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DCC decoder in a OMI locomotive

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Posted by fondo on Monday, March 7, 2011 11:50 AM

Randy, thanks for all your support. Yes, the blue common is the positivie(+) in the led. I have just received the answer from digitrax suppot, and the solution is the following: I use led with 660 resistor. The two led are draw by me as circle with an X, something like this (X)

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  • From: Reading, PA
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Posted by rrinker on Monday, March 7, 2011 11:45 AM

 LEDs are polarity senstive - the blue wire is + on the decoder, so make sure you have the LED hooked up the right way. A valid 'blue' wire point would be one side of either the front or rear LEDs that are soldered to the board. I'm not so certain the green wire coming from that 9 pin connectors is THE green wire like you'd see on a regular wired decoder. The second connector (or in this case only one) on other Digitrax sound decoders provides the connection for the speaker the capacitor, and the chuff cam (yes, even the diesel decoder has a chuff cam connection, because you can use that decoder in a steam loco and load the appropriate sounds).

                 --Randy

 


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

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Posted by fondo on Monday, March 7, 2011 8:16 AM

Thanks Randy, what I did was to search for continuity with a voltimeter with the two led's installed, and I founded the leg that should be blue cable. So I use it for one leg for one ditch light(another led, with 990ohm resistor) and the green cable to the other leg of the ditch light, CV51 with 106 value, and CV52 with 107 value, CV63 with 64 value but this didn't work. I sent an email to digitrax support already, so when I get news I'll post them here!

THanks for all your time! and quick responses

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Posted by rrinker on Monday, March 7, 2011 1:22 AM

 Looks like you've hit a serious omission from the manual for this decoder - where the heck are the pads for the extra functions? The wires coming from the 9 pin plug, with 2 already connected to teh speaker adn 2 already connected to the capacitor, are NOT the function wires or the normal hookup for power or the motor, because this is a replacement board for the standard Kato light board. Usually on such decoders there are pads to solder wires to for the extra functions, and one is the equivalent of the blue common wire. But the manual for this one does not show that, nor do any of the similar ones (there are versions for the SD38-2 and F40PH as well - same board but slightly different size to fit the other locos). I did some searching and did not find where this is mentioned anywhere. You may have to call or email DIgitrax about this.

                     --Randy

 


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

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Posted by fondo on Sunday, March 6, 2011 9:14 PM

Great, I've one problem. I removed the shell of the AC4400, and I'm watching the cables and I don't have the blue as shown in the image for common's cable of the lamps, just red, white, brown, violet, green, and yellow. The blue one goes to the capacitor, and also the black one.

Which would be the two cable for each lamp of ditch lights?

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Posted by rrinker on Sunday, March 6, 2011 8:48 PM

 The settings listed int eh PDF will make the ditch lights flash when you press F2 - which corresponds to the horn, so if you're using the sound decoder, when you blow the horn the ditch lights will start flashing - exactly as they should. The nitty-gritty is that there is a 'phase a' and 'phase b' for the lighting effects, when A is on, B is off, and vice-versa. So what those settings do is set it so that one ditch light, on the green wire, is phase A, and the other ditch light on the purple wire is on phase B. Labeling the wire colors as a specific function is only a default - another of those CV settings make both the green and purple wires activate when you press F2. Depending on the decoder, you can change which F button turns on which wire in almost any combination you want.

                --Randy

 


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

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Posted by fondo on Sunday, March 6, 2011 8:28 PM

Ok, I've just understood how to change the values of the CV's, but what value should I set for F1 / F2 (Functions) for dicht lights flash alternately? and how can I set to press F12(not used, or another F#) to start flashing? (sorry if this are questions are totally from a newbie, but that's what I'm hehe)

 

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Posted by rrinker on Sunday, March 6, 2011 5:46 PM

 What CVs to program depend on the decoder.

If you use the green and violet with a Digitrax decoder, the CVs are listed in the PDF document. Use the decimal numbers, only ancient Digitrax systems needed hex numbers.

for ditch lights you will either need some micro bulbs to fit, these are usually 1.5 volts and will need a resistor on each one to reduce the voltage. Or use surface mount LEDs. These also need a resistor. You cna buy them with wires already attached since it does take some practice to solder wires to somethign that tiny.  Third option is fiber optics int he actual ditch light castings with bulbs or LEDs inside the body. I recomment LEDs for all lights, they run cool and theoretically will never ever burn out. You'd want a 1K resistor to use with each LED, maybe somethign larger like 2.2K for the ditch lights if they are too bright.

