that the DCC will smooth out its operation.


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## Tom Bray (Jan 20, 2009)

According the manual the outputs can do a single effect and be set for either forward or reverse. It doesn't appear that I can have a separate effect in forward and another in reverse.


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## Greg Elmassian (Jan 3, 2008)

The 408-sr is not a BEMF decoder. As much as they say "don't use BEMF to try to improve a poor running loco", you might want to consider a BEMF decoder if you have slow running problems. 

But, historically, that is a proven motor block, so you may have either dirty wheels, or an internal wiring problem, check that all 4 wheels pick up power. 

Regards, Greg


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## Tom Bray (Jan 20, 2009)

I probably need to take the motor block apart and check it out (I don't really want to do that right now but maybe I need to). I measured the resistance last night and I was not particularly impressed with value - it wasn't zero ohms. I was using an analog Simpson meter so I don't remember the actual value, it was on the x1 scale and I had checked the zero setting. 

The Eggliner only has about 5 hours of run time on it. It may have been sitting on a shelf for a while prior to me getting it, though. It came from Lantz's and I would imagine that they move stuff through there fairly quickly.


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## Greg Elmassian (Jan 3, 2008)

I don't have an eggliner, but believe the motor block is like the FA/RDC/RS-3 

If so, there are a number of failure points in power pickup. 

One part is where the long thin wire goes from the internal connections to the recess and presses against the outer ball bearing race on the "fixed" axle. 

(someone confirm my assumption of the type of motor block?) 

Regards, Greg


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## George Schreyer (Jan 16, 2009)

Each load is powered from the "blue" wire which has rectified track voltage on it. Each function output is a switch to the internal decoder ground. Each load is wired from the blue wire to a function wire, it needs to be set up to handle track voltage. 

The NCE decoder does have the ability to modify function outputs depending on direction, it just cannot assign different FWD and REV attributes to a single wire 

There is a way to do it though. The programming for that decoder lets you select an attribute from FWD, REV, neither or both. You can use TWO function outputs for one lamp by wiring the lamp to BOTH functions and then setting the attributes for one function to FWD and the other function to REV. Since you will probably be using both forward markers together, wire them in parallel. Be careful that the total load of two bulbs does not exceed the load capability of a single function wire. Do the same for the reverse markers. Combined with the headlights, this will consume six total functions. You use function remapping to assign the function wires to the throttle buttons that you want. You can map several wires to a single button.


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## George Schreyer (Jan 16, 2009)

BTW, don't take it apart unless you find something broken. Set the Eggliner on the track and alternately lift each end so that only two wheels remain on the track. If it works from both ends, there is no need to disassemble it. You may need to clean the wheels or the track.


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## Tom Bray (Jan 20, 2009)

I played around with the decoder last night and it just didn't seem to work right. Then I figured out that the conversion between the CVs that control the output signals and the actual wires were off by one. When I added 1 to the values in the manual things started to work. I haven't figured out exactly what is going on because the first output wire works as advertised. The manual indicates that it is for version 3.5 of the decoder, I have 3.6 (or 36) when I read back the decoder information. 

I also determined that the lamps in the Eggliner draw 75ma each at 22.5V which means I can't combine two of them into one output (100ma max per output). I am going to change them to LEDs. They do come out of their mountings pretty easily after they have been on for a minute or two so that isn't a problem. 

I am going to go see what the selection of LEDs is at Radio Shack tonight before I order something off the internet. 

Tom


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## George Schreyer (Jan 16, 2009)

theLEDLight.com sells good ones 6/$6. 

also look at superbrightLEDs.com 

RS ones are too expensive


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## George Schreyer (Jan 16, 2009)

also, do you have DecoderPro? If you are going to do much decoder programming, this free software can help but you might have to spend some money to connect your computer to your DCC system. 

http://jmri.sourceforge.net/


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## George Schreyer (Jan 16, 2009)

The LEDs might be too directional until you make a mod to the marker lamp housing, see 

http://www.girr.org/girr/tips/tips3/streamliner_tips.html#lighting


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## George Schreyer (Jan 16, 2009)

about the lights, you might get enough brightness with a resistor in series to limit the current to each bulb to 50 mA at your voltage. 22.5 volts sounds high unless your track voltage is really 24 volts. The actual voltage on the bulbs will be about 2 volts less than the DCC track voltage as measured with a scope or true RMS voltmeter.


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## Tom Bray (Jan 20, 2009)

Well, I found "super bright" white LEDs at one of the Radio Shacks, they have 7000mcd and a viewing angle of 30degrees, approximately 0.2" in diameter. They fit perfectly into the plastic light fixtures and look pretty good, at least in the room - I will have to see what they look like in daylight. The case is clear and I did read that that was supposed to be less than optimal but it appears the lamps do a pretty good job of directing the light. 

Radio Shack had some that had a higher viewing area but had a lot less light output and they over $5 each ... decided the pair for $1.80 was a better place to start. If I decide I don't like them I can easily replace them with something else. 

The decoder has a setting for most of its outputs for and LED with a 1K resistor in series, I just have to make sure I don't unset that bit. That seems to work pretty well. 

I ended up wiring the lights so that the default headlight outputs also have a pair of diodes that allowed turning on both marker lights in the same direction. The marker lights also have their own separate output which is currently set for the strobe A & B outputs so they flash alternately. It looks pretty good. 

The big problem was figuring out which outputs worked where. The documentation says the the yellow wire is for rear headlight and is addressed as output 7, it is really output 2. The output on the yellow wire is green/white. It turns out that the forward and reverse direction registers wouldn't address that output, at least using their "default" mapping. The output worked fine if turned on using function keys 4, 5, or 6 but 0 through 3 wouldn't control it - I ended up replacing that output with a different one. 

It isn't finished but all the lights work and it goes in the correct direction. The lights follow the direction of travel and I got the shell to be facing forward. I still have to glue the LEDs into the holders, dress the wires and decide how to do the interior lights and in general clean up the interior. 

My biggest beef is that the documentation said one thing, the decoder behaved differently, and there were little land mines sprinkled around to trip you up. 

Are all decoders this way? There was some note in the documentation that the NMRA standard allows some limitations as to which outputs were addressable from which functions but it didn't elaborate beyond that and the table that was provided. Also all the documentation said the the reverse head light was addressable as bit (decimal) 64 when in reality it was bit 2. Even the control register for the light effects was set to the second register, moving all the other outputs up by one. It was pretty late when I got it working, reminded me of the days of fighting with computers until wee hours of the morning. Anymore I can only do that on a Friday night. 

Tom


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## Tom Bray (Jan 20, 2009)

Posted By Tom Bray on 10 Apr 2010 09:05 AM 
Well, I found "super bright" white LEDs at one of the Radio Shacks, they have 7000mcd and a viewing angle of 30degrees, approximately 0.2" in diameter. They fit perfectly into the plastic light fixtures and look pretty good, at least in the room - I will have to see what they look like in daylight. The case is clear and I did read that a clear case was supposed to be less than optimal but it appears the lamp housings do a pretty good job of directing the light. 

Radio Shack had some that had a wider viewing area white LEDs but had a lot less light output and they cost over $5 each ... decided the pair for $1.80 was a better place to start. If I decide I don't like them I can easily replace them with something else. 

The decoder has a setting for most of its outputs for and LED with a 1K resistor in series, I just have to make sure I don't unset that bit. That seems to work pretty well. 

I ended up wiring the lights so that the default headlight outputs also have a pair of diodes that allowed turning on both marker lights in the same direction. The marker lights also have their own separate output which is currently set for the strobe A & B outputs so they flash alternately. It looks pretty good. 

The big problem was figuring out which outputs worked where. The documentation says the the yellow wire is for rear headlight and is addressed as output 7, it is really output 2. Output #7 that is supposed to be the yellow wire is really green/white (in position 6 on the connector). It also turns out that the forward and reverse direction registers wouldn't address that output, at least using their "default" mapping. The output worked fine if turned on using function keys 4, 5, or 6 but functions 0 through 3 wouldn't control it - I ended up replacing that output with a different one (#5, a brown wire). 

It isn't finished but all the lights work and it goes in the correct direction. The lights follow the direction of travel and I got the shell to be facing forward. I still have to glue the LEDs into the holders, dress the wires and decide how to do the interior lights and in general clean up the interior. 