                      --Randy

 


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

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Posted by fondo on Sunday, March 6, 2011 4:57 PM

I founded this image for wiring the decoder. And this PDF
Also, I've some difficult to understand how to program with my NCE Power Cab the Functions 1 and 2 to make ditch lights flash alternately, any help on this?

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Posted by fondo on Sunday, March 6, 2011 2:19 PM

Randy, thanks for you answer! To flash alternately the ditchligths I will have to use the cables that come? if yes, how do I know which one, and what lamp's voltage should I use?

What brand would you recomend me decoder with sound for the AC4400?? I will try to search for videos but I think they are depending on the video's camera quality.

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Posted by rrinker on Sunday, March 6, 2011 11:03 AM

 That decoder has 6 functions, so yes, there are enough to run ditch lights, but the sounds are less than satisfying and some have had operational issues with them, like the loco slowing down when you blow the horn. If you are happy witht he way it sounds, there definitely are enough function connections to do what you want.

 Not sure what brands you may have readily available there, but in addition to the Digitrax and TCS ones, NCE has the D15SRJ which has enough functions for the ditch lights, and you can probably get Lenz fairly easily. The Silver+ decoders have 5 functions, the Gold Series have 4, so those would work.

                        --Randy

 


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

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Posted by fondo on Sunday, March 6, 2011 8:34 AM

Thanks to all for posting, I'm still yet searching for a 6 functions decoder in my country without luck. Yesterday I got my NCE Power Cab and tested with emotion Big Smile

One of the decoders I got was the Digitrax with Sound for Kato AC4400, I think it could be a bit more noise but I'm completely satisfied anyway. The model is SDH164K14
I was thinking if this decoder+sound can have the function for ditchlight to flash alternately? as I see that there are alone cables and maybe I could add two more lamps? If this can works and think this can be a great decoder to add to my Overland locomotive, what do you think? Is this possible?

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Posted by rrinker on Friday, March 4, 2011 11:11 AM

 If you plan to add the sound later, the best way to do this is probably install a ecoder that has the 9 pin plug on it. You can then later simply unplug the motor decoder and plug in one that does sound and motor - the best sound decoders currently are ones that do both so it's a bit of a waster to use two seperate decoders.

 The TCS T4X has 4 functions, enough for front and rear lights, plus the ditch lights. The T6X is 6 function, in case you also need a rooftop beacon. Later on, you can disconnect the 9 pin plug and plug in a Tsunami (and find a place to put the speaker) and you will now have sound.

                        --Randy

 


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

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Posted by richg1998 on Thursday, March 3, 2011 8:52 AM

In case you do not have the sites, below are the NCE site and TCS site links. Usually all the specs are shown.

http://www.ncedcc.com/

http://www.tcsdcc.com/public_html/index.php

Again, the Litchfield site will show many different types of decoders with specs even if you do not order from them.

Rich

If you ever fall over in public, pick yourself up and say “sorry it’s been a while since I inhabited a body.” And just walk away.

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Posted by fondo on Thursday, March 3, 2011 7:31 AM

Thanks rrinker, but if I want first a decoder just for locomotive fuction which one can be that later I can add sound? or it's better to leave that decoder for another loco and buy sound+decoder together?

Also my shop here, doesn't have the DH165D, just the IP one. Does NCE, TCS have a similar decoder?

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Posted by richg1998 on Thursday, March 3, 2011 7:30 AM

fondo

Thanks Hergy, richg1998, rrinker, Paul3 for yours replies!

So I will try to get the correct decoder as YES I want ditch light working WITH flash alternately, and what I forgot to say, is which decoder can do this? (DH165d?) and also can have the option to include sound in the future??

I've seen that Digitrax has a sound decoder for AC4400 but for Kato, would you recommend me this sound or better from another brand?(here in Argentina is not so simple to get all brands)

THanks again for your replies...

I would contact Litchfield Station for decoders. I do know some in the UK and the EU have bought from this company and they do answer email. Let them know where you live. There are different form factors for decoders. Litchfield pretty much spells out everything.

http://www.litchfieldstation.com/DCC-University/index.htm

Decoder mounting might be different depending on which decoder you are able to purchase.

If you had to build a shelf for say a light board type decoder, there are many different sizes of styrene.

Some decoders come with 12 volt light connections for bulbs and LED's and 1.5 volt connections for 1.5 volt bulbs on the same decoder. As was said, a resistor for the LED. One decoder includes LED connections with the resistors on the decoder.

I use a double sided tape from Litchfield that works very nice and can still remove the decoder if there is a problem.

There are some different ways to do this. Post some photos when the project is done.

RIch

If you ever fall over in public, pick yourself up and say “sorry it’s been a while since I inhabited a body.” And just walk away.

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Posted by rrinker on Thursday, March 3, 2011 7:26 AM

 If you want a better sound option, Soundtraxx has a Tsunami with the appropriate sounds for the AC4400 and QSI also has one with the proper sounds. Either one will be better overall to the currently available sound files for the DIgitrax decoders. Both are motor plus sound, so it's the only decoder you need. ANd they both have enough function outputs to provide the ditch lights - and if you want they will even work with the horn, so when you blow the horn the ditch lights will start flashing, and kep alternating for a set time afterwards, when they will revert to both just being on - this is how they operate in my part of the US anyway.

                         --Randy

 


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

  • Member since
    November 2009
  • 113 posts
Posted by fondo on Thursday, March 3, 2011 6:51 AM

Thanks Hergy, richg1998, rrinker, Paul3 for yours replies!

So I will try to get the correct decoder as YES I want ditch light working WITH flash alternately, and what I forgot to say, is which decoder can do this? (DH165d?) and also can have the option to include sound in the future??

I've seen that Digitrax has a sound decoder for AC4400 but for Kato, would you recommend me this sound or better from another brand?(here in Argentina is not so simple to get all brands)

THanks again for your replies...

  • Member since
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  • From: Massachusetts
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Posted by Paul3 on Wednesday, March 2, 2011 9:45 PM

fondo,
If you read my post, that's exactly what I suggested.  You really should make sure the engine runs properly before tackling the lighting.  Once the engine runs, the lighting can be done later or not at all.  Your choice.  But you need the motor done first.  As for which resistor, I usually use a 680 ohm as I said above.

Hamltnblue,
Please don't confuse the guy.  For one thing, the motor itself does not have to be isolated from the frame, only the motor brushes (or contacts) have to be isolated.  Secondly, it's an Overland.  I've yet to see any Overland where the brushes are not isolated, and I've installed DCC in perhaps a couple dozen OMI's.  So fondo, don't worry about it with this engine.

richg1998,
This decoder mount is not structural.  He doesn't need to fabricate a big styrene shelf.  A simple piece of Magic Tape holding the decoder to the top of the motor will work fine as long as the wires don't drag on a flywheel.

If anyone is really concerned, there's a little trick one can do with these OMI's.  The PCB the diodes were on that came with the model makes a great shelf for the decoder.  Strip off all the components that are on the PCB with nippers.  Tape the decoder to the PCB, then screw it on to the shelf bracket.  Viola!  Instant mounting for the DCC decoder.

Paul A. Cutler III

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Posted by rrinker on Wednesday, March 2, 2011 9:28 PM

 Of the two decoders you mentioned, the DH121D would work, but not if you want ditch lights along witht he headlights. You'll need a better option - the DH165IP is a decoder designed to plug in to an 8 pin socket, you need to hard wire this one. A suitable DIgitrax decoder that has enough functions to do the ditch lights and all is the DH163D. The TCS T4X would also work - unless you have a rooftop beacon as well at the ditch lights and headlights, in which case you'd need the T6X.

 Bottom line, you need a wired decoder that has enough functions to handle all your lights you wnat to include. Front and rear lights are two functions, ditch lights need another 2 if you want them to flash alternately, and then a rooftop flasher or whatever would be another. Too many choices to list them all.

                  --Randy

 


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

  • Member since
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  • From: Western, MA
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Posted by richg1998 on Wednesday, March 2, 2011 5:15 PM

Hergy

Based on your questions I think your first step should be to buy the Kalmbach book on DCC and study it. Hardwiring a decoder into a brass loco for your first try is a big and potentially difficult job for your first. The info you have been given thus far, while accurate and probably helpful, I feel may be a bit over your head. Just my perception. Good Luck.