My biggest beef is that the documentation said one thing, the decoder behaved differently, and there were little land mines sprinkled around to trip you up. 

Are all decoders this way? There was some note in the documentation that the NMRA standard allows some limitations as to which outputs were addressable from which functions but it didn't elaborate beyond that and the table that was provided. Also all the documentation said the the reverse head light was addressable as bit (decimal) 64 when in reality it was bit 2. Even the control register for the light effects was set to the second register, moving all the other outputs up by one. It was pretty late when I got it working, reminded me of the days of fighting with computers until wee hours of the morning. Anymore I can only do that on a Friday night. 

Tom


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## Tom Bray (Jan 20, 2009)

Looks like edit posted my reply twice ... grr


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## George Schreyer (Jan 16, 2009)

NCE decoders are more cryptic that most about what wires are which. On some of them, most or all of the function wires are brown and you have to count them across the connector. 

All is not sweetness and light with other brands either. The DG583S reverses the sense of the white and yellow wires from the "standards" and their own documentation. 

The wider angle LEDs put out exactly as much total light as the narrow angle ones all other things being equal. The intensity is rated at the peak of the pattern so that one with a narrow pattern is more intense in THAT direction, but they cover other directions more poorly. 

- gws


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## Tom Bray (Jan 20, 2009)

The LEDs wash out in direct sunlight, at least the side markers do. You can tell the headlight is on, which is probably all that matters. Once evening arrives, it looks fine, pretty much matches all the lights on the rest of the layout. I am not happy with the flashing pattern of the lights, you can't tell what it is doing unless you are directly behind it, so I need to change that. 

One thing that I am not thrilled with is that it no longer draws enough current for the auto reverser to detect that it has run onto the end rails reliably. I need to work on the DCC automation so that I can remove the DC controls - also every time the eggliner jumps the track it takes out the fuse. It seems to have trouble with the frog on one of the Aristo wide switches (plastic frog). 

The eggliner also doesn't like pollen on the rails - gummed up the wheels and it wouldn't run.


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## Greg Elmassian (Jan 3, 2008)

Tom, what does "run onto the end rails" mean? Is that a derailment? 

Check your back to back gauge on your eggliner, and maybe shim your guardrail on the switch to NMRA/G1MRA standards, it's WAY too wide from Aristo. 

Regards, Greg


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## Tom Bray (Jan 20, 2009)

I have an auto reverser and the end rails are two diode isolated rail sections, the reverser sees that there is no longer a train on the track, counts down and reverses the polarity (this is DC, not DCC based). What is happening is that there appears to be enough leakage in the circuit that the reverser doesn't see that the Eggliner is sitting at either end. I was playing with my NCE control panel and I now have a DCC based version of the auto reverser - all I have to do now is install it on the layout. 

I was playing with the switches, actually 2 of them were causing the Eggliner to derail. It appears that the flanges on the Eggliner wheels are a bit larger than my other pieces of rolling stock. The frog on the switches were launching the Eggliner up in the air and derailing it. I used a Dremel with a small grinder cut the frogs a bit deeper, the problem with derailing went away, the Eggliner doesn't jump around as much when it goes through the switch now too. 

I am also finding that I have to clean the wheels on the Eggliner a lot, otherwise it won't run smoothly. I wiped down all the rails (I didn't realize how much track I have down), cleaned the wheels, and after a little while it started running erratic again. I cleaned the wheels a second time and then it ran OK for the rest of the evening. 

Tom


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## Trains West (Oct 4, 2008)

maybe a lenz decoder would be better for this as it has built in back and forth operation and if you add a power 3 it has on board energy so it is less fussy about power pickup


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## Tom Bray (Jan 20, 2009)

Yes, something like the Lenz decoder would probably be better but I think I have done enough to this poor little Eggliner already. 

One of my goals was to do a practice run before I took on my New Orleans Trolley with a new decoder and sound module. That one needs to be done more carefully and I don't have as much margin for error on that one. It is also going to be more complex since I have to figure out how to put a speaker into it.


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## Trains West (Oct 4, 2008)

I just mounted the speaker with a cup around it in the body and let it sound through the body shell did just fine


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