From what I can see, mounting the decoder securely will be a bit of a challenge. No doubt have to make a support shelf over the drive shaft to mount the decoder. I have done something like that in a Spectrum 70 ton but I was able to put  styrene shelf in place for the decoder and a small piece of copper clad PC board to minimize wire splices. I have some Vero board from the UK I picked up some years ago for various electronic projects.

I then followed the instructions that came with the decoder. Many sue 1 k resistors but a few use maybe 2k for ditch lights as they thought with 1k, the lights were too bright but it is your railroad.

Below is what I did for my loco as an idea. I have used this PC board in other loco conversions.

Rich

If you ever fall over in public, pick yourself up and say “sorry it’s been a while since I inhabited a body.” And just walk away.

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Posted by Hergy on Wednesday, March 2, 2011 4:54 PM

Based on your questions I think your first step should be to buy the Kalmbach book on DCC and study it. Hardwiring a decoder into a brass loco for your first try is a big and potentially difficult job for your first. The info you have been given thus far, while accurate and probably helpful, I feel may be a bit over your head. Just my perception. Good Luck.

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Posted by richg1998 on Wednesday, March 2, 2011 3:48 PM

fondo

How do I check the isolation? I cannot take a piece from the other side because the cable length doesn't allow to turn it

 

Use the ohms scale of your multimeter. Trying to do this at this level without a meter will be difficult for those who do not understand electrical.

There should be no electrical path between the frame and either motor contact. I use Kapton tape from Litchfield Station. This is a tough thin tape. Make sure you cannot see any wire from each motor contact touching the frame anywhere.

Below are some useful links about DCC. Take time to read though then as it will enhance your knowledge of DCC.

http://www.mrdccu.com/

http://www.members.optusnet.com.au/nswmn2/DCC.htm

While this will not exactly answer all your questions for this particular loco, you will have a lot fo useful DCC info for the future. There are basic NMRA wire codes for DCC and the info is in those links.

Rich

 

If you ever fall over in public, pick yourself up and say “sorry it’s been a while since I inhabited a body.” And just walk away.

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Posted by fondo on Wednesday, March 2, 2011 3:29 PM

how do I check the insolation? I can not take a pice from the other side beceause the cable length doesn't allow to turn it

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Posted by Hamltnblue on Wednesday, March 2, 2011 3:28 PM

Take a pic of the other side of that circuit board there.

Also check to make sure that the motor is electrically isolated from the chassis. If it isn't you'll have to insulate it with electric tape.

Springfield PA

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Posted by fondo on Wednesday, March 2, 2011 3:22 PM

Thanks for showing the picture!

Do you think that in can be a start point trying to make work the decoder just for moving the loco and then try with the light?
Also which resistor should I use?

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Posted by richg1998 on Wednesday, March 2, 2011 3:17 PM

Hamltnblue

his third pic:

http://postimage.org/image/1x4bthe10/

 

http://postimage.org/image/1x4bthe10/

Rich

If you ever fall over in public, pick yourself up and say “sorry it’s been a while since I inhabited a body.” And just walk away.

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Posted by Hamltnblue on Wednesday, March 2, 2011 2:50 PM

his third pic:

http://postimage.org/image/1x4bthe10/

 

Springfield PA

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Posted by Hamltnblue on Wednesday, March 2, 2011 2:48 PM

fondo

Hello everyone, I'm doing my first steps in DCC and I would like to turn my OMI locomotive in DCC. I don't know how to do it, that's why I need you help on the procedure. I've taken photos and I do understand about electricity and using a tester. It would be greatful any comment you can give me or any web page where it explain how to do it.

It's HO scale, and I have the following decoders(if non of the are usefull, please tell me which one can be)

DH121D
DH165IP

Photos

https://lh6.googleusercontent.com/_UsOfXqoxLKo/TW5MrSgK7AI/AAAAAAAAAFY/uNqPz4G6Qaw/s720/IMG_7212.jpg


https://lh4.googleusercontent.com/_UsOfXqoxLKo/TW5MsD7NhPI/AAAAAAAAAFE/kET4XbYAqwI/s720/IMG_7213.jpg


http://s1.postimage.org/g3k2opp5m/IMG_7215.jpg


Thanks in advance! :D

Springfield PA

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